UNIVERSITY 
 LIBRARY 
 
Cornell University Library 
 QP 376.C14 
 
 Relations of mind and brain, 
 
 3 1924 024 799 045 
 
The original of this book is in 
 the Cornell University Library. 
 
 There are no known copyright restrictions in 
 the United States on the use of the text. 
 
 http://www.archive.org/details/cu31924024799045 
 
THE RELATIONS 
 OF MIND AND BRAIN 
 
PRINTED BY T. AND A. CONSTABLE, PRINTERS TO 1IKR MAJESTY, 
 AT THE EDINBURGH UNIVERSITY PRESS. 
 
THE RELATIONS 
 
 OF 
 
 MIND AND BRAIN 
 
 BY 
 
 HENEY CALDEEWOOD, LL.D. 
 
 PROFESSOR OF MOKAL PHILOSOPHY, UNIVERSITY OF EDINBURGH 
 
 MACMILLAN & CO. 
 1879 
 
'E/jol /xh yap oi tpalverai, S &v xpWTbv ?f <r«4/*o, touto rfi airov apery foxy" 
 ayaffjji/ iroLeiv, dXXo tovvo.vtI<x> ^vxy cfyalK) T% avrijs apery aCipa irapixtw m ottv 
 re §t\TioTov. Plato, Eepub. iii. 403. 
 
PREFACE. 
 
 The object of the present work is to ascertain what 
 theory of mental life is warranted on strictly scientific 
 evidence. 
 
 The order followed is to consider, first, the latest 
 results of anatomical and physiological research as to 
 the structure and functions of the brain ; second, the 
 facts in human life unaccounted for by anatomical and 
 physiological science, and requiring to be assigned 
 to a higher nature. 
 
 On the side of Mental Philosophy, it must be 
 recognised that analysis of consciousness cannot be 
 regarded as affording a complete survey of the facts of 
 personal life. On the other hand, it is clear that 
 the known facts connected with cerebral action do 
 not include familiar phases of mental activity. If 
 we allow ourselves to be engrossed with Physio- 
 
vi PREFACE. 
 
 logical investigations as to brain, we restrict our 
 attention to a single class of facts, and become unable 
 to take a view of human life as a totality. The 
 whole ran<re of evidence must be traversed, if we are 
 to secure a harmonious representation of the consti- 
 tution of human nature. 
 
 The acknowledgments I have to make for friendly 
 assistance during the long-continued and difficult 
 investigations involved are many. Great generosity 
 on the part of my colleagues has given me full 
 advantage of the facilities for inquiry which the 
 University affords. I have to record my special grati- 
 tude to Professor Turner, of the Chair of Anatomy, 
 who has been untiring in his friendly assistance ; to 
 * Professor Rutherford, of the Chair of Physiology ; to 
 Professor Crum Brown, of the Chair of Chemistry; 
 to Professor Grainger Stewart, of the Chair of Prac- 
 tice of Medicine ; and to Dr. Clouston, Lecturer on 
 Mental Diseases in the University. 
 
 I have also to express my particular thanks to Dr. 
 James A. Sidey for revision of the proof-sheets, and 
 to the Rev. Alexander Mair, D.D., for revision of 
 selected portions of the work. Valuable aid has also 
 been afforded me by Dr. Dodds, Assistant to the 
 Professor of Physiology ; and by Mr. Stirling, Assistant 
 
PREFACE. vii 
 
 to the Professor of Anatomy, and Assistant Curator 
 of the Anatomical Museum. 
 
 Readers will understand that no one of the 
 friends named is in the least degree committed to the 
 positions here maintained. 
 
 Thanks are also due to many authors and friends 
 who have kindly replied to inquiries addressed to 
 them. 
 
 Large tise of Illustrations prepared for standard 
 works in Anatomy and Physiology has been gener- 
 ously afforded me. Acknowledgment of these favours 
 is made as the illustrations are introduced. 
 
 H. C. 
 
 University of Edinburgh, 
 2Gth April 1879. 
 
CONTENTS. 
 
 CHAPTER I. 
 
 RELATIONS OF PHILOSOPHY AND SCIENCE. 
 
 PAGE 
 
 Physical Science and Mental Philosophy constitute a unity — The 
 problem of Existence is one, and must be interpreted by reference 
 to the nature of man as rational — Physiology and Psychology 
 constitute together the science of human life ; scientific methods 
 belong to both ; Psychology as truly as Physiology springs 
 from observation — Dependence on consciousness is not peculiar to 
 the mental philosopher — A charge of untrustworthiness cannot 
 be substantiated against self-consciousness — Experience of the 
 insane presents the only debatable points, yet the physician 
 trusts the consciousness of his patient — Introspection is a neces- 
 sary process for observation, but is not sufficient for a philosophy 
 of our nature — Physiology is not yet sufficiently advanced to 
 explain the action of nerve and brain — There remains as an 
 essential question, how to account for " mental phenomena," . 1-9 
 
 CHAPTER II. 
 
 STRUCTURE OF THE BRAIN. 
 
 Three membranes which afford covering for the brain ; appearance 
 of the brain ; its growth and increase in weight during early 
 life ; ordinary weight of European brain — Configuration and 
 structure of the brain — Side view of the organ ; convolutions ; 
 fissures ; subdivisions of the hemisphere-^Upper view of the 
 brain, showing distinction of the two hemispheres — Diversity of 
 convolutions in the two hemispheres — Basis of comparison of 
 different brains ; mass and weight ; quality ; proportion between 
 brain and body — Greater weight of brain in man than in woman 
 — Minimum weight of normal brain — Examples of heavy brain — 
 Internal structure of the brain ; the grey matter and the white ; 
 
CONTENTS. 
 
 nerve cells packed in neuroglia ; nerve fibres ; structure of fibre ; 
 chemical composition— Union of the hemispheres— Massing of 
 the sensory and motor nerves — Basal ganglia ; lower surface ; 
 subordinate parts of the nerve centre— Supply of blood for the 
 brain, .,.....•••• 10-38 
 
 CHAPTER III. 
 
 THE NERVE SYSTEM AS DEPENDENT ON THE GREAT NERVE CENTRE. 
 
 The nerve system ; nerves of special sense ; spinal marrow ; distribu- 
 tion of fibres ; efferent and afferent — The sympathetic system of 
 nerves — Sensory and motor nerves have their common meeting- 
 place in the brain — Stores of nerve energy, how acted upon ; 
 molecular changes consequent on activity — The grey matter not 
 sensitive under touch or injury — Facility of action of nerve 
 fibres acquired by frequent use — Relation established between 
 distinct nerve lines — Ratio of intensity in sensation — Nerves of 
 special sense ; smell ; sight ; hearing, 39-78 
 
 CHAPTER IV. 
 
 LOCALISATION OF FUNCTIONS IN DISTINCT PORTIONS OF THE BRAIN. 
 
 Inquiry as to the possibility of localising distinct functions in certain 
 parts of the brain — Electric excitation of the brain — Experiments 
 of Fritsch and Hitzig— Experiments of Dr. Ferrier, illustrated 
 by identification of sensory and motor centres in the brain of 
 the monkey— Analogous results with the brain of the dog- 
 Interpretation of the facts ; twofold classification of the centres ; 
 tests of accuracy; perplexity as to "silent portions," over 
 which excitation has proved impossible, . 79-122 
 
 CHAPTER V. 
 
 COMPARISON OF THE STRUCTURE AND FUNCTIONS OF BRAIN IN- 
 LOWER AND HIGHER FORMS OF ANIMAL LIFE. 
 
 Comparative structure of brain in different animals— Homoloev of 
 brain— Primary arrangement of nerve system— Brain of 
 frog, pigeon, rat, rabbit, cat, dog, horse, monkey, man-like° arP ' 
 man ; points of resemblance and difference between the t^' 
 last named — Brain of the elenhant and r.f +.*,«, ,.,i,_i. " i " " 
 
 «»<»« , jjun.i/o ui icoouiuiiiiiuc ana aiuerence betwet 
 last named — Brain of the elephant and of the whale 
 
 123-186 
 
CONTENTS. xi 
 
 CHAPTER VI. 
 
 RESULTS OF ANATOMICAL AND PHYSIOLOGICAL INVESTIGATIONS. 
 
 PAGE 
 
 Results of anatomical and physiological investigations — Common 
 characteristics of the nerve system, and of the nerve centre — 
 Increasing complexity of nerve system as we ascend the scale 
 of animal life — Distinction of sensory and motor apparatus in 
 all cases — Activity of sensory apparatus ; impulse ; relation 
 of peripheral organ to the nerve cell ;• action of corpuscle or 
 other terminal organ ; action of the correlated nerve cells ; con- 
 sequent experience — Motor apparatus ; impulse ; evolution of 
 nerve energy ; transmission ; consequent muscular activity ; 
 joint action of muscles — Ganglionic masses ; appearance of 
 brain ; union of hemispheres— The brains most complicated in 
 structure are associated with the most highly developed muscular 
 system — Evidence from electric stimulation — Regions in which 
 the superiority of the human brain appears, . ■ . 187-210 
 
 CHAPTEE VII. 
 
 PERSONAL EXPERIENCE AS CONNECTED WITH SENSATION. 
 
 Personal experience connected with sensation — Consciousness in 
 relation to brain activity — Touch and sensation — A series of 
 sensations ; distinction of sensations ; comparison of them — Per- 
 sonal experience as connected with these facts — Knowledge of 
 Self as distinct from sensations — Knowledge of the qualities of 
 objects by means of sensations — The voluntary element as it 
 appears connected with our sensations — Knowledge of a power 
 superior to sensibility of the nerve system — Mind not a series of 
 feelings — Conditions implied in the use of the special senses — 
 Sight and Hearing as examples, 211-236 
 
 CHAPTER VIII. 
 
 EXPERIENCE AS CONNECTED WITH MOTOR ACTIVITY. 
 
 Personal experience connected with motor activity — The sensory 
 nerve may be an excitor nerve, leading to reflex action — Distinct 
 from this is voluntary motor activity — Voluntary restraint over 
 
CONTENTS. 
 
 nerves of sensibility— Intelligent use of motor activity ; acquisi- 
 tion of skill in handicraft-Activity superior to the action and 
 reaction of nerve tissue— Reflection and personal determination 
 as connected with such activity— Knowledge of a power superior 
 to motor activity— Intelligent self-control— Impossibility of ac- 
 counting for the activity of such power by reference to the ^ 
 functions of brain, ... ... 237-261 
 
 CHAPTER IX. 
 
 RETENTIVENESS OF ACQUISITION — MEMORY. 
 
 Memory — Double aspect of retentiveness — Physical acquisition, re- 
 sulting in physical aptitudes — Memory proper as distinguished 
 from physical retentiveness — Difficulty and facility in retaining 
 knowledge — Both illustrate intellectual action as a phase of 
 voluntary control — Distinction and comparison involved in the 
 recollection of knowledge — Difference between retentiveness and 
 reproduction — Laws of association, the intellectual and the volun- 
 tary elements involved in their application — Theory suggesting 
 that the facts known are recorded in the tissue of the brain — 
 Its insufficiency to account for reproduction of knowledge, 262-284 
 
 CHAPTER X. 
 
 USE OF SPEECH. 
 
 Use of speech — The mechanism of speech — Physical acquisition in- 
 volved in use of speech — Articulate utterance is the expres- 
 sion of intelligent discrimination — Deaf-mutes, and the mode of 
 
 their education — Case of Laura Bridgman — "Lip-language" 
 
 Various phases of intellectual activity connected with the use of 
 speech— Aphasia, or loss of speech ; examples illustrating the 
 relation of voluntary intellectual action to speech, . . 285-312 
 
 CHAPTER XI. 
 
 ACTION AND REACTION OF BODY AND MIND. 
 
 Action and reaction of Body and Mind— Influence of a disturbed 
 bodily condition upon mind— Facts illustrative do not warrant 
 the inference that mental activity is an organic process Actio 
 
CONTENTS. xiii 
 
 PAGE 
 
 of Mind upon Body — Rational control over bodily movements ; 
 effect of deep emotion ; mental occupation modifying suffering ; 
 mind aiding recovery from disease ; personal determination as it 
 concerns endurance of toil or pain, ..... 313-325 
 
 CHAPTER XII. 
 
 WEARINESS, SLEEP, AND UNCONSCIOUSNESS. 
 
 Weariness attendant on mental effort — Difference between mental 
 work and brain work — The cause of weariness as the result of 
 intellectual work — Phenomena of sleep — Dreaming — Phases of 
 mental activity during sleep — Summary of conclusions as to 
 mental action during sleep — Unconsciousness — Physical causes 
 of it ; mental explanation of its occurrence — Somnambulism — 
 Trance— " Mesmeric Sleep," . . . 326-361 
 
 CHAPTER XIII. 
 
 BRAIN DISORDERS. 
 
 Brain Disorders ; misnamed " mental diseases " — Imperfect develop- 
 ment of brain — Disease of brain ; many forms of such disease ; 
 mental experience consequent upon it — Illustrations of dis- 
 ordered cerebral condition with accompanying mental experience 
 — Treatment of the insane, both physical and moral — Violent 
 injury to the healthy brain, and the light thrown on mental 
 activity by such injury — Personal conduct as producing or 
 averting insanity, . . . . 362-410 
 
 CHAPTER XIV. 
 
 THE HIGHER FORMS OF MENTAL ACTIVITY. 
 
 Higher forms of mental activity — Man regarded as a thinker — The 
 purely intellectual department of thought ; education ; scientific 
 inquiry ; recent advances in science — Thought as concerned 
 with the regulation of personal life — Moral law specially 
 applicable to human life ; the mode of its application — 
 Thought as concerned with the Absolute Being, and His 
 government of the universe — Religious beliefs existing among 
 uncivilised tribes — Philosophic speculation concerning the origin 
 of finite existence, 411-440 
 
xiv CONTENTS. 
 
 CHAPTER XV. 
 
 SUMMARY OF INTELLECTUAL RESULTS. 
 
 PACE 
 
 Summary of intellectual results — Personal experience as connected 
 with nerve sensibility ; and with motor activity — Voluntary 
 intellectual exercise illustrated in connection with the laws of 
 memory and the use of speech — Self-regulated life of man, as it 
 is manifested in the process of reflection or reasoning, in the 
 guidance of personal conduct under authority of moral law, and 
 in the religious beliefs and rites of the various races of men, 441-448 
 
LIST OF ILLUSTRATIONS. 
 
 Fio. 1. Outer Covering of Brain, . 
 „ 2. Position of Brain in the Cranium, . 
 „ 3. Right Hemisphere op Human Brain, 
 „ 4. Upper Surface, 
 
 „ 5. Outline of Convolutions, — Bight Side, 
 „ 6. „ „ Upper surface 
 
 ., 7. Section of the Grey Matter, 
 „ 8. Nerve Fibre, .... 
 „ 9. Union of the Hemispheres, . 
 „ 10. Appearance of lower portion of Brain, 
 „ 11. Basal Ganglia, 
 „ 12. Lower Surface of Brain, 
 „ 13. Lower Divisions of Nerve Centre, . 
 ,, 14. Section of the Spinal Cord, 
 „ 15. Touch Corpuscles (magnified), 
 „ 16. Structure of the Eyeball, . 
 „ 17. Structure of the Retina, 
 „ 18. Section of the Ear, . 
 „ 19. Internal arrangements of the Ear, 
 „ 20. The Labyrinth of the Ear, . 
 ,, 21. Upper. Surface of Brain of Dog, 
 ,, 22. Brain of Monkey, 
 
 „ 23. „ „ Centres of stimulation, 
 
 „ 24. Upper surface, „ ,, 
 
 ., 25, Brain of Dog, .... 
 „ 26. „ Carp, 
 
 „ 27. „ Frog, 
 „ 28. „ Pigeon, 
 
LIST OF ILLUSTRATIONS. 
 
 Big. 29. Brain or Eat, .... 
 
 „ 30. „ Babbit, .... 
 
 „ 31. „ Cat, 
 
 „ 32. „ Dog, .... 
 
 „ 33. Internal Structure of Dog's Brain, 
 
 „ 34. Brain of Horse, .... 
 
 „ 35. „ Monkey, .... 
 
 ,, 36. Left Hemisphere of Human Brain, 
 
 „ 37. Upper View of Brain of Chimpanzee, 
 
 ,, 38. „ Human Brain, 
 
 „ 39. Brain of Elephant, .... 
 
 „ 40. „ Whale, .... 
 
 „ 41. Motor and Sensory Apparatus, 
 
 „ 42. Diagram representing common experience of Man and 
 Animal, ...... 
 
 „ 43. Diagram representing Man's Government of Desires, 
 
 PAGE 
 
 129 
 130 
 132 
 134 
 135 
 141 
 150 
 152 
 154 
 155 
 175 
 181 
 189 
 
 425 
 426 
 
THE RELATIONS OF MIND AND BRAIN. 
 
 CHAPTEE I. 
 
 RELATIONS OF PHILOSOPHY AND SCIENCE. 
 
 Philosophy and Science are so related as to constitute a 
 unity. The one is concerned with the facts and problems of 
 rational life ; the other with the facts and problems of material 
 existence, animate and inanimate. They are at one in seeking 
 a rational explanation of observed facts. They adopt the 
 same method, depending upon observation, analysis, classifi- 
 cation, and reasoning. However widely separated the regions 
 of inquiry, searchers for truth are working in harmony, 
 whether they recognise the fact or dispute it. Each group is 
 a body of specialists, but the results of inquiry, wherever pro- 
 secuted, bear upon one grand problem concerning the universe. 
 It is recognised equally by Philosophy and Science, that things 
 existing constitute a system, or organised order of existence. 
 It is granted, therefore, that careful research, whatever direc- 
 tion it take, must result in some contribution to the grand total 
 of human knowledge. And it is equally clear that those most 
 entitled to a hearing on any branch of inquiry are those who 
 have devoted themselves to research in the department with 
 which that inquiry is concerned. Only thus can real advance 
 be made on the vast region of research which the universe 
 presents. Philosophy must wait on Science, and Science in 
 turn wait on Philosophy. 
 
 Here, as most readily occurs to one devoted to the study 
 of the phenomena of mind, it needs to be insisted upon, that 
 the inquirers themselves belong to the universe about which 
 they inquire. And it should be clear — even a truism — that 
 
 A 
 
J THE RELA TIONS OF MIND AND BRAIN. [chap. 
 
 ;he inquirers present the grandest elements in the whole pro- 
 blem. For, to study, and to unfold even partially, the system 
 Df things existing, is to prove superiority in the midst of the 
 system. It is to prove that there is reason in all things. And 
 if so, the rational nature, which can unlock the secrets of the 
 miverse, most of all deserves attention. 
 
 From such elementary considerations, it is plain that all 
 science is in a radical sense philosophy, and all philosophy 
 science. It may even seem a needless distinction to speak of 
 Dne form of inquiry as scientific, and of another as philosophic; 
 making one set of generalised results a science, another set a 
 philosophy. Usage has, however, estahlished the practice. 
 And it is convenient to have the distinction. The sciences 
 have come to be regarded as concerned with some department 
 of the physical universe, in contrast with what pertains to the 
 nature and laws of mind. This distinction has been held with 
 sufficient definiteness for all practical purposes. Yet, science 
 is so obviously a philosophy, that the old terminology was 
 warranted which distinguished a Natural Philosophy from a 
 Mental Philosophy, — a philosophy of nature from a philosophy 
 of mind. On exactly the same ground we may speak of philo- 
 sophy as a science. Scientific knowledge, the higher know- 
 ledge gathered by recognised scientific methods, cannot be 
 restricted to certain spheres. Wherever observation is possible, 
 and reflection as to the laws which regulate recognised facts, 
 3cience is possible. If there may be a science of the formation 
 of bone, muscle, and nerve, leading to the recognition of laws 
 which operate in some manner quite beyond our experience, so 
 may there be a science of perception, association, and in- 
 ference, leading to the recognition of laws applicable to the 
 facts of our experience. Man himself belongs to nature. 
 The science of human life, in the full breadth of meaning 
 belonging to the word "life" in this connection, has its place 
 among the natural sciences. Physiology and Psychology when 
 taken together are sciences of human life ; they cannot be dis- 
 sociated. Only when they are combined can we be said to 
 have a science of the life of man. The claim is therefore a 
 reasonable one, that the whole nature of man be included 
 within the scope of natural science. I am far from thinkin" 
 
!•] RELATIONS OF PHILOSOPHY AND SCIENCE. 3 
 
 that external observation alone will prove sufficient to guide us 
 to a science of human life. But internal observation proceeds 
 upon the same conditions, and is as entitled to confidence as 
 external. By the blending of the two a science of human life 
 may be reached, which will certainly be unattainable if either 
 form of observation be exclusively employed. 
 
 Not unfrequently "scientific methods" have been claimed 
 as belonging to the physical sciences alone. Mental philosophy, 
 as treated in the works of well-known psychologists, has been 
 ridiculed as if it had proceeded in disregard of "scientific 
 methods." The Scotch school of Philosophy has been specially 
 reproached on this ground. The fallacy of such a charge is 
 glaring. Psychologists may not have given as much attention 
 to physiological facts as they should have done, but to charge 
 them on that account with constructing their theories in dis- 
 regard of observation is obviously unwarrantable. Those who 
 would fasten upon psychologists of former days such a charge 
 as this, must be prepared to maintain that thought and recol- 
 lection and volition are not facts, or that these are facts which 
 do not occur according to law, or that both facts and laws are 
 beyond the reach of scientific inquiry. There is no one who 
 will hazard his reputation on the attempt to vindicate any one 
 of these alternatives. The old psychologists most certainly did 
 not proceed in neglect of the laws of observation and inference. 
 And though there may be better reason for urging that physiology 
 has been too much neglected by metaphysicians, the charge is 
 often unreasonably pressed. You might as well charge the old 
 physiologists with having neglected to use anaesthetics in the 
 vivisection employed in the study of the nerve system, as charge 
 the old psychologists with neglecting the full use of physiology. 
 The real state of the case is simply this — that physiology has 
 never up till this time been in a position to give sufficient 
 testimony as to the functions of nerve and brain to throw much 
 light on philosophic problems. Even now the physiology of 
 nerve and brain is far from being in the advanced position 
 which it must occupy before it can contribute towards the 
 answer of many pressing questions concerned with mental 
 action. Only quite recently have we had systematic inves- 
 tigation as to the possibility of localising functions in definite 
 
4 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 regions of the brain. And even yet there are very serious 
 disputes as to what the results of accredited observations may 
 involve. In these circumstances it hardly seems warrantable 
 to charge against psychologists neglect of the teaching of 
 physiology as bearing on the action of mind. 
 
 That psychologists have hitherto adopted an unreliable 
 method of investigation cannot be maintained. If observation 
 of facts, analysis for the discovery of distinct elements, classifi- 
 cation of things similar, and inference resting on wide induc- 
 tion, are enumerated among " scientific methods," psychologists 
 have regularly employed them all. By these methods they 
 have come to very general agreement as to the rational and 
 emotional nature belonging to our race. It has no doubt been 
 said 1 that there is " no agreement " among those who resort to 
 internal observation ; but every one who is familiar with the 
 works of psychologists knows that the statement is inaccurate. 
 As to the laws of observation, of association, of reasoning, of 
 pleasurable feeling, there is all but perfect agreement among 
 them. 
 
 It is, indeed, the fact that psychologists have trusted to their 
 own consciousness, that is, to their own experience, in seeking 
 to ascertain the laws of mental life, and some physiologists tell 
 us that consciousness is not trustworthy. It has even been 
 said that " there is no witness who is so easily suborned to 
 give false evidence as self-consciousness." 2 But this is an 
 assertion on which there is not agreement among physiologists, 
 nor is it clear that evidence in its support can be gathered 
 by use of scientific methods. It were indeed strange were any 
 science to offer itself as defender of the dogma, — that man is not 
 to trust his own experience. What may he trust if not this ? 
 Take the most ordinary and commonplace tests. How but by 
 consciousness does any man know that the blue appearance of 
 his hands on a wintry morning is the accompaniment of cold- 
 ness, or that perspiration is attendant on a high degree of heat ? 
 When a man says that he feels warm, is it a sad misfortune 
 that " he appeals to a witness whose evidence can be taken by 
 no one but himself "? Is it true that this is a witness " whose 
 veracity cannot be tested"? To throw doubt upon experience 
 
 1 Maudsley's Physiology of Mind, 3d ed., p. 16. 2 j oici 17 
 
I.] RELATIONS OF PHILOSOPHY AND SCIENCE. '$ 
 
 is to deny the possibility of knowledge, and so of all science. 
 When the psychologist trusts his consciousness he simply does 
 what every man does, — what every man must do, who is not 
 insane. Trust in consciousness is no speciality of psycholo- 
 gists, but the common prerogative of humanity. Here there 
 can be no rational conflict between science and philosophy. 
 Physiology must refer to consciousness in order to carry through 
 its own investigations. A physiology of the senses must take 
 account of the facts of consciousness connected with sight and 
 hearing. Any scientific handling of the problem of localisation 
 of functions in the brain is impossible without giving careful 
 attention to the facts of individual consciousness. Of the host 
 of physiologists now engaged on this question, I am not aware 
 of one who does not make habitual reference to the conscious- 
 ness of others, besides placing constant reliance on his own. 
 
 There seems to me but one sphere in which we find ourselves 
 on debatable ground, that is, when we consider the case of the 
 insane. And it surely throws no discredit on consciousness, 
 but is rather a testimony to its trustworthiness, if we encounter 
 difficulties as to its testimony only when we come to deal with 
 what is abnormal in life. But even here there are only com- 
 plications, as the result of disturbance from an abnormal phy- 
 sical condition. If we disentangle these complications, we 
 shall find that the trustworthiness of consciousness is confirmed. 
 In our asylums for the insane, administration does not proceed 
 on the assumption that the consciousness of the patients is not 
 reliable. There is not a physician in any one of these Asylums 
 who does not found his diagnosis on the assumption of the relia- 
 bility of his patient's consciousness. Even where there is the 
 most extraordinary hallucination, the physician does not treat 
 his patient as a cheat who is playing off tricks on the medical 
 officers. On the contrary, he distinguishes between attempted 
 deception and real hallucination. In regarding the hallucina- 
 tion as fact, he takes the consciousness of the deluded person 
 as a reliable witness, and proceeds to consider what may be the 
 source of the acknowledged hallucination. On this basis the 
 physician prescribes, and he is vindicated in the assumption on 
 which he proceeds by the number of cures he effects. On this 
 same admission are based the rational methods of treatment, 
 
6 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 now accepted as the only methods which can pass for scientific. 
 All the prescriptions and forms of discipline familiar in asylums 
 for the insane are used in accordance with observation, and 
 that is based not only on what the physician sees, but also on 
 what the patient says. 
 
 There is still another phase of exaggerated criticism of 
 psychological investigations into which some physiologists have 
 allowed themselves to be drawn. I refer to the objection taken 
 against introspection, or observation of the facts of our own 
 consciousness. To object to this is to object to our observing, 
 recording, and comparing the facts of our own experience, in 
 order to ascertain the conditions of our own life. The objec- 
 tion is futile, as it is confuted by every man who employs it. 
 If we would know what is within, how shall we be satisfied 
 but by looking within ? Impossible, says an acute physiolo- 
 gist ; the thing cannot be done ; — if you turn attention on the 
 current of thoughts and feelings passing within, you disturb 
 the current, nay, even break it, and so lose the thing for which 
 you are seeking. 1 This much Dr. Maudsley has borrowed from 
 Comte, and to small advantage. Every man is conscious of 
 his thoughts and feelings, that is, he knows them as elements 
 in his own experience. The physician does not hesitate to ask 
 his patient how he feels. He does not apologise for the ques- 
 tion, as if it hazarded a sudden termination of all experience 
 save sudden perplexity. Every one possesses the ability to 
 describe his own experience, and is well aware that it is pos- 
 sible to concentrate attention on a definite class of facts in his 
 experience, without seriously disturbing the current of his 
 thoughts and attendant feelings. If there is to be any regard 
 to the facts of personal experience, — and all physiologists 
 admit that attention must be given to them, — it is impossible 
 save by reference to consciousness, and such reference involves 
 introspection. 
 
 On the other hand, it is impossible to construct an adequate 
 philosophy of mind by use of introspection alone. Experience 
 does not carry its own explanation. There is very much 
 essentially connected with our experience, which nevertheless 
 does not come within experience. We must, therefore, turn 
 
 1 Maudsley'a Physiology of Mind, p. 17. 
 
I.] RELATIONS OF PHILOSOPHY AND SCIENCE. 7 
 
 observation in other directions. And he who grants the 
 validity of observation when turned upon the inner sphere, 
 will no less freely grant its value when turned upon the outer. 
 
 If, notwithstanding what has been said, it still be main- 
 tained that mental philosophy has not in this respect honoured 
 physiology as it should have done, I do not dispute that there 
 is ground for the charge. But it should be remembered that 
 the departments of inquiry are so distinct, that each must wait 
 upon the other for the materials with which to institute com- 
 parisons. Physiology must complete its own work for purely 
 physiological ends before psychology can be in a position to 
 deal with the relations of the two provinces. "We must first 
 know with accuracy what are the functions of physical organs 
 before we can advance to the further question how far per- 
 sonal experience is involved in their fulfilment. Psychology 
 allows that harmony of physical and mental action is certain, 
 inasmuch as these two forms of action belong to the unity of 
 life. And what psychology undertakes to do is, to formulate 
 its own assertions concerning the relations of mind and body, 
 in view of the verified results of physiological research. Psy- 
 chology justly expects physiology to do as much in dealing with 
 the verified results of introspection. 
 
 Physiology is not even yet in a position to present a suffi- 
 ciently exact account of the several functions of nerve and 
 brain. Most able and devoted students of the science admit 
 that it is still premature to advance such a claim on its behalf. 
 But there is now a large body of ascertained fact calling for 
 some deliberate attempt to harmonise results with the facts of 
 mental experience. And psychologists have even the deeper, 
 because more direct and pressing, interest, in attempting to 
 ascertain how far a harmony between the two departments of 
 inquiry can be reached. 
 
 There are, indeed, some physiologists who easily and sum- 
 marily cast aside the question. They simply assert that it is 
 vain to seek for harmony, inasmuch as there are not two sides 
 to harmonise. With them physiology is everything, psycho- 
 logy nothing. They deny the reality of mind as a distinct 
 order of existence, associated with body, but of a superior 
 nature. They allege that there is no evidence in human life of 
 
8 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 the existence of any power or force which cannot be traced to 
 physical organism. The exercises commonly called " mental " 
 are only higher and finer forms of nerve action. Nerve force 
 is the highest order of force operating in human history. 
 
 Here, then, we come upon the foundation question for all 
 mental philosophy. The present condition of physiological and 
 psychological research requires that this question be carefully 
 considered. Current theories concerning the origin and deve- 
 lopment of life on the earth, and speculation affecting the order 
 and government of the universe as a whole, have more or less 
 bearing on the question, and lend additional interest to it. 
 Besides, it is impossible to overlook the fact, — and it is import- 
 ant to note it, — that researches into comparative anatomy and 
 physiology are leading in many cases to a statement of the pro- 
 blem itself which virtually assumes that brain is the measure of . 
 what is highest in human life. I take but a single example from 
 one who is recognised as a careful observer and an acute reasoner. 
 Eeferring to Bischoff s statement, that the brain of man and 
 the brain of the orang do not perfectly agree at any period of their 
 development, Mr. Darwin says, " Nor could this be expected, 
 for otherwise their mental powers would have been the same." 1 
 Thus, so early as the first chapter of his work, it seems to 
 be assumed by Mr. Darwin that brain power and mind power 
 are to be identified; or, at least^ that the one is the exact 
 measure of the other. And this is done when the compari- 
 son of human brains involves great perplexity for such a 
 view ; and when, besides, it is clear that there is not a little 
 nerve action which involves no mental power. When the fact 
 of reflex action was demonstrated, it was clearly established 
 that nerve action does not in itself imply mental action. 
 Whatever may be involved in a comparison of brain powers, 
 the problem before us cannot be simply identified with the 
 question of resemblance of structure. Our problem is in one 
 way something narrower than this : and, in another aspect, it is 
 much wider. For there is not a little nerve action which is not 
 connected with "mental phenomena;" and there are many forms 
 of nerve action which carry us quite beyond the physiology 
 of brain and nerve for their explanation. And yet in almost 
 1 Descent of Man, vol. i. p. H. 
 
I.] RELATIONS OF PHILOSOPHY AND SCIENCE. 9 
 
 all treatises on the nerve system there is now and again a 
 tendency to resort to forms of expression which unintention- 
 ally seem to imply that these two problems are identical. And 
 this, I think, arises from a constant comparison of the analogies 
 and homologies of brain structure in different orders of beings, 
 while too little attention has been turned on specialities of 
 brain recognised in different animals. A certain homology of 
 brain structure up the whole scale of animal life will be freely 
 admitted as scientifically established. In accordance with this 
 homology, however, the brain of man is recognised as beyond 
 all dispute at the head of the scale ; yet it is assuredly within 
 the scale of animal life, for no one doubts that man possesses 
 an animal nature, though most will refuse to admit that he 
 is nothing more than an animal. But, after the homology of 
 brain structure is admitted as a fact in the economy of animal 
 life, the comparison of the different powers possessed by living 
 beings, and exercised by them in connection with brain action, 
 such, for example, as sight and hearing, remains as a distinct 
 problem. 
 
 In proceeding to deal with this problem, I prefer to approach 
 it by the path which physical science has opened. Granting 
 that the brain is the organ of the mind (" das Seelenorgan," as 
 Rudolph Wagner has named it), the problem may be stated 
 thus, — Given a physiology of brain and nerve, to ascertain 
 whether this constitutes a philosophy of the phenomena com- 
 monly recognised as " mental phenomena." These phenomena 
 may be summarised under the three words, Thought, Emotion, 
 Volition, taking all these terms in their commonly received 
 meanings. I shall attempt first a summary of the results of 
 anatomical and physiological research, and afterwards consider 
 how far these results carry us in the interpretation of the facts 
 of our own life. 
 
THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 CHAPTER II. 
 
 STRUCTURE OF THE BRAIN. 
 
 The object of the present .treatise leads me to concentrate 
 attention on the nerve system, upon which the sensibility and 
 activity of the body depend, whatever more may be included 
 among its functions. Though intimately connected with the 
 whole body, it can be studied and described without necessity 
 for a prior detailed account of all that belongs to the structure 
 and functions of bone and muscle. 
 
 The nerve system may be contemplated from two distinct 
 points of view. We may begin with the periphery or external 
 extremities of the system, where there is contact with the outer 
 world. From those minutest fibres, which are most remote from 
 the centre, we may trace the strands upwards, reaching the con- 
 necting points where several strands combine, and so continue 
 until we find all converging on the spinal cord, and thence passing 
 up into the great nerve centre, the Brain itself. Or, we may take 
 our stand-point at the centre of the system in the brain, con- 
 templating the great mass there accumulated, and, immediately 
 beneath, the spinal cord with its nerve fibres thence issuing; and 
 thereafter we may observe the manifold ramifications, breaking 
 forth in all directions to penetrate the entire muscular system 
 and organs of sense. The latter is the preferable stand-point 
 for those who seek to obtain a view of the system as a whole. 
 This is obvious, for in looking from the centre outwards, com- 
 pleteness of view is maintained ; whereas, looking from the 
 periphery inwards, we are forced to take a variety of positions, 
 each one giving only a limited view of the system. For this 
 reason I take the brain as the starting-point for description. 
 
 Underneath the solid, hard covering of the cranium, and 
 enveloped within three membranes, is the brain proper, or 
 cerebrum. Below this, and to the rear, are grouped three 
 important though smaller and subordinate subdivisions of the 
 
«:] 
 
 STRUCTURE OF THE BRAIN. 
 
 great central mass, the .cerebellum, or little brain; the pons or 
 bridge ; and the medulla oblongata, or elongated mass in direct 
 relation with the upper part of the spinal cord. These four 
 taken together constitute the great nerve centre, the brain proper 
 being the most important by far, not only larger, but much more 
 complicated in structure. When in the following description 
 I use the name " Brain," I intend only the cerebrum or brain 
 proper — the large organ filling the main cavity of the skull. 
 In anatomical and physiological works the name is not unfre- 
 quently applied to the whole central bodies taken together, all 
 that is within the head, hence named Encephalon. 
 
 eyeball. 
 
 Fig. 1.— THE TOUGH OUTER COVERING OP THE BRAIN. 
 {From Professor Turner's Anatomy.) 
 " Dura mater and cranial amuses. 1, Falx cerebri ; 2, tentorium ; 3, 3, superior longitudinal 
 sinus ; 4, lateral sinus ; 5, internal jugular vein ; 6, occipital sinus ; 6', torcular Herophili ; 
 7, inferior longitudinal sinus ; 8, veins of Galen ; 9 and 10, superior and inferior petrosal 
 sinuses; 11, cavernous sinus ; 12, circular sinus, which connects the two cavernous sinuses 
 together ; 13, ophthalmic vein, from 15, the eyeball ; 14, crista galli of ethmoid bone." 
 
 Of the three membranes which cover the brain, the outer- 
 most (dura mater) is the toughest and strongest. From this 
 tough covering strong bands, as the falx and tentorium, pass 
 between different parts of the encephalon. In this membrane 
 are also situated the channels or blood sinuses which convey 
 the venous blood from the brain. Below this tough covering 
 is the intermediate membrane (arachnoid mater), a much more 
 delicate structure, stretching round the whole brain, but with- 
 
THE RELATIONS OF MIND AND BRAIN. 
 
 [chap. 
 
 out descending into the various inequalities which are presented 
 over its surface. Between the outermost and intermediate 
 covering there is a supply of serum, moistening the inner 
 surface of the tougher covering, and the upper surface of the 
 more delicate membrane. Below this second covering is a 
 third membrane (pia mater), which not only encompasses the 
 whole, as the others do, but keeping close to the surface of the 
 brain, descends into the various furrows, and conveys blood- 
 vessels into its substance. These three coverings enclose the 
 spinal cord, as they enclose the brain. 
 
 Within this threefold covering lies the brain, a large soft 
 mass, in two halves or hemispheres, of a reddish grey tint, 
 arranged in folds or convolutions which have a definite posi- 
 tion and direction. By means of these convolutions there is 
 a large exposed surface within the narrow limits which the 
 skull affords, the soft mass being arranged alternately in ridges, 
 and in grooves or furrows {sulci). 
 
 Fig. 2. -THE BRAIN AS SEEN IN POSITION WITHIN TUE SKULL. 
 (From Turner's Anatomy.) 
 'The above view of the brain m situ shows the relations of the surface convolutions to the 
 regions of the skull. R, fissure of Rolando, which separates the frontal from the parietal 
 lobe. PO, parieto-occipital Assure between the parietal and occipital lobes. SS, fissure 
 of Sylvius, which separates the tcmporo-sphenoidal from tlio frontal and parietal lobes. 
 The frontal area lies in front of the coronal suture. SF, MP IF the supero- mid- and 
 infcro-frorital subdivisions of the frontal area of the skull; the letters are placed on the 
 
"•] STRUCTURE OF THE BRAIN. 
 
 13 
 
 superior, middle, and inferior frontal convolutions ; the inferior frontal region is separated 
 from the middle frontal by the frontal part of the curved line of the temporal ridge ; the 
 mid- from the supero-frontal by a line drawn backwards from the upper margin of the 
 orbit through the frontal eminence. SAP, the supero-antero-parietal area of the skull ; 
 S is placed on the ascending parietal convolution, AP on the ascending frontal convolu- 
 tion. IAP, the infero-antero-parietal area of the skull ; I is placed on the ascending 
 parietal, AP on the ascending frontal convolution. SPP, the supero-postero-parietal area 
 of the skull ; the lettors are plaoed on the angular convolution. IPP, the infero-postero- 
 parietal area of the skull ; the letters are placed on the mid-temporo-sphenoidal convolu- 
 tion ; the temporal ridge separates the supero- and infero-parietal regions from each other ; 
 a vertical line drawn from the squamous to the sagittal suture through the parietal 
 eminence separates the antero- and postero-parietal regions. X, the convolution of the 
 parietal eminence, or supra-marginal gyrus. O, the occipital area of the skull lies below 
 the lambdoidal suture; the letter is placed on the mid-occipital convolution. Sq, the 
 squamoso-temporal region of the skull; the letters are placed on the mid-temporo- 
 sphenoidal convolution. AS, the ali-sphenoid region of the skull ; the letters are placed 
 on the tip of the supero-temporo-sphenoidal convolution. The black lines mark the 
 boundaries of the different cranial areas." 
 
 This soft convoluted mass grows with the growth of the head 
 in early life, but attains to its full size at a comparatively early 
 . period. There is diversity of opinion as to the time when the 
 full magnitude is reached. Most authorities place it not later 
 than the eighth year. 1 This may fairly point to the period 
 at which formal instruction should begin, while education in 
 the deeper sense in reality begins with the earliest attempts at 
 discrimination between the feelings and actions of others. 
 
 While, however, the maximum size of the brain is reached 
 thus early in life, there is thereafter a -steady increase in weight. 
 This increase goes on with marked advance till about twenty 
 years of age, and thereafter by slower stages till about forty 
 years of age. Beyond this period, according to observations 
 made on a pretty wide scale, there seems to be a slow dimi- 
 nution, which may be stated at about one ounce in ten years. 
 Thus in very advanced years the brain is considerably lighter 
 than in middle life. 
 
 From tables which have been constructed on data afforded 
 by a large number of cases (taking together the four divisions 
 — brain proper, little brain, bridge, and medulla), it appears 
 that the ordinary weight of the European brain is from 46 to 
 52 ounces. In a considerable number of cases the weight falls 
 below the lowest figure named ; in a considerable number, it 
 rises above the highest figure given. As scientific inquiry has 
 
 1 Opinions vary from three years to eight, but the preponderating view 
 points to the seventh year. See Quain's Anatomy, 8th ed., vol. ii. p. 678. 
 
14 
 
 THE RELATIONS OF MIND AND BRAIN. 
 
 [CHAP. 
 
 been directed largely on a comparison of the human brain with 
 the brain of the ape, it may be well here to give a few 
 examples of the weight of brain among the higher apes. 
 Professor Owen gives two cases of the chimpanzee, the one 
 weighing 9| ounces, the other 13| ounces; Marshall weighed 
 one brain, which, with its membranes, reached 15 ounces. Pro- 
 fessor Polleston had the brain of an orang weighed, and it was 
 1 2 ounces. 1 Bischoff estimates the mean brain weight of the 
 adult male gorilla at about 442 grammes (about 15^ ounces). 2 
 In the case of man, the weight of the brain proper, of which 
 I am chiefly to treat, may be seen by taking an example of the 
 whole four divisions of the nerve centre at 50 ounces. Givine 
 
 o 
 
 the comparison in ounces, it may be stated thus : — the brain 
 proper, 44 ; the little brain (cerebellum), 5 ; and the other two 
 parts, 1. This gives a much greater proportion to the brain 
 
 m - 
 
 Pio. 8-VIEW OF THE RIGHT SIOE OF THE HUMAN BHAIN .'. (Foville). 
 (From Quain's Anatumy.) 
 
 "1, Assure of Rolando; 2, anterior ascending parietal convolution; 3, frontal convolutions con- 
 nected posteriorly with the anterior ascending parietal; -I. „ of two frontal convolu- 
 tions ; 5, posterior ascending parietal convolution; 6, another parietal convolution 
 similarly connected with those on the Inner surface ; 7.7. anterior part of the convolution 
 of the fissure of Sylvius ; s, x, horizontal part of the same convolution ; 9, S, posterior 
 
 part; 10,11 12 anterior, middle, and posterior principal solutions of the island of 
 
 occi iTalToho" S ' SUpraorWtal evolution; 14, part of the temporal lobe; 15, 
 
 i Quoted by Professor Turner in West Riding Asylum Report*, vol. iii. 
 p. 13. 
 - Silz. tier matX-phya. Clause, Munich, March 10, 1877. 
 
II.] STRUCTURE OF THE BRAIN. 15 
 
 proper in man, as compared with the cerebellum, than is usual 
 in the lower forms of mammals. 1 
 
 If next we consider the relative weight of the entire ence- 
 phalon to the weight of the whole body, we have a summary of 
 results in the tables of Clendinning, Tiedemann, and Eeid. — 
 (Quain's Anatomy, vol. ii. p. 580.) From these authorities it 
 appears that the average weight of the brain proper and subor- 
 dinate divisions of the nerve-centre in relation to the body is as 
 1 to 36 ; or, in cases where there has been no diminution of 
 muscular strength prior to death, 1 to 40. In cases of full 
 muscular development the proportion is smaller than in cases 
 where bodily strength' has been reduced under the influence of 
 disease. 
 
 I come now to speak more particularly of the general 
 configuration and structure of the brain proper. I begin with 
 the side view of the organ, taking the right hemisphere for the 
 example. 
 
 Looking at fig. 3, it will be seen that the extent of sur- 
 face is greatest across the central part, and that the height is 
 much greater in the front region than at the back. Eunning 
 the eye along the margin from front to back, it is seen that the 
 front rises clear up with a curve, which is well represented by 
 the appearance of the forehead, while the rear falls greatly away, 
 as by a rapid descent from the main elevation. 
 
 Within this mass there are clearly marked subdivisions. 
 Amongst the numerous convolutions there are two deep fissures, 
 which constitute natural boundaries for separate portions of the 
 organ. Most conspicuous to the eye is that which opens into 
 the mass from the base at a point distant from the front about 
 one-third of the whole extent. This is the Fissure of Sylvius, or 
 the Sylvian Fissure. It begins at S, at number 9 on the right. 
 With a slightly upward tendency at first, it "runs towards the 
 rear, terminating about the point touched by the dotted line 
 coming from the number 9 on the left side of the figure. This 
 fissure may be said to divide the middle portion of the brain 
 into an upper and an under region, leaving the whole of the 
 
 1 See Dr. J. Eeid's Table as given in Quain's Anatomy, vol. ii. p. 581. 
 Also Reference Tables arranged by Mr. Barlow, in Professor M'Kendriek's 
 Outlines of Physiology, p. 713. 
 
16 THE RELA TIONS OF MIND AND BRAIN. [chap. 
 
 front part undivided from base to summit. This fissure is the 
 first to appear in the development of the brain of the foetus, and 
 thus beyond doubt it is an essentially important dividing furrow. 
 
 Looking now along the top of the mass, and a little towards 
 the rear, a fissure of considerable breadth and depth, the Fissure 
 of Eolando is seen appearing at K, taking a course which 
 decidedly tends downwards and forwards towards the frontal 
 region. Its course is indicated by the figures 1, 1, 1. 
 
 By these two fissures there is division of the brain proper, first 
 into higher and lower, and, second, into front and rear. The latter 
 division applies to the upper portion of the brain lying above 
 the Sylvian fissure. Towards the back part of the brain, but 
 not visible on the outer surface, is the Parieto-occipital fissure, 
 which indicates a twofold subdivision of the upper portion of 
 the brain behind the fissure of Eolando. The front of the brain, 
 as far back as the fissure of Eolando, is known as the Frontal 
 Lobe ; behind the Frontal, as far down as the Sylvian fissure, 
 and as far back as just a little below the figure 8, is the upper 
 central division, known as the Parietal Lobe ; behind that is 
 the Occipital Lobe ; in advance of this, on the lower part, and 
 below the Sylvian fissure, is that known as the Temporal 
 Lobe, or Temporo-Sphenoidal. These four lobes are the four 
 divisions of the superficial area, in both hemispheres. Besides 
 these four, however, there is another concealed from view, hid 
 under the folds of the Sylvian fissure, constituting a Central 
 Lobe, which, on account of its insulated position, is known as 
 the Island (Insula), and is distinguished by the name of its 
 discoverer, the Island of Eeil. In figure 3, the island is 
 shown by the lines running from 10, 11, and 12, marking 
 the three convolutions, which together constitute the Central 
 Lobe. 1 The reader must therefore imagine the fold just 
 above these convolutions drawn down so as to cover them 
 entirely, and the front portion of the brain proportionately 
 lowered. Thus drawn down, the fold will meet the under fold 
 of the Sylvian fissure running up from S. When these three 
 
 1 The Island or Central Lobe is that which appears first in the growth of 
 the brain, so that the rest are grouped round it. Yet it is represented as 
 peculiar to man and the higher apes. It has been made the subject of 
 special investigation by Dr. H. C. Major.— Lancet, July 14 and 21, 1877. 
 
II.] 
 
 STRUCTURE OF THE BRAIN. 
 
 convolutions are thus covered, the natural appearance of the 
 left hemisphere is obtained. (See fig. 5, p. 18.) This five-fold 
 arrangement of the -lobes is that of Gratiolet, and is now gene- 
 rally accepted. 1 
 
 From the view of the profile of the brain proper, it is needful 
 
 ' : '^i;jfe|i4j.l 
 
 mm, . P 
 
 v.„. ^—iy-^^~ SURFACE OF THE BRAIN. & 
 
 \rrom i^uam a Anatomy, after R. Wagner.) 
 
 " This view was taken from the brain of a famous mathematician, Professor C. F. Gauss, who 
 died in 1854, aged 78. It is selected as an example of a well-formed brain of the full size with 
 fully developed convolutions. 
 
 a, superior or first frontal convolution; a', second or middle frontal ; a", third or inferior 
 frontal ; A, A, ascending frontal convolution ; B, B, ascending parietal convolution ; b, 
 first or upper parietal convolution ; b', second or middle ; o", third or inferior ; c, first 
 or upper temporal convolution ; d, first or upper occipital convolution ; d' , second or 
 middle ; d", third or lower ; I, I, the superior longitudinal fissure ; r, the fissure of 
 Rolando ; p, parietooccipital fissure." 
 
 to pass to another, obtained by looking down npon the mass from 
 above. From this point of observation there comes into view 
 
 1 Quain's Anatomy, vol. ii. p. 523; Turner's Anatomy, vol. i. p. 267- 
 
 B 
 
18 TH E RELATIONS OF MIND AND BRAIN. [chap. 
 
 Front. 
 
 Fia. 5.— EIGHT SIDE OF THE HUMAN BBAIN, DRAWN IN OUTLINE. 
 
 (From Turner's Anatomy.) 
 
 Front. 
 
 SF 
 
 Fio. 6.— UPPER SURFACE OF THE BRAIN, DRAWN IN OUTLINE. 
 (From Turner's Anatomy.) 
 ' Profile and vertex views of Cerebrum. Fr, the frontal loVje ; Par, parietal ; Oc, occipital ; 
 2'S, temporo-sphenoidal lobe ; S3, Sylvian fissure ; RR, fissure of Rolando ; PO, parieto- 
 occipital fissure ; IP, intra-parietal fissure ; PP. Parallel fissure ; SF and IF, supero- and 
 inforo-frontal fissures ; 1, 1, I, inferior, 2, 2, 2, middle, and 3, 8, 3, superior frontal con- 
 volutions ; 4, 4, ascending frontal convolution ; B, 5, 5, ascending parietal, 6', postero- 
 parietal, and 6, 8, angulaT convolutions ; A, supra-marginal, or convolution of the parietal 
 eminence ; 7, 7, superior, 8, 8, 8, middle, and 9, 9, 9, inferior temporo-sphenoidal convolu- 
 tions; 10, superior, 11, middle, and 12, inferior occipital convolutions ; a, /5, y, 6, four 
 annectent convolutions." 
 
ii.] STRUCTURE OF THE BRAIN. 19 
 
 the double structure of the organ, by separation into two 
 hemispheres. A straight line of separation, known as the great 
 longitudinal fissure, runs along the summit, making a division 
 of the brain into two perfectly distinct halves, as illustrated in 
 figure 4 on page 1 7. 
 
 This figure, as the representation of the brain of a man of 
 known intellectual power, Professor C. P. Gauss of Gottingen, is 
 of value as an illustration not only of the general configuration 
 of the organ, but also of specialities, showing diversities of 
 form in the two sides of the brain. 
 
 Directly through the centre, separating the two hemispheres 
 or sides, from I to I (fig. 4), is the great longitudinal fissure. 
 The two halves of the brain proper lie closely together, but are 
 separated by the band of dura mater named falx cerebri 
 (fig. 1,1). While, however, they lie parallel and close to each 
 other, they can be drawn to some extent asunder, except that, 
 towards the lower portion, they are held together by a transverse 
 band, called corpus eallosum (fig. 9, 1, p. 30). The three convo- 
 lutions of each lobe are marked by the small letters (fig. 4), thus 
 a, a', a", for those of the frontal, and so with 0, c, and d, but 
 that the lower or temporal lobe does not come much into view, 
 and is only partially indicated on the turning at the right c, c' 
 (fig. 4). It will appear on comparing the convolutions, that 
 great prominence belongs to those two in the middle, so full 
 in shape and continuous in their course, marked by the 
 capitals A, A, and B, B, known as the ascending frontal and 
 ascending parietal convolutions. 
 
 A comparison of the two hemispheres as given in fig. 4, shows 
 that within certain limits a difference of arrangement may 
 exist in the two hemispheres, which are in effect distinct 
 organs, set in juxtaposition, and united together by inter- 
 mediate fibres. A glance from right to left, over the suc- 
 cessive lobes, reveals undoubted differences. This fact is very 
 well shown both in the middle (parietal) and in the rear 
 (occipital). While the two hemispheres are strictly analogous 
 and capable of being divided in the same manner, there are 
 differences in the fulness and foldings of certain convolutions. 
 On the opposite page are two figures in outline from Professor 
 Turner's Anatomy, which facilitate the work of reference to 
 
20 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 the convolutions. Professor Turner's figure of the profile 
 differs from figure 3, by having the sides of the Sylvian fissure 
 drawn together in the natural position, covering the central 
 lobe, the island of Eeil. 
 
 Though there are clearly marked dividing furrows common to 
 every human brain, yet considerable diversities occur in the 
 aspect of the convolutions. In a series of examples all showing 
 elaborate foldings, there would be found much diversity in the 
 form and relative size of different folds. This is well illustrated 
 by the beautifully executed drawings (Plates I., II., v.), which 
 accompany Eudolph Wagner's work on the human brain. 1 
 These Plates equally illustrate the fact that there is an appre- 
 ciable difference in the arrangement of the convolutions on 
 the two sides of the brain. 
 
 Importance must attach to variations which may be found 
 as the result of the comparison of examples. The materials 
 at command are not by any means sufficient to dispose of the 
 question which here arises, for the results are far from uniform. 
 Dr. Herbert C. Major, who has given great attention to these 
 questions, has been led to remark on the number of exceptional 
 cases which appear on any principle of comparison which may 
 be adopted. He says, "As a general rule, great intellectual 
 power is associated with a large and heavy brain. . . . Unfor- 
 tunately, however, this is by no means an invariable rule, for 
 instances . are not wanting in which the brain representing 
 superior intellect has not only not surpassed another lower in 
 the intellectual scale, but has fallen below it." 2 Allowing for 
 such exceptional cases, and granting that special attention may 
 yet require to be given to these, there are some general results 
 of obvious importance. The first and readiest ground of com- 
 parison is found in the mass and weight of the brain. These 
 are not in themselves sufficient tests. Great mass and weight 
 sometimes belong to a diseased organ, and are in reality often 
 symptoms of disease. Quality of brain must, therefore, be 
 considered as well as bulk. Besides, it is clear that mass and 
 weight of brain vary in some degree proportionately to the size 
 
 1 Voratudien zu einer wissenschaftlichen Morphologic und Phyaiologie 
 des Menschlichen Gehirns als Seeleuorgan, lste Abh. 1860. 
 
 2 West Riding Asylum Reports, vol. ii. p. 157. 
 
n.] STRUCTURE OF THE BRAIN. 21 
 
 and weight of the body. This is amply confirmed by com- 
 parison of the brains of animals of large proportions with the 
 brains of animals of small size. Proportion between brain and 
 body must therefore also be considered, as well as mass or 
 weight in itself. And here it should be remarked that the 
 relative weight of the brain to that of the body is greatest in 
 early life. In childhood we have a much heavier brain pro- 
 portionately to weight of body than we have in mature life. 
 The brain starts in better condition than the body ; but when 
 growth begins the body greatly outstrips the brain in the rate 
 of progress. From Tiedemann's observations, published in 
 1837, it appears that at birth the proportion of brain to body 
 is "about 1 to 5 - 85 in the male, and about 1 to 6 - 5 in the 
 female." Thereafter the proportion diminishes in the follow-* 
 ing ratio: at 10 years of age it is about 1 to 14; at 20 years 
 about 1 to 30, and later than that about 1 to 36, after which 
 the relative decrease is slight. 1 Thus it appears that it is 
 not when we are at our strongest, but when we are at the 
 feeblest stage of life that our brain is proportionately the 
 heaviest. 
 
 The— first set of these figures calls attention to a greater 
 weight of brain in man than in woman. The following sum- 
 mary of results is given by Professor Turner: — "The average 
 weight of the adult European male brain is 49 to 50 ounces 
 (about 3 lbs.), that of the adult female 44 to 45 ounces, so that 
 the brain of a man is on the average fully 10 per cent, heavier 
 than that of a woman." 2 The following additional facts given 
 by the same author must be taken along with this. The 
 average weight of the body is less in women than in men. 
 According to Thurnam's calculations, the average stature of 
 women is " 8 per cent, less than that of men." Besides, it is 
 added, there have been many instances of upwards of 50 ounces 
 (weight of brain) "in women where there was no evidence of high 
 mental endowment." 3 Further, the limitations in most tables 
 to Europeans, suggests that some regard must be had to educa- 
 tional and social influences. Thus Professor Turner, founding 
 on the observations of Barnard Davis as to the African races, 
 
 1 Quaiii 's Anatomy, vol. ii. p. 580. 2 Anatomy, vol. i. p. 296. 
 
 3 Turner's Anatomy, vol. i. p. 297. 
 
22 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 says, "Though the male brains are heavier than the female, 
 there is not the same amount of difference in the average brain 
 weight between the two sexes in the uncultivated as in the 
 cultivated people." 1 On this question much will depend upon 
 proportionate weight of brain and body, and this" inquiry is 
 confessedly complicated by the great variations occurring in 
 both sexes. Quain gives us the following results from the 
 tables of Clendinning, Tiedemann, and Eeid — " In a series of 
 81 males, the average proportion between weight of the brain 
 (encephalon) and that of the body, at the ages of 20 years and 
 upwards, was found to be 1 to 36 - 5-; and in a series of 82 
 females to be as 1 to 36 - 46." 2 These figures point to a smaller 
 proportionate difference than comparison of mere weight of 
 brain would have led us to expect. 
 
 Taking now general results as to weight, it seems clear that 
 when the brain falls below 30 ounces there is imbecility. 
 Such light weight of the nerve centres means general feebleness, 
 want of physical development, incapacity for active effort, 
 slight influence of education, and very limited responsibility 
 for conduct, if not the entire absence of such responsibility. 
 Over against this fact it is important to place another, that 
 insanity is often the accompaniment of an unusually large 
 brain. Numerous cases are recorded of mania with a brain 
 weight of from 50 to 55 ounces, and a considerable number in 
 which the weight was 60 ounces and above. In the West 
 Eiding Asylum Eeports there are such examples as these, — a 
 case of senile dementia, 61 ounces; melancholia, 60 ounces. 
 At the same time, the great majority of cases of insanity pre- 
 sent figures greatly below these. In the numerous examples 
 of brain wasting there is of necessity loss of bulk and weight. 
 Weight, therefore, when taken by itself, is not a sufficient test, 
 though it must be one of the essential elements in our calcula- 
 tions. 3 
 
 1 West Riding Asylum Reports, vol. iii. p. 7. 
 
 a Quain's Anatomy, vol. ii. p. 580. 
 
 3 Some of Wagner's conclusions on this subject will be found in Quain's 
 Anatomy, vol. ii. p. 571. It is striking to find the number of insane stand- 
 ing in the highest division of Wagner's Tables. Hirngewiohts Tabelle.— 
 Vorstudien, lste Ab. 39. 
 
n.] 
 
 STRUCTURE OF THE BRAIN. 
 
 23 
 
 All tabulated results show that, as a rule, those who are 
 regularly engaged in active duty have a brain of good size and 
 weight. In advance of this, a large number of men noted for 
 high intellectual power have been distinguished by weight of 
 brain. Dr. Thurnam has given the results of his observations 
 in a paper " On the Weight of the Human Brain." 1 The follow- 
 ing table, compiled mainly from his statistics, and from others 
 furnished by Professor Turner, presents some of the results in 
 striking combination : — 
 
 Cuvier, Naturalist, 
 
 Abercrombie, Physician, 
 
 Goodsir, Anatomist, 
 
 Spurzheim, Physician, . 
 
 Dirichlet, Mathematician, 
 
 J. Y. Simpson, Physician, 
 
 De Moray, Statesman, . 
 
 Daniel Webster, Statesman, 
 
 Campbell, Lord Chancellor, 
 
 Agassiz, Naturalist, 
 
 Chalmers, Theologian and Preacher, 
 
 Fuchs, Pathologist, 
 
 Gauss, Mathematician, . 
 
 Jeffrey, Judge and Critic, 
 
 Babbage, Mathematician, 
 
 I am indebted to Sir Eobert Christison, Bart., for the weight 
 of Lord Jeffrey's brain. Sir Eobert, who, along with Pro- 
 fessor Miller, carefully weighed the brain, has kindly favoured 
 me with the following extract from his letter to Sir B. Brodie 
 and Dr. Bright: — "The brain was much congested, and the 
 arachnoid membrane contained much gelatiniform effusion. The 
 encephalon weighed 51| ounces, the cerebellum 6£ ounces." 
 
 In contrast with the above examples, we must keep in view 
 such cases, mentioned by Wagner, as Hermann the philologist ; 
 Tiedemann the physiologist ; and Hausmann the mineralogist, 
 in whom the brain was below ordinary weight, being respec- 
 tively 46J, 44, and 43 ounces. 2 Besides, there are many examples 
 
 1 Journal of Mental Science, April 1866. 
 
 2 It should, however, be stated that Tiedemann was 80 years of age, and 
 Hausmann 77, so that the brain had doubtless diminished in weight from 
 senile atrophy. The same remark may apply in the case of Jeffrey and 
 
 Age. 
 
 Ounces. 
 
 63 
 
 64-5 
 
 64 
 
 63 
 
 53 
 
 57'5 
 
 56 
 
 5506 
 
 54 
 
 55-6 
 
 59 
 
 54 
 
 50 
 
 53-6 
 
 70 
 
 53-5 
 
 80 
 
 53-5 
 
 66 
 
 53-4 
 
 er, . 67 
 
 53 
 
 52 
 
 52-9 
 
 78 
 
 52 6 
 
 76 
 
 51-8 
 
 79 
 
 49-5 
 
24 THE RELA TIONS OF MIND AND BRAIN. [chap. 
 
 of great brain weight without any intellectual distinction. 
 The number of such 'cases is readily illustrated by reference 
 to the highest figures in the table of 964 cases, prepared by 
 Eudolph Wagner, 1 drawn from the observations of Virchow, 
 Bergmann, Tiedemann, and others. 
 
 Besides mass and weight, the principal external features of 
 difference are complexity of the convolutions, and depth of the 
 groove or furrow by which they descend into the mass. There 
 is a large amount of evidence in support of the position that 
 in the less cultivated races the convolutions are far less ample 
 in their folds than are the convolutions of the more cultivated 
 races. 2 The converse seems to hold good in very many cases. 
 The evidence supplied by B. Wagner, 8 and extended by his son 
 Hermann, is, however, very strong in support of the conclusion 
 that the brain of the man distinguished for intellectual power 
 and activity is, as a rule, much more ample in its folds than 
 the brain of his ordinary fellow-countrymen. Apart altogether 
 from the possibility of an increased number of centres in such 
 a brain, there is at least a larger superficial area. The exceptions 
 to the rule are, however, both considerable in number and 
 marked in character. There have been examples of men of 
 high ability whose brain was not more complex in the folding 
 of the convolutions than an ordinary brain, and there have 
 been cases of a brain unusually fine in the waving lines of the 
 convolutions, without attendant evidence of personal distinction. 4 
 
 From outward configuration, I pass to the internal structure 
 of the brain. When a horizontal section of one of the hemi- 
 spheres is made so as to expose a flat surface below the 
 convolutions, the entire central portion is seen to consist of 
 
 1 Vorstudien, lste Ab. 
 
 2 Turner's Anatomy, vol. i. p. 295. 
 
 3 Vorstudien, lste Ab. 
 
 4 The question, what in process of the growth of the organ determines the 
 form of the convolutions, is one to which as yet no very satisfactory answer 
 has been given. It has been suggested by Dr. Halle (London Medical 
 Record, 1875) that the shape of the skull determines the shape of the 
 convolutions, by certain cranial axes resisting the process of growth and 
 leading to the doubling back of the brain substance. This suggestion does 
 not, however, carry an explanation of the marked diversities found among 
 the convolutions. 
 
ii] STRUCTURE OF THE BRAIN. 
 
 25 
 
 white matter, the surrounding grey matter running in upon it 
 with promontories according to the depth of the convolutions. 
 The effect is best appreciated by looking first at the grey mat- 
 ter, then at the white. If we allow the eye first to trace the 
 distribution of grey matter, there is seen, all round, a rim of this 
 matter, here and there increased in breadth by the furrow or 
 grpove between two convolutions. The deeper the furrow, the 
 further the grey matter penetrates. This will be readily 
 appreciated by reference to figure 10, p. 31. Again, looking 
 at the same arrangements from the point of view afforded by 
 the white matter, it seems as if the white, besides occupying 
 the whole centre, formed a series of bays, as when the sea runs 
 up into the land. These bays vary considerably in size, being 
 smaller and more numerous towards the front and rear, while 
 they are fewer in number, and wider on the side of the hemi- 
 sphere. The grey matter completely encompasses the white 
 matter, spreading not only over the entire exterior, but over 
 the base, and inner side of each hemisphere. The depth of the 
 grey matter varies at different points. Dr. Major made a series 
 of investigations by passing a graduated glass tube through 
 different parts. His conclusions may be stated thus : — " The 
 depth of the grey matter of the cerebrum varies in different 
 situations." The depth is decidedly greater in the frontal and 
 upper middle (parietal) lobes, than in the back lobe. The 
 lower middle (temporo-sphenoidal) is also deeper than the 
 back lobe. The concealed central lobe (island of Eeil) shows 
 the grey matter always deep, in most cases, at least as deep as 
 anywhere else. 1 
 
 This contrast of white and grey matter brings under notice 
 two essentially different substances in the brain. The outer 
 portion, wrapped together in convolutions, being the grey 
 matter, is full of nerve cells. These are so numerous as to 
 baffle calculation. From the number seen within a small 
 section placed under the microscope, it is reckoned that there 
 must be many thousands of them in the human brain. The 
 cells are packed together in a glutinous substance, which 
 Virchow has named nerve-glue {neuroglia). Each of these 
 
 i " New method of determining the Depth of the Grey Matter." — West 
 Biding Reports, vol. ii. p. 157. 
 
26 
 
 THE RELATIONS OF MIND AND BRAIN. 
 
 [chap. 
 
 minute cells is found to have a nucleus or central point, 
 around which its substance is gathered. The cells vary 
 somewhat in form, according to the number of the fibres 
 which they send forth, and which spread out in different 
 
 directions. Of these cell-fibres there 
 are often as many as four or five 
 springing from the walls of the cell. 
 The cells being crowded together, are 
 probably connected by the fibres which 
 they give forth. These fibres consist of 
 nerve protoplasm, and some of them 
 serve as the connecting lines be- 
 tween the cells and the nerve fibres, 
 that is, the nerves proper; and the 
 connection is so close that in some 
 cases the cell-fibre passes into the 
 nerve-fibre. The general aspect of 
 the cells with their interlacing fibres 
 will be seen by reference to the ac- 
 companying representation of a sec- 
 tion taken from the front portion of 
 the brain, showing the nerve cells as 
 fig. 7.— section of the grey they are imbedded in the nerve- 
 matter of the BEAIN, mag- , / fi 7 n Thprp is considerable 
 
 niBed to show the cellular struc- g iue \ U S- ')■ J-Uere IS COnslueidUlC 
 
 ture. diversity not only in the form of 
 
 (From, Turner's Anatomy.) . nl . , ,, • 
 
 „ _r. , t . „. ,.„, „., . A the cells, but also m the manner in 
 
 "Vertical seetionthroughthethirdand ' 
 
 fourth layers of grey matter of the which they are grouped together. 
 aT n sSsSd C TyramuS ne^e The largest and most important of 
 
 cells ; the neuroglia, with itB cor- fc^e ce ^ g are k n0 Wn as pyramidal, 
 puscles and some capillary blood- ~ . 
 
 vessels, are represented. •• and these.he deepest. Ine grey 
 
 matter presents a laminated appearance, and as a rule consists 
 of five or six layers, which are composed of the characteristic 
 pyramidal nerve cells of the cortex of the cerebrum, of nerve 
 fibres, of matrix or neuroglia (nerve-glue), and of blood- 
 vessels. . . . From the observations of Lockhart Clarke, 
 Amdt, Cleland, and Meynert, there can be no doubt that 
 the pyramidal nerve cells vary in relative size and in 
 numbers in the different layers of the grey cortex, and that 
 the largest-sized pyramidal cells lie in the third and fourth 
 
"•] STRUCTURE OF THE BRAIN. 27 
 
 layers." 1 Dr. Herbert C. Major has shown that, in the outer 
 layer of the grey matter the nerve cells are fewer, and the 
 nerve-glue occupies the principal place ; towards the middle 
 there are more of the nerve cells, but they are small in size ; 
 and in the deeper layers there is a crowd of the larger 
 pyramidal cells, which send out numerous branches. 2 Betz 
 has made the nerve cells the subject of special study, and 
 he states that giant pyramidal nerve cells are found largely 
 in the portion of the brain lying to the front of the fissure of 
 Bolando, — that they are chiefly in the fourth layer, — that they 
 have two principal fibres, and from seven to sixteen smaller 
 subordinate fibres, — and that of the two principal fibres, the 
 one is slender, and passes from the nucleus direct to a nerve 
 fibre, the other is broad at its origin, and separated into divi- 
 sions which go off towards the outer portion of the grey 
 matter. 3 According to Betz these giant pyramidal cells are 
 gathered into groups. In this same direction, Dr. Lockhart 
 Clarke remarks that " not only in different convolutions does 
 the structure assume, to a greater or less extent, a variety of 
 modifications, but even different parts of the same convolution 
 may vary with regard either to the arrangement or the relative 
 size of their cells." 
 
 The white matter which occupies the central part of the 
 brain is fibrous in structure. It consists of nerve fibres massed 
 together in the interior, and entirely encompassed by the grey 
 matter. This great accumulation of nerve fibre is composed 
 partly of the nerve fibres which are connected with distinct 
 regions of the body, and partly of fibres which unite different 
 portions of the brain so as to constitute a compact vital unity. The 
 latter are so numerous that the mass of nerve fibre which passes 
 down from the brain to the spinal marrow is very much smaller 
 than the body of nerve fibres congregated within the brain. The 
 nerve fibres either extend from part to part within the central 
 organ, or from it downwards and outwards to the peripheral 
 distribution. These nerve fibres are very minute threads. In 
 the brain itself they are sometimes as minute as a twelve 
 
 1 Turner's Anatomy, vol. i. p. 280. 
 
 2 West Ruling Reports, vol. ii. p. 46. 
 
 3 Anatomisclier Nachweiszweier Gehirncentren, 1874, p. 578. 
 
THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 -REPRESENTATION OP 
 NERVE FIBRE. 
 (From Turner's Anatomy.) 
 
 thousandth part of an inch, whilst a nerve which passes down 
 to some part of the muscular system may be one fifteen 
 hundredth part of an inch. 1 
 
 The ordinary structure of the nerve 
 as found in any part of the body 
 involves a threefold arrangement. 
 There is in the interior the axial 
 thread itself; gathered around this 
 is a white marrow-like covering 
 (the white substance of Schwann) ; 
 and these two are enclosed within 
 an investing membrane. 
 
 In the above figure (8), No. 1 shows 
 the threefold aspect — the axial fibre 
 Meduiiated nerve fibres, showing in the centre, the white substance 
 the douwe contour. 2. a similar , M ^ it j sur rounded, and the 
 
 fibre in which A is the primitive U J ' 
 
 membrane, b the medullary sheath, enclosing membrane. In 1859 it was 
 be^d r orStnd oTthS shown by Lister and Turner in a joint 
 3. Transverse section through the p a p 6 r that there was a difference in 
 
 meduiiated fibres of a nerve, , . n ... i , ,i_ 
 
 showing the axial cylinder in the chemical composition between the , 
 
 centre of each fibre. Between the axial £ bre an( J fa e maiTOW-like enclo- 
 flbres is the interfibrous connective # 
 
 tissue." sure in which it is imbedded. 2 Work- 
 
 ing with a mode of preparation devised by Dr. Lockhart Clarke, 
 they ascertained that the axial fibre became of a red hue by an 
 ammoDiacal solution of carmine, while the marrow substance 
 was unaffected, and that the marrow-like substance became 
 opaque and brown under chromic acid, while the fibre con- 
 tinued unchanged in appearance. In 1868 Dr. Eanke of 
 Munich pointed out that the axial fibre has an acid reaction, the 
 marrow substance an alkaline reaction. 3 In ISTo. 2 of the above 
 figure the axial fibre is shown protruding distinct from its 
 enclosures. This fibre is first developed, and is thus the 
 essential feature in the structure. No. 3 shows a section of 
 several fibres as they are gathered together, presenting the 
 extremity of the fibres and their membranes as they lie in 
 
 1 Quain's Anatomy, vol. ii. p. 127 ; Turner's Anatomy, vol. i. p. 196. 
 
 2 Observations on the Structure of Nerve Fibres. — Quarterly Journal of 
 Microscopical Science, October 1859. 
 
 3 Die Lebensbedingungen der Nerven. Leipzig, 1868. 
 
II.] STRUCTURE OF THE BRAIN. 29 
 
 the connective tissue. This illustrates the manner in which 
 provision has been made for isolation of distinct lines of com- 
 munication. It seems generally held that the membrane of 
 the nerve fibres is not present in the brain itself and spinal 
 cord. Professor Turner speaks with caution on the point. 
 He says that the investing membrane "is believed to be 
 absent from the nerve fibres in the brain and spinal cord." 
 Observations are specially difficult here, as the different 
 structures of the fibre are not visible in the living state, and 
 changes in the tissue occur rapidly after death. 
 
 If a cutting deeper than that which first reveals the contrast 
 between grey matter and white be now made, we come upon a 
 broad commissural band of connecting tissue (corpus callosum), 
 which connects the two sides or hemispheres of the brain (fig. 9). 
 The band here exposed consists of a closely compacted body 
 of nerve fibres passing transversely from the one hemisphere 
 to the other, and the transverse fibres have on their surface a 
 few longitudinal fibres. The two hemispheres are thus con- 
 stituted a single organ. This connecting band does not stretch 
 the whole length of the hemispheres ; but, being carried some- 
 what nearer the front than the back of the organ, holds the two 
 sides firmly united in the centre, leaving them free or isolated 
 only towards the forehead and towards the back of the head. 
 Besides, the hemispheres are quite unconnected in the upper 
 portions, until the level of the band now described is reached. 
 They are thus in some respects two organs, while they at the 
 same time constitute a unity. There is separateness, and yet 
 there is solidarity. The connecting band is thicker and stronger 
 at its two extremities than in the middle, and is somewhat 
 stronger behind than in front. The transverse fibres of which the 
 band is almost entirely composed have been traced not merely 
 into the white or fibrous substance, but also into the grey matter, 
 thereby constituting connecting lines between the convolutions 
 on the opposite sides. This presents part of the explanation of 
 the much larger mass of white matter within the nerve centre 
 than that which passes forth to the spinal marrow. A further 
 explanation is found in the existence of connecting lines which 
 unite separate parts of the same hemisphere. The fact that 
 fibres pass from hemisphere to hemisphere, connecting different 
 
THE REI.A TIONS OF MIND AND BRAIN. 
 
 [chai>. 
 
 portions of the grey or cellular matter, points towards the con- 
 clusion that there is co-ordination and co-operation of the 
 
 Cerebellum. 
 Fig. 9. —CONNECTING BAND WHICH UNITES THE TWO HEMISPHERES. 
 (From Quoin's Anatomy.) 
 The upper surface of the corpus callosum has been fully exposed by separating the cerebral 
 hemispheres and throwing them to the side ; the gyrus fornieatus has been detached, and the 
 transverse fibres of the corpus callosum traced for some distance into the cerebral medullary 
 substance. 
 
 1, the upper surface ofthe corpus callosum ; 2, median furrow or raphe ; 3, longitudinal stri* 
 bounding the furrow ; 4, swelling formed by the transverse bands as they pass into the 
 cerebrum, 5 ; anterior extremity or knee ofthe corpus callosum ; 6, posterior extremity; 
 7, anterior, and 8, posterior part of the mass of fibres proceeding from the corpus callo- 
 sum ; 0, margin of the swelling; 10, anterior part of the convolution of the corpus 
 callosum; 11, hern or band of union of this convolution; 12, internal convolutions of 
 the parietal lobe ; 18, upper surface of.the cerebellum." 
 
 opposite parts in providing nerve stimulus or innervation for 
 the ramifications of nerve fibre which spread over the body. 
 
 If next we penetrate beneath this connecting band, we come 
 upon a complicated order of arrangements, presenting to view 
 several distinct bodies, separated by a series of spaces (ven- 
 tricles) filled with fluid. Of these ventricles there are five in 
 
II.] 
 
 STRUCTURE OF THE BRAIN. 
 
 3i 
 
 all. Some of them are shown on fig. 1 0, along with a variety 
 of bodies congregated towards the base of the brain. 
 
 In the central part of fig. 10, towards the back, sweeping 
 in a semicircular form round the innermost visible point of the 
 longitudinal fissure, is seen the posterior swelling of the con- 
 Front. 
 
 Fig. 10.— APPEARANCE OF THE HEMISPHERES BELOW THE CONNECTING 
 BAND, WITH THE LATERAL AND FIFTH VENTRICLES. 
 
 {From Quain's Anatomy.) 
 
 '1, the fifth ventricle ; 2, the two laminae of the septum lucidum meeting in front of it ; 3, 
 lesser hippocampus of the posterior eornu; 4, horizontal section of the posterior swelling 
 of the corpus callosum • 5, middle part of the fornix, where it has been separated from 
 the corpus callosum ; 6, posterior pillar of the fornix; 7, hippocampus major descending 
 in the middle cornu oi the lateral ventricle ; 8, eininentia collateralis ; 0, lateral parts of 
 the fornix; 10, choroid plexus; II, taenia semicircularis ; 12, corpus striatum." 
 
 necting band of the hemispheres, (4). The two most con- 
 spicuous bodies in front are here the most important for my 
 present purpose. These represent the largest nerve ganglion 
 of grey and white matter at the base of each hemisphere 
 
32 
 
 THE RELATIONS OF MIND AND BRAIN. 
 
 [chap. 
 
 (12, corpus striatum). In close relation with these, lying to 
 the rear, but a little lower (and scarcely appearing in this 
 figure) is a second and somewhat smaller ganglion, similarly 
 constituted, {optic thalamus). This ganglion as situated at the 
 
 Fio. 11.— THE GREAT BASAL GANGLIA, WITH CEREBELLUM. 
 (From Turner's Anatomy.) 
 
 "A dissection to show the basal ganglia, and upper surface of cerebellum, n, corpus 
 striatum ; 6, optic thalamus ; c, taenia semicircularis ; d, 5th ventricle ; e, e, anterior 
 pillars of fornix ; /, anterior, g, middle, and J-, posterior commissure ; I, pineal gland, 1, 
 its left peduncle ; m, m, nates ; m! m', testes ; n, corpus genioulatum internum ; o, o, 
 superior peduncles of cerebellum ; p, valve of Vieussens ; q t 4th nerve ; r, 3d ventricle ; 
 s, s, anterior superior, and (, t, posterior superior lobes of corcbellum ; u, upper surface 
 of vermiform process." 
 
 base of the right hemisphere is seen on figure 13 (TJi). The 
 relation of these two principal ganglia at the base of the brain 
 will best appear by reference to fig. 1 1 (a and b), which also 
 
»•] STRUCTURE OF THE BRAIN. 
 
 33 
 
 shows the surface of the cerebellum, or little brain, in the rear. 
 These two large bodies, an anterior and posterior in each hemi- 
 sphere, are masses of nerve fibre, encompassed with grey 
 matter, and are known as the basal ganglia, the anterior being 
 largely made up of motor nerves, the posterior mainly of 
 sensory nerves. In the centre (between the optic thalami) are 
 four smaller basal ganglia (corpora quadrigemina, m, m, m! , ml'), 
 which are composed of both grey and white matter. These 
 four bodies are connected both with the cerebellum and 
 with the optic thalamus, and are in close relation with the 
 optic nerve. 
 
 If now the organ be turned with its lower surface upwards, 
 we have a view of the base of the brain, with its con- 
 volutions (fig. 12) ; and at the same time, the lower sur- 
 face of the cerebellum, of the bridge, and of the medulla, 
 along with the origin of the leading cranial nerves. Im- 
 mediately underneath the brain proper, and situated quite to 
 the rear of its base, is the little brain, named the cerebellum. 
 Its upper surface is represented on fig. 11, its under on fig. 12. 
 It is held by two bands in close connection with the brain 
 proper. In many features of structure it closely resembles 
 the brain proper, for though smaller in size, it has its two 
 hemispheres — its mass of grey matter, and its body of white 
 matter or aggregate of nerve fibres. Notwithstanding these 
 general marks of resemblance, however, it differs considerably 
 in aspect from the brain proper. It is distinguished outwardly 
 by its laminated appearance, as if lines had been drawn across 
 its surface. This is consequent upon the fact that the grey 
 matter is laid down in very thin plates, into the most of which, 
 however, the white matter runs as in the convolutions of the 
 brain proper. "When a section is made through the cerebellum, 
 it presents an appearance as of the branches and foliage of a 
 tree, which has led to the application to it of the fanciful name 
 arbor vitae, — tree of life. In the white matter are numerous 
 fibres which connect the cerebellum with other portions of the 
 nerve centre above and below, while other fibres pass through 
 the bridge, and connect together correlated regions in the two 
 hemispheres of the cerebellum. 
 
 c 
 
34 
 
 THE RELA TIONS OF MIND AND BRAIN. [chap. 
 
 Fig. 12.— LOWER SURFACE OF THE BRAIN AND SUBORDINATE NERVE CENTRES. 
 (From Turner's Anatomy.) 
 
 "Diagram of the base of the brain with its arteries. I. to IX. cranial nerves ; Fr, frontal 
 lobe ; T3, temporo-sphenoidal lobe ; Oc, occipital lobe ; 1, great longitudinal fissure ; 2, 
 Sylvian fissure ; 6, flocculus ; 7, tonsil ; 8, postero-inferior ; 9, slender ; 10, biventral 
 lobes of cerebellum ; 11, left anterior pyramid ; 12, right olivary body ; 13, decussation of 
 the pyramids ; 14, left anterior perforated space ; 15, tuber cinereum and infundibulum ; 
 16, 16, corpora albicantia." 
 
 The remaining portions of the great nerve centre will be best 
 described by reference to figure 1 3, which illustrates their con- 
 nection with the brain above, and at the same time shows the 
 origin of the chief cranial nerves. 
 
 In the upper portion of fig. 13, certain parts of the brain 
 itself are shown. On the left, the convoluted part is the con- 
 cealed central lobe, known as the Island of Eeil. On the 
 right is the inner and lower of the two basal ganglia, that 
 
II.] 
 
 STRUCTURE OF THE BRAIN. 
 
 35 
 
 d ca 
 
 Fig. 13.— THE LOWER DIVISIONS OP THE NERVE CENTRE AS CONNECTED 
 WITH THE BRAIN. 
 
 (From Quain's Anatomy.) 
 
 " On the right side the convolutions of the central lobe or island of Reil have been left, 
 together with a small part of the anterior cerebral convolutions : on the left side these 
 have been removed by an incision carried between the thalamus opticus and the cerebral 
 hemisphere. 
 
 1', the olfactory tract cut short and lying in its groove between two convolutions ; II, the 
 left optic nerve in front of the commissure ; II', the right optic tract ; Th, the cut surface 
 of the left thalamus opticus ; C, the central lobe or island of Reil ; Sy, fissure of Sylvius ; 
 X X, locus perforatus anterior ; e, the external, and i, the internal corpus geniculatum ;. 
 h, the hypophysis cerebri or pituitary body ; tc, tuber cinereum with the infundibulum ; 
 a, one of the corpora albicantia ; P, the cerebral peduncle or cms ; /, the fillet ; III, close 
 to the left oculo-motor nerve ; X , the locus perforatus posticus ; PV, pons Varolii ; V, 
 
5 THE RELA 770NS OF MIND AND BRAIN. [chap. 
 
 nown as the optic thalamus. Just below these, and diverging 
 5 the left and to the right, are the cerebral peduncles {crura 
 irebri), which are the bands of nerve fibres which connect the 
 rain proper with the bridge, medulla, and spinal marrow, 
 ust underneath these, in one solid mass, with transverse 
 ines, is the bridge {pons Varolii). Immediately under this 
 re four elongated bodies, two lying closely together next the 
 liddle of the organ, and two, more oval in shape, outflanking 
 be middle pair. These four, together with other four behind, 
 onstitute the lowest division of the encephalon, the united 
 aass being known as the medulla oblongata. To the left of the 
 'ridge and medulla is seen some tracing of the cerebellum, 
 /hich considerably outstretches the two lower divisions of the 
 ncephalon. 
 
 The bridge is in close connection with the hemispheres both 
 f the little brain and of the brain proper. In the bridge there 
 3 a combination of grey and white matter. The grey matter 
 3 distributed through the substance. Many longitudinal fibres 
 un up through the bridge, from the medulla oblongata to 
 tie crura cerebri, and brain proper. Others pass transversely 
 hrough it from one hemisphere of the cerebellum to the other, 
 onnecting them together. Thus the bridge is a pathway 
 y which strands of communication pass between different 
 ivisions of the encephalon, and it serves as a bond of union 
 iving compactness or solidarity to the entire organ. 
 
 The lowest portion of the encephalon (medulla oblongata) 
 3 an oblong body, about an inch and a quarter in length. It 
 ies immediately below the bridge, and on the summit of the 
 pine, so as to constitute the grand starting-point of the spinal 
 ord. It is divided into two halves, each of which consists 
 
 the greater root of the fifth nerve ; +, the lesser or motor root ; on the right side this + 
 is placed on the Gasserian ganglion, and points to the lesser root, where it proceeds to 
 join the inferior maxillary nerve ; 1, ophthalmic division of the fifth nerve ; 2, superior 
 maxillary division ; 3, inferior maxillary division ; VI, the sixth nerve ; VII a, the facial ; 
 VII 6, the auditory nerve ; VIII, the pneumo-gustric nerve ; VIII o, the glosso- 
 pharyngeal ; VIII b, the spinal accessory nerve ; IX, the hypoglossal nerve : fl, the 
 flocculus ; fh, the horizontal Assure of the cerebellum (Ce) ; am, the amygdala ; p a, the 
 anterior pyramid ; o, the olivary body ; r, the restiform body ; d, the anterior median 
 fissure of the spinal cord, above which the decussation of the pyramids is represented ; 
 c a, the anterior column ; o I, the lateral column of tho spinal cord ; CI, the suboccipital 
 or first cervical nerve." 
 
«• ] STRUCTURE OF THE BRAIN. 37 
 
 of four bodies. Two of these are shown on the figure, the 
 anterior pyramids and the olivary bodies. Behind are the 
 restiform bodies and posterior pyramids. The medulla oblon- 
 gata is composed both of grey and white matter, after the 
 manner of the superior portions of the nerve centre, and this 
 holds good also for the spinal cord. The grey matter is distri- 
 buted through the substance of the medulla. The white matter 
 is arranged in bands or columns, of which, as we have seen, 
 there are four pairs. These elongated bands of nerve fibre pass 
 down from the medulla oblongata to the spinal cord. Some 
 of these bands of fibre cross from the one side of the spinal 
 cord to the other at the foot of the medulla, this crossing being 
 known as the decussation of the fibres. 
 
 I shall only briefly refer to the provision for the nourishment 
 of the great nerve centre. The arteries carrying the supplies of 
 fresh blood pass up to the base of the brain. Some of these 
 blood-vessels enter the interior of the organ to supply the 
 ganglia at the base, and the white matter in the core. Others 
 pass upwards by the outside of each hemisphere for the supply 
 of the grey matter of the brain. These arteries sub-divide 
 into numerous ramifications, carried in all directions on the 
 delicate pia mater which descends into all the furrows between 
 the convolutions. In this way, the fresh blood is constantly 
 being carried over the entire mass of grey matter, and is let 
 down into every little corner of its folds, where it is distributed 
 by hair-like canals. A much larger portion of the blood for the 
 brain goes to the grey or cellular matter than to the white 
 or fibrous. It is reckoned that five times as much is con- 
 stantly being supplied for the nourishment of the nerve cells 
 as is provided for the nourishment of the nerve fibres. 1 This 
 implies five times more demand in the one case than in the 
 other,— five times more waste to be repaired. Along with 
 this contrast, we have another, brought out by comparison of 
 the brain with the body as a whole. We have seen 2 that 
 the weight of the whole nerve centre, including all its parts 
 in comparison with the weight of the entire body, is about 
 
 1 Turner's Anatomy, vol. i. p. 284. 
 
 2 Quain's Anatomy, vol. ii. p. 570. 
 
38 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 1 to 36, or 1 to 40. Now, according to the estimate of Haller, 1 
 one-fifth part of the whole blood-supply goes to the brain. 
 In this we have a basis for estimating the importance of the 
 organ, and the amount of activity involved in its ordinary 
 exercise. 
 
 1 Elem.enta Physiologim. 
 
'"•] THE NERVE SYSTEM. 
 
 39 
 
 CHAPTEK III. 
 
 THE NERVE SYSTEM AS DEPENDENT ON THE GREAT NERVE CENTRE. 
 
 In the preceding chapter attention has been directed to the 
 bands or columns of nerve fibres which enter into the constitu- 
 tion of the medulla oblongata. These fibres are continued into 
 the spinal marrow, which gives origin to the greater number 
 of the nerves which are distributed to the skin and muscles. 
 
 Before describing the spinal marrow, and its nerves, how- 
 ever, it should be stated that the great nerve centre within the 
 head gives origin to several nerves, most of which are connected 
 with the face and head, and known as the Cranial Nerves. Con- 
 spicuous among these are the nerves of special sense, — sight, 
 hearing, smell, and taste. Along with these are the nerves 
 which regulate the movements of the organs of vision; and 
 others which control the manifold movements of the muscles 
 of the face, thereby determining expression. Eelatively to the 
 surface occupied, a larger proportion of nerves is assigned to 
 the face than" to any other portion of the body. All these 
 lines of nerves, while they are of the greatest importance, and 
 most nearly related to the nerve-centres, are necessarily of 
 limited extent. Their roots in the brain and their terminal- 
 organs are in close proximity. Others of the cranial nerves are 
 associated with the movements of the tongue, with swallowing, 
 with movements of the heart, and with the functions of respira- 
 tion. Passing by these meanwhile, I shall in the first instance 
 trace the distribution of the nerve system over the body. 
 
 The spinal marrow, elongated in form, lies in the spinal 
 canal within the backbone, where it is enclosed by three mem- 
 branes such as cover the brain. In harmony with the bilateral 
 arrangement seen everywhere in the nerve centre, the spinal 
 marrow is arranged in two halves, and terminates below in a 
 pointed extremity. We cannot, indeed, speak of hemispheres, 
 but there are still two halves, marked out by a clearly defined 
 
40 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 fissure ia front, and by another behind. These fissures separate 
 the spinal cord superficially into two sides, which, as in the 
 brain, are connected by transverse commissural fibres to main- 
 tain the unity of the organ. Here also we have both the grey 
 matter, with its supply of nerve cells and nerve glue, and the 
 white or fibrous substance. But the positions of the white 
 and grey are reversed. The white or fibrous matter is here 
 the external, lying nearest the walls of the spine. The grey 
 matter is surrounded by the white, and is not equally dis- 
 tributed. It is at some points more abundant than at others. 
 With its supply of blood-vessels and connecting fibres, it is so 
 arranged as to spread out as with horns curving towards the 
 places where the nerve fibres make their exit from the spinal 
 cord. This will appear from the following figure (14). 
 
 The white matter is arranged in columns, and from each half 
 
 of the cord nerves arise 
 which pass out of the 
 spinal canal at the ver- 
 tebrae. In this way 
 there are in all thirty- 
 one pairs of nerves sent 
 out, taking distinct courses 
 throughout the body. 
 These are known as the 
 Spinal Nerves, in contrast 
 with the cranial nerves. 
 
 Fig. K— SECTION OF THE SPINAL CORD, "pv ^ nT1A n f +l, a „;„„l 
 SHOWING THE RELATION OF THE WHITE ■ L " xvl1 {JaG oi lui > Spinal 
 
 and grey matter. nerves springs from two 
 
 (From Turner's Anatomy.) , r00 t S) anterior and pOSte- 
 
 " Transverse section through the spinal cord. AF, r j OT . f)_ r u„ ^.i.^.. 
 
 antero-median, and PF, postero-median Assures; . .' . . lae P obl;erlor 
 
 PC, posterior, LC, lateral, and AC, anterior columns; division, JUSt after it has 
 
 AR, anterior, and PR, posterior nerve ;roots; C, • „„ j ±- + r • i 
 
 central canal of cord, with its columnar epithelial lssuea Irora ^V Spmal 
 
 lining. The pia mater is shown investing the cord, canal, there is a ganglion 
 
 sending processes into the anterior and posterior ■■ at ° i 
 
 fissures, as well as delicate prolongations into the 0r enlargement, thrOUgh 
 
 columns. The creseentic arrangement of the grey which the nei'Ve DaSSeS 
 
 matter is shown by the darker-shaded portion." _ r ' 
 
 There is no such ganglion 
 on the anterior division. Just beyond this ganglion, the two 
 roots form into one, constituting a spinal nerve trunk. After 
 the roots have been thus united the ramification of the nerves 
 
in.] THE NERVE SYSTEM. 41 
 
 takes place. This is effected, first, by the nerve trunk dividing 
 into two parts, the one passing off to the rear of the body, the 
 other to the front. These are not a mere reappearance of the 
 two branches issuing from the spinal canal. Each division 
 contains a portion of the fibres of each of the two roots which 
 come from the spinal cord. These two roots, as we shall see, 
 have distinct functions, the rear line being nerves of sensation ; 
 the front, motor nerves. A share of both finds its way into each 
 ramification. The fibres in each division have different areas 
 of distribution. The one set (motor) pierces into the interior 
 of the muscles ; the other set (sensory) takes its course so as 
 to end in the skin. 
 
 Attention should now be. directed to the distribution of the 
 fibres. The one set (motor) while penetrating into the sub- 
 stance of the muscle, has the nerve strand divided, and again 
 subdivided, as one part after another of the tissue is reached. 
 This process of subdivision proceeds so far, that at last even 
 the single fibre itself divides. As to the termination of this 
 very delicate process, there seems to be diversity of opinion. 
 Some maintain that it ends in a very fine network ; others 
 that it ends in a more compact plate, situated within the 
 muscular fibre. In the manner now described, the muscle is 
 taken possession of, and is thus placed in vital connection 
 with the nerve centre. The divisions and subdivisions found 
 in a single muscle do not constitute isolated lines of com- 
 munication. By a series of connecting fibres they are bound 
 together, so as to constitute a network of controlling fibres, 
 known as a nerve plexus. In this way the nerve fibres in a 
 muscle constitute a unity, and all parts of the muscle move 
 together as by the strain upon a single cord. This unifying 
 process becomes more complex according to complexity of mus- 
 cular arrangement. The nerve strand .for a special muscle or 
 order of muscles is connected with other strands farther up 
 the system ; and thus, in order to secure co-ordination or 
 symmetrical movement of the several parts of the limbs, the 
 arrangements of the nerve-plexus become more complicated. 
 
 The other set of nerves (sensory) take an outward course. 
 The fibres of this order find their way to the surface of the 
 body, where they are distributed to the papillae of the skin, ■ 
 
\2 THE RELA TIONS OF MIND AND BRAIN. [chap. 
 
 yhere each fibre terminates in a kind of expansion or bulging, 
 [n this way the termination is sensitive to external influence, 
 )ven the slightest impact. This terminal expansion is known 
 is an end-bulb, or touch organ. Some sensory nerves pass to the 
 nucous membranes, where they often end in bulbs, sometimes 
 dmply in a pointed fibre ; but at other times, the nerve twists 
 ■ound and forms a coil. Besides these varieties of terminal 
 brm, there are, towards the extremities of some of the sensory 
 lerves, sets of small granular bodies, visible to the naked eye 
 corpuscles of Pacini). These are gathered around the nerve 
 ibres which pass to the more sensitive parts of the body, such 
 is the fingers, toes, arm, and neck. The following illustration 
 fig. 1 5) indicates their appearance. 
 
 These corpuscles are most numerous towards the extremity 
 )f the nerve, as illustrated in No. 1 of the figure. When greatly 
 nagnified, as in No. 2, the corpuscle is found to have a stalk, 
 vith a nerve-fibre passing up through the centre of the 
 mlarged body. When inside this body, the minute fibre loses 
 ts usual sheath, and is surrounded by layers of connective 
 issue, within "which is a gathering of transparent protoplasm. 
 These corpuscles probably increase the sensitiveness which 
 >therwise belongs to the sensory nerve. 
 
 From the general description given in this outline, it will be 
 ;een that the nerve system, so far as it is here under observa- 
 ion, consists of two distinct lines of communication. Thesa 
 lave been universally recognised since Sir Charles Bell laid 
 be results of his researches before the Royal Society in 1834. 1 
 There is one order of nerves essentially related to the muscular 
 lystem, its extreme ramifications being all lodged within the 
 nuscles. This order uniformly issues from the front of the 
 ipinal marrow. This anterior division is indeed afterwards 
 sombined with the posterior (sensory), but only to be thereafter 
 listributed in combination for the several parts of the body. 
 Chere is no confusion of the two orders. The lines which 
 ire completely distinguished as they pass out from the spinal 
 jord, continue distinct throughout. On account of the direc- 
 ion taken by the nerves distributed to the muscular system, 
 md the function which they fulfil, they are called not only 
 1 The Nervous System of the Human Body. 
 
III.] 
 
 THE NERVE SYSTEM. 
 
 43 
 
 motor nerves, but efferent or out-carrying nerves, and sometimes 
 centrifugal. As nerves of motion, it is their function to carry 
 
 Magnified + 350. 
 
 Via. 15.— CORPUSCLES FOUND ON SENSORY NERVES AT THE MORE SENSITIVE 
 
 PARTS OF THE BODY. 
 
 (From Turner's Anatomy, after Kolliker.) 
 
 " 1. Nerves of one linger with the Pacinian corpuscles attached ; 2. a Pacinian corpuscle X 350 ; 
 
 a, stalk or peduncle ; b, nerve fibre in stalk ; c, external layers of capsule ; d, inner layers ; e, 
 
 non-medullated nerve fibre in the central core ; /, branching of terminal end of nerve fibre. " 
 
4+ THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 impulses from the centre so as to move the muscles with which 
 they are severally connected. 
 
 The other set of nerves, which issues from the back of 
 the spinal cord, may, as naturally as the former, be said to go 
 out from the centre to the surface of the body. But, in view of 
 their function, which is to carry impressions from the surface 
 to the centre, they are named not only sensory nerves, but also 
 afferent or in-carrying, nerves, — that is, nerves which, as soon 
 as an impression is made upon them, carry that impression 
 upwards in the direction of the centre. These are also named 
 centripetal. 
 
 "We have thus two entirely distinct arrangements in the 
 nervous system. By one branch, nerve influence is carried 
 from above downwards ; by another branch, nerve influence is 
 carried from below upwards. The one accomplishes muscular 
 movements ; the other transmits sensory impressions. Fibres 
 of these two distinct orders run alongside each other, and are 
 even wonderfully interlaced, but there is no functional disturb- 
 ance. The conducting line or axial cylinder of each nerve 
 fibre being surrounded by medullary matter, and enclosed 
 within a membrane, is kept in isolation for transmission of a 
 distinct message. 
 
 Though the two orders of nerve fibre are distinct in function, 
 they are alike distinguished by excitability, and nothing is 
 known concerning their action which seems to warrant the 
 supposition that there is any difference in the nature of the 
 nerve lines, or of the influence under which they come into 
 play, or of the molecular change consequent upon their use. 
 The only recognised difference between the nerve lines is found 
 in the mode of distribution. The condition of vital, activity is 
 the same for both, — discharge of nerve energy from the grey 
 or cellular matter. The marked difference of action depends, 
 in the case of the motor nerves, upon impulse from the brain 
 centre along the line ; in the case of the sensory nerves upon 
 impression made on their peculiar terminal structure. But in 
 both cases, vital connection with the store of nerve energy in 
 the grey matter is needful, in order that the excitability of 
 the nerve fibre may be maintained. 
 
 Keeping in view the common features of the two sets of 
 
in.] THE NERVE SYSTEM. 45 
 
 nerves, we may next treat more especially of the distinctive 
 function assigned to each. 
 
 One division of the nerves regulates all movements of the 
 muscles. These motor nerves are so connected as not merely 
 to provide for separate action of distinct parts of the body, such 
 as an arm or a finger, but also for co-ordinated action of several 
 parts for a single end, as in walking or leaping. On account 
 of the muscular system being acted upon by impulses trans- 
 mitted from the centre, and for a definite purpose, the muscle 
 so moved has been named " a voluntary muscle," in contrast with 
 " involuntary muscles," such as in the heart or stomach, which 
 move independently of the will. In the same way, the nerves 
 which produce muscular movement, such as the motion of the 
 hand in writing, are sometimes spoken of as voluntary nerves. 
 This is a figurative use of the term voluntary or volitional, 
 which can hardly be misunderstood. Neither the muscles nor 
 the nerves are voluntary, but these two are the " instruments 
 of volition," to use the phrase of Sir Charles Bell. Yet there 
 may be need to guard against the risk of misapprehension here. 
 And this is most effectually done by remarking that the so- 
 called " voluntary " nerves and muscles may act involuntarily, 
 as in the case of " reflex actions," that is, actions which are the 
 result of sensory stimulus without consciousness. Besides, 
 it must be remarked that this use of the word " voluntary " or 
 " volitional " is already a draft on the department of experience. 
 Neither anatomical nor physiological observation accounts for 
 the use of the term. The only thing which we are at this 
 point warranted to affirm as bearing on the action of motor 
 nerves and muscles, is that they are moved by impulses pro- 
 ceeding from the nerve centre. 
 
 The other division of nerves is distinguished by special 
 susceptibility at the extremity to impression from without. 
 All the neryes of this division carry the impression from the 
 extremity of the line to the nerve centre. In this way, even 
 changes of temperature influence the body, and the slightest 
 touch of a finger gives occasion for a message to the terminus. 
 It thus appears that functional activity in this case depends 
 upon susceptibility of the terminal part of the nerve to touch. 
 If the external object, after touching, remain in contact, there 
 
46 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 is not a continuous communication. The sense of contact is 
 gradually lost, and is not clearly restored except by movement 
 of the object, or movement of the part in contact with it. If 
 strong pressure be applied to the terminal region, the suscepti- 
 bility of the nerve is for the time suspended. A prior freedom 
 from pressure is needful at the point of contact in order that 
 functional activity may take place at the moment of contact. 
 
 Besides this sensori-motor system now described, there is a 
 distinct order of nerves connected with the lungs, stomach, and 
 other viscera. This is an order not in the same way connected 
 with our experience, and not under our control. I shall not 
 occupy space with detailed description. It is known as the 
 sympathetic system. As a system, it is closely connected 
 with the cerebro-spinal system, for the two are bound together 
 by connecting fibres. The main part of the Sympathetic 
 System consists of two gangliated cords, which run down 
 outside of the spinal column, one on each side of it. From 
 these cords the fibres are extended to the different organs 
 already indicated. 
 
 The two divisions of nerves belonging to the cerebro-spinal 
 system, the sensory and the motor, have their common meeting- 
 place in the grey matter of some portion of the nerve centre. 
 This holds true for all the nerves, whether they ascend as far 
 as the brain itself, or terminate at some earlier point. As we 
 have seen, the grey matter is found not merely in the brain 
 proper, including the basal ganglia, but also in the subordinate 
 divisions of the centre, and in the spinal cord. Its primary 
 functions are determined by its situation and its structure. 
 As to its situation, it is the essential feature of every division 
 of the nerve centre ; as to its structure, it is entirely dis- 
 tinguished from the nerve fibres accumulated within the 
 centres. 
 
 Taking first the structure of the tissue, we have under 
 review a complete contrast with the white matter. Wherever 
 the grey matter is found, its essential structure is the same. 
 Its masses are storehouses of nerve cells packed in nerve glue. 
 In these nerve-cells nerve-energy is generated and stored; 
 and provision for continual reproduction of this energy is made 
 by the large blood-supply which is pumped up to the cranial 
 
"1-1 THE NERVE SYSTEM, 
 
 47 
 
 region by night and by day, in sleeping hours and in waking. 
 The whole nerve system, down to its most remote extremities, 
 is kept in readiness for action only by continual storing of 
 nerve energy in these cellular regions. On this point there is 
 perfect agreement among physiologists. 
 
 Glancing next at the situation of the grey matter, we per- 
 ceive the distinctive feature of a nerve centre. While the 
 nerves spread outwards, the grey matter is massed here. In 
 this way, the spinal cord itself must be regarded as a part of 
 the nerve centre. In strict accordance with this characteristic, 
 investigations have shown that it operates as a centre of reflex 
 action. And, in so far as we mark separately organised masses 
 of grey matter in the medulla, bridge, cerebellum, and brain 
 proper, we recognise those bodies as distinguishable portions 
 of the great central arrangement of the nervous system. 
 
 Taking now together the central organs and the communi- 
 cating fibres, we have to contemplate the whole as one system. 
 And here it is needful to dwell on the conditions of functional 
 activity of the system, additional to vital connection with the 
 stores of nerve energy. The nerves of sensibility depend for 
 exercise upon excitement of the nerve at its peripheral termina- 
 tion. The effect of the impression made on a sensory nerve is 
 carried along the whole line to the nerve centre. Questions 
 concerning the experience consequent upon such transmission 
 are reserved for a later stage of inquiry. Here I speak only of 
 excitability of nerve fibre. When we turn to the other set of 
 fibres, the motor nerves, the question as to the additional condi- 
 tions of their exercise is more difficult. These fibres are acted 
 upon from within,. and action at the centre cannot be observed 
 as we notice influence exerted on the surface of the body. Here 
 we are practically without observations, and this state of things 
 must continue. The normal action of the grey matter does not 
 even come within the range of personal experience, and we 
 _are also shut out from that avenue of knowledge. Whether 
 different portions of the grey matter may have different 
 functions, one part receiving sensory impressions, another dis- 
 charging motor stimulus, or whether these functions are com- 
 bined in the several parts, it is impossible to say with certainty. 
 Some light will be thrown on the perplexities of this question 
 
48 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 when reference is made to the results of electric stimulation of 
 the grey matter. Even the most minute researches into the 
 structure of the brain do not warrant us to say that some cells 
 are merely receptive, others active or efficient in the produc- 
 tion of movement along certain fibres. The nerve cells do 
 indeed vary in size, and they occupy different positions, but their 
 common features are such as to lead to the inference that they 
 have common functions, and that they are equally sources of 
 activity. And in this connection it needs to be remarked 
 that the excitability which is common to both sets of nerve 
 fibres implies movement. Transmission of impression in- 
 volves vibration as well as tension and relaxation of the motor 
 nerves. In this sense we may say that all cells exert motor 
 influence, thereby granting that the grey matter has the double 
 function of receptivity and activity. I say the double func- 
 tion, for, if it be admitted that there are sensory cells, and 
 that these induce a form of activity, it will be granted also, 
 in view of the familiar facts of reflex action, that the motor 
 cells are receptive. In reflex action, sensory impression is the 
 occasion of movement, without our being conscious of influence 
 exerted upon us, or of influence being exerted by us. If we 
 allow separate cells for the distinct effects, we grant that there 
 is a sensory cell, which is receptive, and at the same time 
 active in being receptive ; and we also grant that there is a 
 motor cell which is receptive of impulse transmitted from a 
 sensory cell, in order that it may be active. There may 
 indeed be several cells at each point influenced, but the 
 conditions of functional activity remain the same. Voluntary 
 movement raises a distinct problem. 
 
 From the considerations now adduced bearing on the action 
 of sensory and motor nerves, with that of their correlated cells, 
 we are led to the conclusion that the stores of nerve energy in 
 the grey matter of the brain need some agency to operate upon 
 them in order that the energy may be liberated for actual 
 work. During the period of inaction, the vital connection 
 subsisting between the storehouse of nerve energy in the brain 
 and the lines of communication spread over the body, keeps up 
 the excitability of the nerve lines, by reason of which they are 
 sensitive to impression. The state of sleep, involving cessation 
 
ill,] THE NERVE SYSTEM. 49 
 
 from effort with continued coursing of blood-supply through the 
 brain, provides against exhaustion, which would arise from 
 constant working. But in the active state a force beyond the 
 store of nerve energy must operate in order to liberate some 
 portion of that energy, thus bringing into action one or more of 
 the connected fibres. Some impact must occur at the surface 
 of the body, in order to act upon the excitability of the 
 sensory nerve. Some power must be exerted at the centre, 
 in order to bring into exercise a motor nerve. The relation 
 established between sensory and motor cells is such that 
 a single influence exerted from without may operate first 
 on the sensory nerve, and next through it upon the motor. 
 This is the case in reflex action. A similar circle may be com- 
 pleted under influence from within the organism, as for example 
 under the power of physical appetite, such as hunger. Imme- 
 diately beyond this arises the interesting question, most diffi- 
 cult to answer, whether the movements of animals can be all 
 included within the class of sensori-motor or automatic actions. 
 Beyond this again is the still more interesting question, — more 
 directly connected with my present inquiry, — what variety of 
 agents is found to operate in human life causing the use of the 
 motor nerves. For an answer to this question we must travel 
 beyond the bounds of the present department of inquiry, pass- 
 ing into the region of personal experience, into which we shall 
 advance hereafter. Meanwhile, having remarked that some 
 impulse beyond the nerve energy itself is required to bring it 
 into action, it is clear that only some forms of human action, 
 or parts of action, come directly under external observation. 
 If "voluntary" or "volitional" activity exist as a distinct 
 form of human action, it is not discovered by physiological 
 science. Whatever views we may be disposed to entertain 
 concerning the possibility or impossibility of voluntary action 
 on the part of the lower animals, these views cannot well be 
 regarded as more than hypothetical. While, so far as human 
 activity is concerned, there are two alternatives before us : if 
 all human action is dependent on prior sensibility, it may all 
 be explained by external factors ; if it cannot be thus explained, 
 there is some other force at work than the nerve force which 
 operates upon the sensory and motor nerves. 
 
 D 
 
;o THE RELA TIONS OF MIND AND BRAIN. [chap. 
 
 Beserving the perplexities of this question for a later 
 stage, we have further to consider here the molecular changes 
 ivhich occur in the grey matter, consequent on activity of 
 ;he nerve system. When a demand is made on the stores of 
 lerve energy hy the exercise of either a sensory or a motor 
 nerve, there are certain molecular changes as the direct result, 
 fn the nerve centre these changes are the expression of what is 
 otherwise expressed in the external sphere. The force exerted 
 means energy liberated and discharged, involving loss or waste 
 in the organ which generates that energy. As a consequence, 
 bhere is a demand for restoration of energy by nutrition. To 
 3ome extent the molecular changes in the human brain have 
 been matter of observation. There are cases on record in 
 which, by accident, or amongst the disasters attendant on war, 
 part of the cranium has been carried away, and some part of 
 the brain exposed. In such cases, the pallor of the brain with 
 exhaustion, such as, in extreme cases, may be seen on the 
 countenance, and the flushing of the grey matter with fresh 
 blood-supply after a meal, were clearly seen. Further, the 
 whole series of experiments on the brain of living animals 
 under anaesthetics, afterwards to be considered, has made us 
 familiar with the exhaustion which soon follows upon action, 
 and which soon renders discontinuance of the experiment 
 needful. It is, therefore, one of the clearly ascertained results 
 in physiology, that molecular changes in the brain are conse- 
 quent upon impulses propagated along the strands of nerve 
 fibres. The grey matter has it as its primary function to 
 evolve nerve energy, and that is drawn upon by every form 
 of nerve action. This applies wherever the grey matter is 
 found. Accordingly the law will apply equally to the brain 
 proper, the little brain, the bridge, the medulla, and the spinal 
 cord. Experimental evidence amply confirms this position. 
 
 A further question there is, as to the degree of exhaustion 
 which may occur at the nerve centre under the activity of the 
 nerve system. Exhaustion will be proportionate to exercise. 
 The more intense the labour, the sooner we must have the 
 sense of waning force. I say nothing here as to the difference 
 between mechanical and intellectual labour. However familiar 
 the work done may be to the worker, the time soon comes 
 
in.] THE NERVE SYSTEM. 51 
 
 when there must be a cessation from activity. Hence the need 
 not only for nourishment, but also for repose in sleep, when 
 demand is abated, while the nourishing process is continued 
 with what may be stated as redoubled power. 
 
 Having thus spoken of the primary function of the nerve 
 centre as that of providing nerve force, may we further speak of 
 the grey matter as itself distinguished by sensibility ? If it be 
 the centre to which sensory impressions are carried, is the brain 
 itself to be regarded as a sensitive organ ? A large number 
 of surgical operations carry a distinct answer to this question. 
 Protruding parts of the brain have been cut away without any 
 sense of pain, and without the appearance of the loss having 
 caused any disturbance to mental action. " Whole masses of 
 brain may be destroyed by disease, or actually removed, with 
 impunity; that is, without any immediate influence on the mind, 
 or on the power of motion or of sensibility." 1 What is known 
 as " the American crow-bar case " is one of the best and most 
 familiar examples on record. 2 I give the narrative in con- 
 densed form as presented by Dr. Ferrier. " Through an acci- 
 dent in blasting a rock, a young man was hit by a bar of iron, 
 which, entering at the left angle of the jaw, passed clean 
 through the top of his head in the left frontal region, having 
 traversed the anterior part of the left hemisphere. This man 
 speedily recovered, and lived for thirteen years afterwards 
 without manifesting any special symptoms which could be 
 attributed to such a serious injury to the brain." 3 These 
 quotations really throw light on the deeper question of the 
 relation of integrity of brain substance to normal activity of 
 mind, but I am content meanwhile to use them as illustrations 
 supporting the position that there is not the intense sensitive- 
 ness in the grey matter of the brain which might have been 
 expected in view of the fact that it is the great centre of 
 sensory impressions. Great sensibility to impression there is 
 at the periphery; whenever that sensibility is affected there 
 is immediately transmission of a message to the brain, but 
 
 1 Sir Charles Bell's Nervous System, p, 208. 
 
 a Reported by Dr. Bigelow, American Journal of the Medical Sciences, 
 July 1850. 
 
 3 Functions, p. 126. 
 
'. THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 icts do not warrant the supposition that the message is 
 elivered at the central organ by a simple repetition of what 
 as occurred at the extremity of the nerve line. The 
 sat of sensibility is recognised by us as the finger, toe, 
 r arm, as the case may be, but this is not the result of 
 msibility at the centre being correlated with sensibility at the 
 nger, toe, or arm. That there is transmission of influence is 
 eyond doubt. If a nerve fibre be cut at any point in its 
 Durse, there is temporary insensibility at the point from 
 r hieh the fibre comes, or temporary loss of motor power, as 
 le case may be. In course of time, the severed parts may 
 e reunited, 1 and the power of communication restored. The 
 ecessity for integrity of communication is thus manifest. But 
 tcts are against the supposition that the message is delivered 
 y acting upon a sensitive surface in the grey matter. There 
 i action upon the nerve cells, and consequent molecular change, 
 ut there is not sensibility in the grey matter as there is in 
 le white or fibrous. This conclusion as to non-sensibility is 
 ivoured by the similarity of the cells in the grey matter, in 
 armony with the depth of the layer in which they are found. 
 Here it becomes possible to indicate certain general 
 haracteristics of nerve action. We have a graduated series 
 I nerve centres, charged with nerve energy, and constantly 
 laintaining in a state of vital activity the whole extent 
 f the nerve system, with its sensory and motor nerves, 
 hese centres and lines of communication are formed in the 
 mbryo, — they exist in the infant, — they are exercised by the 
 hild in the earlier and simpler stages of action belonging to 
 rem, — and in mature life they operate with certain advantages 
 squired in accordance with the laws of normal exercise, 
 hese laws, so far as yet clearly recognised, are mainly con- 
 3rned with the action of the nerve fibres, for we are still igno- 
 mt in great degree of the laws which regulate the action of 
 le convolutions of the brain and grey masses of the subordi- 
 ate centres. At this point we make account mainly of these 
 ivo characteristics: excitability of both orders of the nerve 
 nes, and equal dependence of both on the nerve energy stored 
 1 the grey matter. Along with these characteristics, we must 
 1 Carpenter's Principles of Human Physiology, seventh ed., p. 506. 
 
ni.] THE NERVE SYSTEM. 53 
 
 draw to some extent on the facts of personal experience, leaving 
 detailed analysis of, this experience for a later stage. On this 
 region of experience I draw meanwhile only so far as to remark 
 that we have some personal power to determine what nerve 
 lines, sensory and motor, shall be brought into use. Nerve 
 force will indeed operate as the result of slight impression 
 from an external object, and, consequent upon this, further 
 operation of nerve force will be manifested in the action of 
 motor nerves, thus giving rise to reflex action. To this extent 
 it holds true that nerve force may be liberated by influence 
 from without. In this way, and by action of vital organs 
 within, certain nerve tracts are kept in regular use. But we 
 know in personal experience that by our own determination 
 both sensory and motor tracts may be brought into play. 
 Besides the spontaneous use, there may be a voluntary use of 
 nerve energy. I make here no further attempt to define this 
 voluntary use than by remarking that it is not spontaneous 
 response to external influence, and not the result of functional 
 activity of other organs distinct from the brain. Now, there are 
 some laws of nerve action which come into view only in connec- 
 tion with this voluntary or personal direction of nerve energy. 
 
 The most general aspect of the law of exercise may be stated 
 thus : Frequency of use gives increased, conductivity. Muller, 
 when treating of "voluntary movements," incidentally states 
 the fact thus: "the conducting power of the nervous fibres 
 increases with the frequency of their excitement." 1 This 
 general statement, in the first instance, merely indicates what . 
 is familiar to us in the use of our faculties, that use leads to 
 growth of power. This holds true of the muscular system, and, 
 as muscular action is dependent on nerve action, what is now 
 remarked is only the extension of the same law to the higher 
 controlling power. But the law wears a different aspect when 
 applied to the nerve system. It does not imply that a nerve 
 line becomes stronger, as a muscle does, by use. Something 
 much more important is involved, and more in harmony with 
 the functions of the nerve system. Keeping in view the rela- 
 tion of the nerve centres to the nerve fibres, it implies a more 
 prompt and copious discharge of nerve energy from the centre, 
 1 Miiller'a Elements of Physiology, transl. by Baly, vol. ii. p. 939. 
 
4 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 nd more ready and powerful action of the nerve lines. The 
 eneral law has thus a double significance, bearing at once on 
 icility and on intensity of action. And for each of these 
 spects of the law there is distinct application to the nerve 
 entre, on the one hand, and to the lines of communication, on 
 be other. Facility must be interpreted as having two aspects, 
 lie one concerned with the discharge of nerve energy, the other 
 ri.th communication of influence along the lines, or ready 
 transmission along chosen tracts. Intensity must in like 
 lanner be viewed in a double relation, as it applies to amount 
 f energy put forth, and amount of work done. These aspects 
 f the general law are simply illustrated by the familiar facts 
 onnected with development of powers of observation and 
 Dcomotion in early life. The child at first sees objects promis- 
 uously, next is attracted by moving objects, or by those of 
 right colour, — and only by practice in the exercise of observa- 
 ion comes to concentrate on particular objects, or aspects of an 
 bject. So it is with locomotion. The child first attempts to 
 beady itself on its feet,— then to put one foot before the other 
 1 balancing the body, — and thereafter acquires the power of 
 anning without concern. The chick greatly excels the child in 
 asy control of its movements. From this it may follow that 
 diat the child does is greatly more complicated than what 
 tie chick does. I do not at present dwell on the question 
 used by this contrast, but only point out the illustration of 
 ae general law of the development of nerve power as illus- 
 rated in the early life of a child. More extended observation 
 onfirms this law. Illustrations are, however, more easily 
 btained from the motor nerves than from the sensory, because 
 lie discharge of nerve energy is more marked in the one case 
 lan in the other. On this account we more readily attribute 
 zcility to the action of motor nerves, intensity to the force of 
 npression received along a sensory nerve. But both phases 
 pply equally to motor and to sensory nerves. Thus the blind 
 lan, who depends largely on sensibility of the finger-points, 
 nds that the readiness of application and amount of impres- 
 ion are greatly increased by practice, unless, indeed, manual 
 ibour harden the skin and thus interferes with the natural 
 evelopment of sensibility of nerves. So as to the motor 
 
»!•] THE NERVE SYSTEM. 
 
 55 
 
 nerves, the violinist, as he becomes a skilled performer, finds 
 that he commands his instrument at once with more ease and 
 with more power. The nerve energy is turned easily in the 
 familiar direction, and the lines of communication are easily 
 worked. A deep cut into the left hand, occasioning injury to 
 the nerve, of the violinist destroys for the time his power, and 
 makes it needful for him, when the nerve lines have been 
 reunited, to regain and re-establish his power over the fingers 
 of that hand ; but the facility with which this is done illus- 
 trates the truth of the law whose applications are now under 
 consideration. 
 
 From the more general statement applicable equally to the 
 sensory and motor nerves, it is needful to pass to a more 
 restricted view of the application of the law as it is concerned 
 with the distinctive features of each class of nerves. 
 
 Repeated use of a sensory nerve results in increased suscepti- 
 bility of the conducting fibre. This is familiarly illustrated by 
 the quickness and acuteness of impression in the case of those 
 whose occupations make special demands upon distinct nerves 
 of sensibility. A person who has trained himself to distinguish 
 sounds in a mountainous district can discriminate both as to 
 quality and direction, while one who has not thus trained himself 
 cannot. One who is constantly at work amongst cloths of 
 different fabric can tell, by a touch of his finger, what an 
 inexperienced person could not do without careful inspec- 
 tion. There was in Glasgow a blind man known to me, whose 
 business was that of a dyer, and who could by touch most 
 accurately distinguish the colour of the cloth submitted to him. 
 The different effects of the dye employed could be discrimi- 
 nated by tactile impression. In such cases as those adduced 
 there is, I doubt not, more involved than illustration of 
 increased sensibility of nerve by training ; but I am content 
 meanwhile to take them simply as illustrating the point under 
 observation. Under this law we find the explanation of many 
 of the phases of sensibility peculiar to individuals. Some of 
 these are to be explained by a nervous sensibility originally 
 more acute than ordinary ; but most by induced susceptibility 
 under the law of activity now explained. , 
 
 In this relation it must, however, be kept in view that there 
 
56 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 is a very marked restriction upon the law of increased power 
 by frequency of use. Eestriction is imposed, not only by need 
 for rest, as in the case of all nerve fibre ; but by the risk of 
 overstrained use, either as the result of over-continuance at a 
 time, or too frequent excitement. In other words, the excit- 
 ability of the sensory nerves can be so acted upon as to induce 
 an irritability which interferes with easy and normal action of 
 the sensory nerves. 
 
 Attention must next be turned on the phase of the law as 
 specially applicable to motor nerves. Repeated use of a motor 
 nerve or set of nerves secures increased facility and power of mus- 
 cular control by means of the conducting fibre. This is illustrated 
 by acquired movements, such as those involved in swimming 
 or skating. The movement is at first difficult of accomplish- 
 ment. The felt uncertainty of movement occasions apprehen- 
 sion of danger. But repeated effort brings the motor nerves 
 more completely under control, making the movement not only 
 easy, but a source of pleasure. From this time the nerve 
 centre and the set of nerves brought into exercise have an 
 established relation. A facility of co-ordinated action is 
 established. It is equally true as a description of the result, 
 that the nerve energy passes easily to the nerve lines con- 
 cerned, and that the nerve lines have a predisposition or pre- 
 paredness for action. Hence the marked change of experience 
 consequent on established facility. 
 
 In this way also actions become associated or related, so that 
 they naturally attend upon each other. There is an actual 
 nerve relation established between the co-operating lines of 
 nerves. Every one has noticed how certain movements of the 
 eyebrows or expressions of the face attend upon actions such 
 as playing a wind instrument. Observation of any orchestra 
 will afford illustration. A distinguished cornet or clarionet 
 player may be seen constantly moving his eyebrows while 
 executing a passage requiring considerable effort. The action 
 of the eyebrows contributes nothing to the execution, yet any 
 effort to discontinue this needless muscular movement would 
 disturb the performer greatly. The actions are so co-ordinated, 
 that execution is easy as long as the association is allowed to 
 continue without concern. Effort to break the association 
 
III.] THE NERVE SYSTEM. 57 
 
 would require to be long continued, and would involve no 
 small degree of discomfort. That the association was altogether 
 unintentional makes no difference. Some explanation of the 
 association is found in the two considerations adduced by 
 Muller, 1 that " it is most easy for the will to determine whole 
 groups of muscles to action," and that " a voluntary movement 
 is more difficult the smaller the number of nervous fibres 
 requiring to be excited, and the smaller the part to be moved." 
 This is readily shown by the attempt to move a single finger 
 rather than the whole hand. 
 
 There is one thing, however, to be noted, which must have 
 careful consideration hereafter, that the most striking ex- 
 amples to which our attention can be turned are essentially 
 connected with voluntary action. The illustrative value of 
 cases would be enormously reduced, if we abstracted every- 
 thing which comes from exercise of volition, restricting our 
 observation to spontaneous nerve action. That the law of 
 increasing facility and efficiency applies to nerve energy and 
 nerve fibre as such, there can be no doubt ; but self-direction 
 so wonderfully utilises the law, that we could not properly 
 study the characteristics of the nerve system in man, did we 
 not mark the uniform presence of a voluntary element in all 
 the more striking examples of the increase of conducting 
 power in the sensory and motor nerves. 
 
 Beyond this subject arises the question concerning the ratio 
 of intensity in sensation, and the rate of transmission along a 
 sensory and a motor nerve. These questions have engrossed a 
 large amount of attention from Weber, Fechner, Wundt, Helm- 
 holtz, Du Bois-Eeymond, and others. To enter with any 
 minuteness into the methods and results of inquiry on these 
 points would carry me much beyond the limits I must assign 
 to myself. The questions, besides, are somewhat removed from 
 the main subject of consideration here, and may be touched 
 upon more cursorily. 
 
 Concerning the rate of increase of sensation, there is general 
 
 agreement as to the law which has been recognised as Fechner's 
 
 law. Increase of sensation does not keep pace with increasing 
 
 stimulation. But sensation is intensified in such a way that 
 
 1 Baly's transl., vol. ii. p. 938. 
 
58 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 equal increments of sensation correspond to equal relative 
 increments of impression. Thus 1 added to 100 gives the 
 same increase as 2 added to 200, or 3 to 300. Hence, judging 
 by our own experience, we can say, " where the intensity of 
 the sensation increases by equal quantities, the force of stimu- 
 lation is also increased by relatively equal quantities." Con- 
 siderable increase of the stimulating force gives only a slight 
 additional intensity of sensation. In its final form the law is, 
 that sensation increases according to the logarithm of the 
 fundamental impression. 1 
 
 The next point of interest is the rate of transmission of 
 influence along the nerve line. This question is applicable 
 equally to sensory and motor nerves. It is, however, most 
 readily tested by the action of the sensory nerve, inasmuch 
 as one person can supply the stimulating force, while the other 
 records the experience. Helmholtz, Konig, and others, have 
 been at special pains to illustrate this, by showing that the 
 stimulus is first applied, and quickly thereafter the person 
 affected gives the signal of his experience. Helmholtz finds 
 that there is diversity in the case of individuals, as may be 
 expected from the greater sensitiveness which some manifest. 
 As the result of a long series of experiments, he concludes 
 that the transmission of sensory impulse is, at the slowest, at 
 the rate of 28 yards per second, at the quickest, 32 yards per 
 second. Professor M'Kendrick has given drawings of the 
 ingenious instrument employed by Konig for testing the rate 
 of transmission. 2 
 
 From the general view of the functions of the two great 
 orders of nerve fibre, I proceed to consider briefly the nerves 
 of special sense. These, as nerves of sensation, come under 
 the ordinary laws of sensory nerves. They are dependent for 
 healthy action upon contact with the grey matter of the nerve 
 centre. They are distinguished by special terminal organs pro- 
 viding for susceptibility. They are further connected with lines 
 of motor nerves, and have their sensibility considerably affected 
 by this correlation. Touch, taste, and smell are most closely 
 
 1 Feohner'a Elemente der Psychophysilc, 1"° Th. 64 ; 2'' Th. 13. Wundt, 
 Grundziige der Physiologischen Psychologie, 301. M'Kendriok's Physiology, ' 
 P- 544. 2 Outlines of Physiology, p. 538. 
 
ni.] THE NERVE SYSTEM. 59 
 
 allied with the ordinary sensory nerve. It is indeed true that 
 hearing and sight imply modifications of touch, yet there is in 
 the case of these two a much more remarkable arrangement of 
 terminal organ requisite for the specific action of the nerve line. 
 
 The nerves of special sense, as previously remarked, are 
 principally connected with the head, and have thus a close 
 local relation with the brain. Hence they, with the motor 
 nerves which attend on them, are known as cranial or encephalic 
 nerves. In sight, smell, hearing and taste, the terminal organs 
 are dual in form, and hence there is a pair of nerves for each 
 sense. Touch has a multiform arrangement. It is indeed 
 associated with the whole surface of the body, though it is 
 concentrated in special form at the tips of the fingers. As it 
 is the sense most widely related to the nerve system as a 
 whole, it is in reality the typical form of all sense. Wherever 
 there is sense there is sensibility to impression, and that is 
 acted upon by contact in one form or another. 
 
 The olfactory nerves stand first in the order of cranial nerves, 
 and with smell, therefore, we begin the enumeration of the 
 special senses. The nasal passages have a twofold function to 
 fulfil, for in them we have the entrance of the air passages, for 
 breathing, as well as the distribution of the olfactory nerve. 
 The respiratory arrangement belongs to the floor of the nose, 
 the olfactory to the roof of the nose. This combination is of 
 great value in relation to the sense of smell, for the drawing 
 into the nasal passages of a current of air is an essential thing 
 for discrimination of odours. The upper portion of the nasal 
 passage is covered by a soft mucous membrane, on the surface 
 of which are numerous olfactory cells, which constitute the 
 terminal organ of the olfactory nerve. From each olfactory 
 cell a fibre is sent forward, which, according to Schultze, has 
 a fretted or brush-like appearance. Towards the deeper surface 
 of the membrane another fibre stretches from the cell, more 
 slender in appearance than the fibre at the surface. This 
 fibre is sometimes terminated in a point, sometimes bifur- 
 cated, and at other times flattened out. The olfactory nerve 
 fibres are spread out over the membrane in elaborate ramifica- 
 tions, and come into close relation to the olfactory cells. 
 They are gathered together in a . series of bundles (enumera- 
 
60 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 tions vary from 15 to 20, and even 25 bundles), which termi- 
 nate in a bulb at the base of the brain. This extended and 
 intricate distribution provides an exceedingly sensitive surface 
 liable to be affected by the most delicate influences. The 
 commonly received opinion is that odorous particles float on 
 the atmosphere, and stimulate the brush-like filaments of the 
 olfactory cells, making an impression which is transmitted 
 to the nerve centre. It cannot be said that these facts have 
 been scientifically established, any more than the relations of 
 the olfactory cells and the fibres have been traced, but the 
 analogies of the nerve system favour this view. The bulb in 
 which the olfactory nerves terminate at the base of the brain 
 partakes of the nature of a special nerve centre, consisting of 
 grey matter as well as of white, and the grey matter contains 
 rounded and pyramidal cells, packed in nerve glue, just as in 
 the brain proper. 
 
 Second in order of cranial nerves are the pair of optic nerves, 
 proceeding to the organs of vision. These terminal organs, 
 being open to observation, are familiar to all, yet the intricacy 
 of structural arrangement is such that it is difficult to represent 
 to ourselves the unity which is the result of so many com- 
 binations. The eyeball is protected in front by the eyelid, 
 which is covered within with soft mucous membrane, which is 
 reflected on the front of the eyeball. Above the orbit is the 
 lachrymal gland, whence comes the tear supply, the fluid 
 passing over the cornea, and being carried off by the lachrymal 
 ducts into the nose, so as to mingle with the mucous secretion 
 of the nostril. The structure of the eyeball will be best 
 illustrated by the aid of figure 1 6. 
 
 The exposed surface of the eyeball (the cornea, co), which 
 is convex without, concave within, is translucent. It is 
 lined behind by an elastic membrane not more than T^th 
 part of an inch in thickness, over which is a soft layer of 
 cells, which are spread round the membrane. The sub- 
 stance of the cornea consists of layers of soft fibres, to the 
 number of about 60, laid one in front of the other, which are 
 closely connected together, with numerous delicate cells dis- 
 persed throughout. This body depends for its transparency on 
 the distribution of the fibres. Any derangement of them is 
 
Iu -1 THE NERVE SYSTEM. 61 
 
 apt to interfere with this. 1 Immediately behind this external 
 body is a chamber (aq) filled with a clear watery fluid, essential 
 for the translucency of the external portion of the eye. To 
 the rear of this chamber is the lens (L), known as the 
 
 Fig. 16.— STRUCTURE OF THE EYEBALL. 
 
 (From Turner's Anatomy.) 
 
 "Diagrammatic section through the eyeball. <$, conjunctiva; co, cornea; Sc, sclerotic; ch, 
 choroid ; pc, ciliary processes ; mc, ciliary muscle ; O, optic nerve ; R, retina ; I, iris ; aq, 
 anterior chamber of aqueous humour ; L, lens ; V, vitreous body ; Z, zonule of Zinn, the 
 ciliary process being removed to show it ; p, canal of Petit ; m, macula or yellow spot. 
 The dotted line behind the cornea represents its posterior epithelium." 
 
 crystalline lens. This is a solid transparent body, albuminous 
 in nature, and in shape convex on both sides. When broken 
 up, it is found to consist of a solid hard nucleus in the centre, 
 and it is encompassed by a series of layers, which are harder 
 towards the interior, softer as they approach the surface. 
 Converging on the central point of each convex surface are a 
 series of lines, which give a star-like appearance to the front 
 and back of the lens. 
 
 Between the fluid chamber and the crystalline lens, with an 
 opening in the middle, is the coloured membrane, known as the 
 iris (I), which gives the distinctive colour to the eyes of indi- 
 
 1 Quain's Anatomy, vol. ii. p. 715. 
 
62 THE RELA TIONS OF MIND AND BRAIN. [chap. 
 
 viduals. This membrane, being muscular, is capable of contrac- 
 tion and expansion, allowing for a continual change in the 
 size of the opening, as the requirements of vision may demand. 
 This opening in the membrane is what we speak of as the 
 pupil of the eye. Around the margin of the opening there 
 is a narrow band of muscular fibre, entwined among which are 
 fibres which radiate outwards to the circumference of the mem- 
 brane. By means of these fibres, the iris regulates the size 
 of the pupil, and the amount of light transmitted through 
 the lens. Another small muscle, the ciliary muscle (po), sur- 
 rounds the outer margin of the lens, on which it acts so as to 
 modify the curvature of its anterior surface, and adapt the eye 
 to the vision of both near and distant objects. 
 
 Behind all the parts already described is the vitreous body 
 (V), which is by far the largest part of the eyeball. It is 
 nearly spherical, but having in front a hollow in which the lens 
 rests. It is full of fluid, containing salt and albumen, which is 
 enclosed within a thin clear membrane, and is completely 
 transparent. It acts as the support of the retina (E), which is 
 spread over it. 
 
 The retina is a delicate membrane, containing the terminal 
 portion of the optic nerve ; for it is at this point we first reach 
 the sensory nerve. This membrane is sensitive to light, and is 
 known as the nerve tunic. By the investigations of Schultze, 
 the retina has been shown to be elaborately constructed, having 
 behind its anterior limiting membrane a layer of nerve fibre, — 
 behind these a layer of nerve cells, — behind these four layers 
 of granulated bodies, — and, last of all, a membrane consisting 
 of rows of bodies, alternately longer and shorter, the longer 
 being like circular rods, the shorter like sharp-pointed cones. 
 This elaborate formation will be best understood by reference 
 to figure 17. 
 
 The network of the retina can be easily recognised by a simple 
 experiment. Let any one perforate a card in the centre with 
 an ordinary-sized pin, and, standing near the window or in 
 the open air, keep moving smartly the little aperture in front 
 of the eye. He will thus gradually throw the concentrated 
 light in upon the whole chamber. He will then see the net- 
 work with a thin obscure space in the centre. The experiment 
 
III.] 
 
 THE NERVE SYSTEM. 
 
 63 
 
 is of the easiest kind, but is apt to weary the organ, if often 
 repeated. Purkinje's experiment by means of a moving candle 
 in an otherwise dark room serves the same purpose. It is 
 described in Muller's Physiology} This form of the experi- 
 ment has the advantage of showing the retina of both eyes at 
 once. 
 
 Fjg. 17.— STRUCTURE OF THE RETINA. 
 (From Turner's Anatomp, modified from Sehultze.) 
 
 " Diagrammatic antero-posterior section through the retina to show the several layers : — 
 1. Membrana limitans interna ; 2. Layer of optic nerve fibres ; 3. Layer of ganglion cells ; 
 4. Internal granulated (molecular) layer ; 5. Internal granule layer ; 6. External granu- 
 lated layer ; 7. External grannie layer ; 8. Membrana limitans externa ; 9. Bacillary 
 layer, or layer of rods and cones ; Ct, Connective tissue of the retina." 
 
 To proceed, however, with the description of the terminal 
 organ. Just opposite the pupil, and at the centre of the retina, 
 there is a yellow spot about one-twentieth of an inch in length, 
 with a depression in the middle. The yellow colour results 
 from the presence of pigment in the anterior layers. This part 
 is somewhat thicker, except at the depression, and softer than 
 the rest. The nerve fibres are absent from this part, and it is 
 mostly occupied with a series of slender cones packed closely 
 together. 2 
 
 A little to the inner side of this yellow spot the optic nerve 
 enters the retina, and thence distributes its fibres towards the 
 front border of the retina. These fibres are very minute, " the 
 largest of them being only about l-6000th part of an inch in 
 diameter, whilst the smallest are no more than from l-30,000th 
 to l-50,000th of an inch." 3 
 
 Outside the retina is an intermediate coating or membrane 
 (the choroid), which contains pigment, and carries a large 
 
 1 Vol. ii. p. 1163. 
 
 2 Turner's Anatomy, p. 340. Carpenter's Physiology, p. 696. 
 
 3 Carpenter's Physiology, p. 696. 
 
64 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 supply of blood-vessels : and outside this again is a thick coat 
 {the sclerotic), fibrous in nature, white in colour, and altogether 
 opaque. 
 
 Thus it is obvious that the eyeball, with its translucent 
 structure in front, and its thick opaque coating behind, cover- 
 ing in about four-fifths of the whole, is a camera-obscura. 
 The cornea, convex in front, concave behind, — and the lens, with 
 its double convex surface, — constitute the refracting arrange- 
 ments, by which the rays of light from an object are directed 
 upon the retina, producing an inverted image of the object, 
 with all the variety of effects which the different rays indicate. 
 These different rays touch the sensitive surface of the retina, 
 the effect being more especially concentrated upon the accumu- 
 lation of slender cones at the yellow spot. The various effects 
 form a combined impression, and throw their influence upon the 
 optic nerve. This optic nerve is a sensory nerve, subject to all 
 the laws applicable to nerves of this order, but it is distinguished 
 by special characteristics which adapt it to a set of effects pro- 
 duced by the agency of light. Here, therefore, the effects are 
 twofold, — the effect common to all sensory nerves when stimu- 
 lated, that is, sensibility; and the effects peculiar to nerve stimu- 
 lated by rays of light brought to a focus through a translucent 
 body. The optic nerve, which is large, firm, and round, takes 
 its course direct for the part of the nerve centre known as the 
 optic commissure, where the nerves from the two eyeballs are 
 joined together, forming a flattened band. These two optic 
 nerves are quite distinct, but each gives off to its companion a 
 series of fibres by means of which they are closely connected. 
 
 In the condensed description now given of the organ of 
 vision the leading facts are included which physiological 
 science has established ; and these are concerned exclusively 
 with the structure and working of the mechanism, without 
 explanation of the resultant experience. The explanation of 
 this last is a matter of great difficulty — a difficulty which has 
 not yet been overcome. Our best course is to mark clearly 
 the different steps by which physiology guides us to the 
 landing-place actually reached. First, attention is directed to 
 the arrangement of lenses, the first convex on the outer 
 side, concave on the inner; the second double convex. By 
 
Hi.] THE NERVE SYSTEM. 65 
 
 the situation of these two, the rays of light are brought to a 
 focus and carried directly to the back wall of the darkened 
 chamber, so that every point of an object is represented by 
 a point in the image traced on the retina. The influence of 
 light thus takes effect upon the tracery of the retina. It has ' 
 been shown by Professor F. Boll of Eome, and confirmed by 
 Professor W. Kiihne of Heidelberg, that this network possesses 
 colouring matter, named by them " sight purple," which, by 
 chemical action under the effect of the light, produces the 
 representation of objects brought within the range 'of vision. 1 
 Secondly, there is a twofold plan of adjustment connected with the 
 use of the crystalline lens — the one concerned with the use of 
 the iris or screen by which part of the lens is covered, the other 
 with the management of the lens itself, which is capable of 
 being somewhat shifted in relation to the outer transparency. 
 The screen is so fitted as to prevent certain rays striking the 
 sides of the lens ; and it can be closed more effectually over 
 the lens, so as to diminish the aperture lying open to the rays. 
 In addition, the lens itself is capable of being acted upon 
 by the ciliary muscle in such a way as to increase its con- 
 vexity, and so carry its surface forward in closer proximity to 
 the translucent cornea. By this double provision there is 
 the possibility of adjustment to the relative distance of the 
 object of vision. Thus if an object be first seen at a distance, 
 and then rapidly carried towards the observer, the focus can 
 be adapted to its approach. Thirdly, there is the possibility 
 of seeing the retina itself, in a manner closely analogous to 
 that by which we see an external object. This circumstance 
 proves, in accordance with the experiments of Boll and 
 Kiihne, that the light operates directly upon the sensitive 
 surface. It is thereby shown that the sensitiveness of the retina 
 is the real key to our experience by vision. Miiller takes this 
 view of the bearing of the experiment of Purkinje. He says : 
 " We have here a distinct demonstration of the axiom that in 
 vision we perceive merely certain states of the retina, and that 
 the retina itself is the field of vision — dark in the unexcited, 
 illuminated in the excited condition." 2 This view is borne out 
 
 1 Nature, Feb. 1, 1877, vol. xv. p. 296 ; article by Professor Gamgee. 
 
 2 Elements of Physiology, Baly's translation, vol. ii. p. 1163. 
 
 E 
 
66 THE RELATIONS OF MIND AND BRAIN. [chai>. 
 
 by the spectra, sometimes coloured, sometimes colourless, we 
 are capable of seeing whea the eyelids are closed, after having 
 looked steadily for a time at some bright object. The reality of 
 such spectra is familiarly known by the result of looking at the 
 sun. It is also illustrated by looking steadily at the window for 
 a time, then closing the eyelids, and holding the hand or a hand- 
 kerchief over them. A luminous representation of the window 
 appears, the cross-bars being at first dark, the panes bright. 
 If there be any obscurity or uncertainty in the representation, 
 it is often sufficient to remove this, merely to raise the hand 
 from the eyes, and gently, though smartly, rub the eyelids with 
 the tips of the fingers. The cross-bars of the window then 
 appear bright, and the panes of glass darker. Additional testi- 
 mony is gathered from the spectra of coloured objects. These 
 spectra are always coloured, and " their colour is not that of 
 the object, or of the image produced directly by the object, 
 but the opposite or complementary colour." 1 In this way the 
 spectrum of a red object becomes green when the eyelids are 
 thoroughly closed against light. Fourth, the yellow spot in 
 the centre of the retina is the specially sensitive part. This 
 yellow spot contains multitudes of the cones of the retina 
 compactly arranged. There is here a difficulty in carrying 
 through the explanation of the action of the organ, because the 
 cones in the yellow spot, or the rods and cones in the other 
 parts of the retina, are not proved to be in anatomical continuity 
 with the fibres of the optic nerve. We can only conjecture 
 that there is communication between the cones and the optic 
 nerve fibres, thereby providing for the impression of light being 
 transmitted to the nerve centre. 
 
 Whether the inverted picture on the retina performs any 
 part beyond that of producing distinct impressions according 
 to the varieties of surface represented, may be doubted. Some 
 have supposed that this picture, acting upon the sensitive nerve, 
 is reproduced on the grey matter of the brain. But there is 
 difficulty in assigning to the sensory nerve a power of pro- 
 ducing such an effect as copying a pictorial representation of 
 an object, and it is at variance with the recognised functions 
 
 1 MUller's Elements of Physiology, vol. ii, p. 1183. Brewster's Optics, 
 p. 430, § 209. 
 
ni.] THE NERVE SYSTEM. 67 
 
 of the grey matter to suppose that it is a sensitive surface 
 capable of receiving pictorial impressions. If the retina is 
 expressly fitted for this, the cell tissue of the brain is not so 
 fitted, and has other work assigned to it. But, even if it were 
 allowed that the picture produced on the retina is succeeded 
 by a second picture traced on the grey matter, a more serious 
 difficulty lies behind. The grey matter receiving the picture 
 is on this supposition also an active body, endowed with 
 power to see what is traced on its surface. How can we con- 
 sistently assign two functions so exceedingly dissimilar to the 
 same nerve tissue ? 
 
 Connected with this question of communication with the 
 nerve centre, there is the further point which arises on account 
 of binocular vision. The two eyeballs, each with its distinct 
 retina, are receiving separate representations, and transmitting 
 separate impressions to the nerve centre. There are in the 
 structure of this organ, as in the organs of smell and hearing, 
 distinct arrangements for securing harmony of action on the 
 part of the two terminal organs, and consequent unity of effect. 
 There is first and specially in the case of vision, co-ordination 
 of motor nerves, which are used in directing the eyes towards 
 the object; and there is harmonious action within each eye- 
 ball for adjustment of focus. These arrangements provide for 
 similarity of impression on the retinae. Next, the two optic 
 nerves are traced back to a point of junction in the nerve 
 centre, where, interlacing to some extent, provision is made for 
 harmony or unity of result, as in the case of sensory nerves 
 proceeding to the opposite hemispheres, yet connected together 
 by lines of communication existing in the nerve centre. 
 
 Taking now a survey of what is known concerning the struc- 
 ture and action of that portion of the nerve system devoted to 
 vision, it is plain what constitutes the scientific difficulty. It 
 is to find an answer to the question, What is the relation of 
 the sensitive retina to " the sensorium " or receptive centre in 
 the brain ? How does the influence of light on the one pro- 
 duce an effect on the other ? Or, as Midler has put it, " the 
 question to be determined is the following : Where is the state 
 of the retina perceived ; in the retina itself, or in the brain ?" 
 On this perplexity Miiller adds : " one of the most difficult 
 
68 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 problems in physiology is that relative to the respective influ- 
 ence of the retina and sensorium in vision. This department 
 of the physiology of the senses may be correctly styled the 
 metaphysical, since we are at the present time totally destitute 
 of any empirical means of elucidating it." 1 Now, this is a 
 purely physiological question, and it must so remain, whether 
 a solution is forthcoming or not, for there is no metaphysical 
 question involved. Psychology can offer no help, for personal 
 experience tells nothing of the transmission of influence from 
 the peripheral extremity of the sensitive nerve to its other 
 extremity in the nerve-centre. Speculative reason does not 
 deal with such a question, whatever may be said for "the 
 scientific uses of the imagination," wisely and eloquently in- 
 sisted on by Professor Tyndall. "We have here an unfinished 
 piece of science. Nothing but persistent scientific inquiry can 
 make up the deficiency. Until this is achieved we must simply 
 own that there are some physiological problems which still 
 baffle our researches. When science proclaims that there is a 
 mystery in this high phase of organic action, it must be allowed 
 so to testify. Philosophy will not interfere, but will patiently 
 wait on science, as in duty bound. 
 
 Meanwhile we can but fall back on the general laws of the 
 nerve-system. The optic nerve is confessedly a sensory nerve. 
 It is granted that light acts upon the sensibility of the cones 
 and rods of the retina, and that influence is thence conveyed to 
 the optic nerve. Proceeding on these facts, we must say, in 
 accordance with the general law of nerve action, that influ- 
 ence is transmitted to the nerve centre. Prom this physio- 
 logical position we must next pass over into the region of 
 experience, and say that we are conscious of sensation conse- 
 quent on the influence of light, and at the same time we have 
 a perception of an object. The latter appears the more promi- 
 nent in our experience, so much so that we recognise less of 
 sensation in the exercise of vision than in the use of any other 
 special sense. In accordance with this, sight is spoken of as 
 " the most intellectual of all the senses." 2 But the fact that 
 
 1 Physiol. Trans., vol. ii. p. 1163. 
 
 2 On the Intellectual Relations of the Special Senses, v. Professor Bain's 
 Senses and Intellect, pp. 160. 176, 254. 
 
"!•] • THE NERVE SYSTEM. 69 
 
 there is by means of the eye sensation of light, is amply illus- 
 trated by what has been already said as to the luminous spectra 
 observed when the eyes are closed. This is fully confirmed by 
 the facts which show that the sensation of light can be pro- 
 duced by mechanical, and also by electric stimulation of the 
 optic nerve. I do not here enter upon the grand perplexity 
 belonging to a philosophy of perception as connected with the 
 theory of vision, which would need a treatise to itself, if it 
 were to be discussed. Kecognising the special difficulties for 
 mental philosophy which are encountered in the attempt to 
 construct a theory of external perception, I only remark that it 
 is no marvel if psychology has its own share of perplexity, 
 attendant on, and largely caused by, the admitted perplexity of 
 physiological science. While, however, we mark off the bound- 
 aries of this unconquered region, it is to be observed that one 
 thing universally admitted — and to be valued accordingly — is 
 this, that there is communication from the external world to 
 the nerve centre, as by all the other special senses. The per- 
 plexity connected with a theory of external perception does 
 not involve perplexity as to the existence of an outer world, 
 but is in great measure occasioned by the clearness and fulness 
 of evidence of the fact that individual life is distinct from an 
 outer region of existence. If there be a mystery as to their 
 relations, the distinction of the regions is nevertheless clear. 
 Equally clear is the distinction between the two classes of 
 problems involved. One set is connected with light, its reflec- 
 tion and refraction, the representation on the sensitive surface 
 of the purple-coloured membrane within the eyeball, and the 
 transmission of sensory impulse, together with the relation of 
 motor nerves to the management of the organ upon which the 
 light operates. The other class of problems is connected with 
 personal control of the motor nerves just mentioned, and per- 
 sonal action in the acquisition of knowledge by means of the 
 organ of vision. 
 
 I shall next take the Auditory Nerve, along with the organ of 
 hearing, as another form of special sense calling for more minute 
 description in view of the questions to be afterwards raised. 
 Seventh in order of the cranial nerves is the pair of auditory 
 nQrves, connected with their own special terminal organs. 
 
70 THE RELATIONS OF MIND AND BRAIN. '[chap. 
 
 The ear consists of three perfectly distinct divisions, which 
 will be best described by proceeding from the external portion 
 inwards. The following diagram will illustrate their relations 
 and form. The outer portion of the ear is irregular, or con- 
 
 Fia 18.— THE EAR AS SEEN IN SECTION. 
 
 (From Turner's Anatomy.) 
 
 " a, helix ; 6, anti-tragus ; c, anti-helix ; d, concha ; e, lobule ; /, mastoid process ; g, portio 
 dura ; h, styloid process ; 1c, internal carotid artery ; I, Eustachian tube ; m, tip of petrous 
 process ; n, external auditory meatus ; o, membrani tympani ; p, tympanum ; 1, points to 
 malleus ; 2, to incus ; 3, to stapes ; 4, to cochlea ; 6, 6, 7, the three semicircular canals ; 
 8 and 9, portio dura and portio mollis. (After Arnold.)" 
 
 voluted in surface. The "vibrations or waves of sound falling 
 upon it are reflected, and pass down the passage or canal 
 (external meatus), striking from side to side, until they reach 
 a membrane which completely closes the passage, commonly 
 spoken of as the drum of the ear, or, more properly, head 
 of the drum (membrana tympani), which is so placed as to 
 incline downwards, or in an oblique direction. Upon this the 
 wave of sound beats. This membrane situated at the end of 
 the outer passage has a concave form, and is consequently 
 convex in the inner cavity or middle ear. It consists of three 
 layers, the outermost of which is a continuation of the skin ; 
 the central layer consists of a series of fibres, some of which 
 are arranged as radii, others in a circular manner ; the inner- 
 
I"-] THE NERVE SYSTEM. 71 
 
 most is a mucous layer, and is a part of the mucous lining of 
 the tympanum. 
 
 Just beyond this membrane is a second division of the organ, 
 constituting quite a distinct chamber, known as the drum (tym- 
 panum), or middle ear. This cavity has an opening at its base, 
 which is the entrance of a tube or pipe {Eustachian tube), which 
 communicates with the back* part of the throat, and is the 
 channel for admission of air into the tympanum. The middle 
 ear is thus a cavity filled with air, upon which the beat made 
 on the drumhead may act, thereby starting in the tympanic 
 chamber a series of wave vibrations, Within this chamber is 
 a series of small bones, placed in contact with each other for 
 the transmission of sound. The first bone has a rounded 
 head, a narrow neck, and an elongated handle below, the 
 end of which is attached to the membrane separating the 
 outer from the middle ear. Its shape has led to its name, 
 the hammer (malleus). ]&om this bone a series of ligaments 
 proceeds, by means of which it is securely fastened to the 
 walls of the chamber. The head of the hammer rests on the 
 central bone, known as the anvil (incus), which presents a 
 broad surface to it. From the body of the anvil a process 
 passes inwards, and is jointed with the third and smallest of 
 the bones, called, from the peculiarity of its shape, the stirrup 
 (stapes). These three bones are so connected together as to 
 form a continuous communicating medium across the chamber 
 of the middle ear, and they move on each other by means of 
 small muscles. The next point of interest here is the inner 
 wall of this chamber. Its special features are grouped oppo- 
 site to the outer wall formed by the tympanic membrane. 
 More particularly may be noticed an opening of an oval shape, 
 upon which the base of the stirrup bone rests. This opening 
 is protected by a thin membrane, and is named the oval 
 window (fenestra ovalis), and this window corresponds with a 
 division of the inner ear named vestibule. Below the oval opening 
 is a round-shaped opening, also covered with a thin membrane. 
 This is known as the round window (fenestra rotunda), com- 
 municating with another division of the inner ear, named the 
 cochlea. The three bones of the tympanum thus constitute a 
 direct line of communication across the chamber, the lower end 
 
72 THE RELA TIONS OF MIND AND BRAIN. [chap. 
 
 of the first bone resting on the outer membrane, the base of the 
 third resting on the oval window. 
 
 The relations of the three divisions of the organ may be better 
 understood by reference to the following diagrammatic view : — 
 
 Flo. 19.— THE INTERNAL ARRANGEMENTS OP THE EAR. 
 
 {From Professor M'Kendrick's Outlines of Physiology.) 
 
 " Diagrammatic view of the auditory apparatus (Bmunis). A, external ear ; B, middle ear ; C, 
 internal ear ; 1, concha ; 2, external auditory passago ; 8, tympanum ; 4, membrana tym- 
 pani ; 5, Eustachian tube ; 6, mastoid cells ; 7, malleus ; 8, incus ; 9, stapes ; 10, fenestra 
 rotunda ; 11, fenestra ovalis ; 12, vestibule j 13, cochlea ; 14, scala tympani ; 16, seala 
 vestibuli ; 16, semicircular canal." 
 
 We next come to the third division or the inner ear, the inner- 
 most recess, in which the extremities of the auditory nerve 
 are distributed. "What is found within this chamber may be 
 viewed in two parts, the upper and under, both of which are 
 elaborately constructed. These two parts are respectively con- 
 nected with the upper and . under windows of the middle ear. 
 Immediately to the inner side of the upper or oval window 
 there is the vestibule. As we look towards its upper and 
 back wall, five openings may be seen (fig. 20), which are the 
 ends of three semicircular canals, named the superior, posterior, 
 and external. Two of these canals, the superior and posterior, 
 unite near the vestibule, thereby making one opening suffice 
 for the extremity of two of the canals. This will appear from 
 figure 20, which gives a view of the relations of the semi- 
 circular canals, and of the cochlea. 
 
 Directing attention first upon the semicircular canals, im- 
 portance is to be attached to their shape, their internal struc- 
 
!»•] THE NERVE SYSTEM. 
 
 73 
 
 ture, and their relative position. It will be noticed by reference 
 to the opposite sides of the two vertical canals, that there is 
 an enlarged opening at one end of each. This holds true also 
 of the horizontal canal, though it is not shown in the figure. 
 These enlarged spaces are known as the ampullce of the 
 canals. The outer portion of the canals, as well as of the 
 cochlea opposite to them, is a structure of bone. Inside the 
 canals formed of bone is a membranous structure of similar 
 form, but considerably smaller 
 in size. This membranous 
 structure, though attached on 
 one side, floats in a clear fluid, 
 known as the surrounding 
 lymph (perilymph), and is also 
 filled with fluid, known as the 
 interior lymph (endolymph). Flf] . 20. -the labyrinth op the 
 " The membranous structure innermost chamber op the ear. 
 
 , . . (From Turner's Anatomy.) 
 
 supports numerous minute , <TV ,,. . » 1 ■ «. ™ 
 
 rr ^ " Diagram of the membranous Labyrinth. DC, 
 
 ramifications Of the auditory ductus coohlearis ; dr, ductus reunions ; S, 
 
 "1 Q -1 • j --I + J j sacculus ; U, utriculus ; dv, ductus vesti- 
 
 nerve. DO aiStriDUtea and buli ; SC, semicircular canals. (After WaX- 
 
 supported, these ramifications <%«•.)•• 
 
 are sensitive to the slightest influence of movement which 
 may occur in this innermost chamber, consequent on the pro- 
 pagation of sound-waves across the tympanic chamber. 
 
 Besides the auditory impressions produced by sound-waves, 
 it has been observed that the semicircular form of the canals, 
 filled as described, is fitted to secure sensitiveness to a rotatory 
 motion of the body itself. Professor Crum Brown of Edin- 
 burgh University directed attention to this in a paper laid 
 before the Eoyal Society of Edinburgh in 1874, afterwards 
 published in amplified form. 2 Attention had been directed 
 to the same point shortly before, by Professor Mach of Prague, 
 and Dr. Breuer of Vienna. Professor Mach afterwards discussed 
 the whole question in a treatise on the sensations connected 
 with movement, 3 agreeing more fully with Professor Crum 
 Brown than he was at first prepared to do. 
 
 1 Qnain's Anatomy, vol. ii. p. 573. 
 
 2 Jour, of Anat. and Physiol., vol. viii. p. 327. 
 
 3 Grundlinkn der Lehre von den Bewegungsempfindmgen. 
 
74 THE RELA TIONS OF MIND AND BRAIN. [chap. 
 
 The internal structure and the relative positions of the semi- 
 circular canals clearly fit them for sensitiveness to rotatory 
 motion. When movement begins, the fluid within is at rest, 
 and only gradually becomes affected. As stated by Professor 
 Crum Brown, — " the perilymph lags behind, and thus the 
 membranous canal, which floats iir the perilymph, does not 
 immediately follow the motion of the bony canal." But when 
 both come under the influence, "the relative motion of the 
 bony and the membranous canal must produce a pulling or 
 stretching of the forward end of the membranous canal." 1 
 Some modification of the theory falls to be made on account of 
 the membranous canal being attached to the bony canal. Con- 
 firmation of the theory is found, however, in the fact that " when 
 rotation at a uniform angular rate is kept up for some time, 
 the rate appears to the experimenter to be gradually diminish- 
 ing, and to cease altogether after a time." 2 
 
 The question here arises, how can we in this way be aware 
 of anything more than movement, affecting the sensoiy nerve ? 
 For, as Professor Crum Brown says, " As far as we know, a nerve 
 current can vary only in intensity, and not in kind ; so that, if 
 irritated at all, whether by right-handed or by left-handed 
 rotation, the nerve would convey the same message to the 
 central organ ;" 3 that is to say, would simply convey an impres- 
 sion of motion, without indication of its direction. This diffi- 
 culty Professor Brown meets by reference to the ampullae or 
 widened mouths situated at only one end of each semicircular 
 canal, and to the fact that each canal has its own distinct axis 
 relatively to the head or cranium. There is a widened mouth 
 at only one end of each canal, and he supposes that it is only 
 when the perilymph moves inwards from that mouth that the 
 canal becomes a sensitive organ as to rotatory motion. There 
 are three canals in each ear. " In each ear there is one 
 canal (the exterior) in a plane at right angles to the mesial 
 plane, and two other canals (the superior and the posterior) in 
 planes equally inclined to the mesial plane." 4 According to the 
 position of the head as it is moved will be the axis of move- 
 
 1 Proceedings of Royal Soc, Ed., 1873-74, p. 256. 
 
 2 Jour, of Anat. and Physiol., vol. viii. p. 328. 
 
 3 Jour, of Anat. and Physiol, vol. viii. p. 330. * lb. p. 331. 
 
ni.] THE NERVE SYSTEM. 75 
 
 ment, and in this way the sensibility to rotatory movement 
 will be found sometimes in one canal, sometimes in another. 
 This seems a natural explanation of our sensibility to rotatory 
 motion, though it leaves unexplained the singular and painful 
 experience of giddiness, often felt without any rotatory motion. 
 Hearing is the result of sound-waves in the atmosphere passing 
 into the outer ear, causing movement in the intermediate 
 chamber, and extending the same effect into the innermost 
 ' chamber, there awakening the sensation of sound ; it is, there- 
 fore, quite in harmony with the structural and functional 
 characteristics of the organ, to conclude that the canals of the 
 innermost ear should be sensitive to rotatory motion, and that 
 the lymph should, consequent upon movement, act upon certain 
 fibres of that sensory nerve which is organically the auditory 
 nerve. It would hardly follow, however, that we should 
 therefore speak of the effect as a special sense of rotatory 
 motion. Such sensibility must be regarded as one phase of 
 sensitiveness to motion, which is a common feature at other 
 parts, such as the fingers. 
 
 Concentrating now, however, on the structure of the ear as 
 bearing on auditory effects, it is needful to direct attention 
 to the vestibule and cochlea. The vestibule, like the semi- 
 circular canals, has a bony wall, and in its cavity is the fluid 
 perilymph in which the membranous vestibule is suspended. 
 It will be seen from fig. 20 that the vestibule is in two 
 divisions, the larger (U) being the vestibule to the semicircular 
 canals ; the smaller (S) the vestibule to the cochlea ; and these 
 two are connected by a narrow neck extending from the lower 
 portion of each. From the inner walls of the membranous vesti- 
 bule slight hair-like fibres spring from cells connected with the 
 auditory nerve. The smaller part of the vestibule is connected 
 with the cochlea. The cochlea is a tubular passage, in shape 
 not unlike the shell of a common snail, wound spirally about 
 a central pillar or modiolus. The narrow end of this body 
 rests against the wall, and occasions the prominence appearing 
 in the intermediate chamber between the two windows. The 
 passage gradually diminishes in area up to the apex. This 
 passage is divided into three spiral chambers, named scala 
 vestibuli, scala tympani, and scala intermedia. The scala vesti- 
 
76 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 buli and scala tympani contain perilymph continuous with the 
 perilymph of the vestibule and semicircular canals. The scala 
 intermedia contains endolymph continuous with the endolymph 
 within the smaller or cochlear portion of the vestibule (fig. 20, 
 S). The walls of these scalse are formed partly of bone and 
 partly of membrane, and the membranous wall of the scala 
 intermedia is called the membranous cochlea, which contains 
 numerous terminal branches of the auditory nerve. Here 
 also " a remarkable arrangement of cells exists, which pre- 
 sents an appearance that has been compared with the key- 
 board of a piano, and has been named the organ of Corti." 1 
 A series of arches formed by means of rods rises from a broad 
 base, meeting at the key of the arch, where they widen out to 
 a broad head. In connection with these there is a series of 
 conical cells, which throw out a great number of fine hair 
 lines, like tongues of the most delicate tuning forks, liable to 
 be affected by the very slightest vibration of the membranous 
 cochlea, and of its endolymph. 
 
 Such is the elaborate structure of the inner chamber, 
 which is the true ear, to which the other chambers are only 
 conducting passages. This innermost ear is filled with fluid 
 as the medium for conveying vibrations through its com- 
 plicated windings. Throughout its several divisions the ter- 
 minal arrangement of the auditory nerve is spread, having 
 numerous ganglia, from which are sent out minute nerve fibres. 
 Under these arrangements the ramifications of a sensory nerve 
 are spread out to receive the impressions of every vibration 
 which the wave-sounds may stir. How this impression produces 
 the distinct effect which we denominate hearing of sound, it is 
 impossible for us to tell. But as to the mechanical agency by 
 which the nerve is affected, we may conclude that the fluid 
 is set in motion, and begins to circulate through all the 
 recesses, that the vibrations influence the minute hair lines, 
 and that by this means the varied impressions familiar to us 
 are made on the ramifications of the sensory nerve. Here, 
 adopting the words of Mr. Lewes, " viewed on the physiological 
 side, is the succession of neural tremors." 2 
 
 1 Turner's Anatomy, vol. i. p. 370. 
 
 2 Problems of Life and Mind, vol. i. \>. 119. 
 
HI.] THE NERVE SYSTEM. 77 
 
 In the case of the organ of hearing, the entire structure 
 stands continually open to impression from without. There is 
 no such power of regulation as belongs to the organ of vision. 
 This organ thus presents a problem somewhat different in 
 form from that raised by the organ of vision. Here our main 
 inquiry concerns the interpretation of the impressions which 
 reach the brain from this organ, and of the increased facility 
 gradually attained in discriminating sounds. 
 
 Having thus particularly described the terminal arrange- 
 ments connected with the nerves of smell, sight, and hearing, 
 sufficient materials are at command for dealing with the main 
 question to be discussed, so far as that is illustrated by the 
 special senses. It seems, therefore, unnecessary for my pur- 
 pose that I proceed to describe the arrangements by which the 
 tongue is adapted for receiving the impressions of taste, or the 
 provisions for sensibility over the surface of the body, or for 
 sensibility to muscular movement. The form of the question 
 to be pressed is in reality the same in all cases, since the uni- 
 form provision for sensation is a sensory nerve, with special 
 adaptations at the peripheral extremity. The specialities in 
 the modes of sensation are provided for by specialities of 
 terminal organs. The three most remarkable examples have 
 been described in detail. From these descriptions it appears 
 that the terminal organs are analogous to the terminal part of 
 the ordinary sensory nerve. But, in addition to the common 
 characteristic, the special terminal arrangements show minute 
 provision for varied influences and for discrimination of the 
 varieties. Thus there is provision for distinction of odours ; of 
 form -and colour, and even of slightly differing shades of the 
 same colour ; and of sounds, and even variety of tone. It is 
 further obvious, and is to be noted as requiring careful consi- 
 deration hereafter, that a very large demand is made upon 
 intelligence, if there is to be even an approximation in actual 
 use of the organs, to the possibilities for which they are adapted. 
 And in this connection, as affording further illustration of the 
 demand upon intelligence, it is to be remarked that each one 
 of these terminal organs, by reason of its extreme sensitiveness, 
 is liable to be acted upon by mechanical and other influences 
 different from those for which it is expressly adapted. The 
 
78 THE RELA TIONS OF MIND AND BRAIN. {chap. 
 
 ordinary influence must gradually become, in all its ordinary 
 effects, the most familiar. In this way there comes to be a 
 distinction between ordinary and unusual or abnormal experi- 
 ence, the latter being regarded by us as illusory. Hence we 
 have come to speak of the delusions of the senses. There 
 is in reality no delusion. What occurs in a case so described 
 is merely an unfamiliar experience, which we are prone to 
 interpret according to ordinary experience. Doing this, we do, 
 indeed, delude ourselves, though, not unnaturally, we speak of 
 the "delusions of the senses." In this relation, it becomes 
 once more obvious that the organs of special sense make con- 
 stant and large demands on intelligence for their normal and 
 accurate use. 
 
iv-] LOCALISATION OF FUNCTIONS. 79 
 
 CHAPTER IV. 
 
 LOCALISATION OF FUNCTIONS IN DISTINCT PORTIONS OF THE BRAIN. 
 
 The general characteristics of the nerve system as now before 
 us are these, — that the brain is divided into two hemispheres, 
 distinct from each other, yet closely connected ; that over all 
 parts of our body there are double lines of communication with 
 the centre, the one set of fibres being sensory, the other motor ; 
 and that, as a rule, these two lines cross from the one side of 
 the brain to the opposite side of the body, making the left 
 hemisphere the centre for the right side of the body, and the 
 right hemisphere the centre for the left side of the body. 
 
 In attempting to reason from the susceptibilities and acti- 
 vities of the nerve system to the facts of experience, it is 
 obvious that great help must be rendered if it should prove 
 possible by advance of physiology to determine the functions 
 of the several convolutions of the cortex or grey matter of the 
 brain, as we have had determined the functions of the two 
 orders of nerves, with the special functions of the pairs of 
 cranial and of spinal nerves. This question as. to the functions 
 of the several divisions of the cortex is accordingly the one 
 upon which the greatest amount of time and labour has for 
 some time been expended by those engaged with investigations 
 concerning the nerve system. This field of research had been 
 clearly indicated by the previous stages of discovery. These 
 had been reached by advancing from without towards the 
 centre. First Haller pointed out that the irritability or con- 
 tractility of muscular fibre does not depend on its nerves. 1 
 From 1821 onwards to 1835, Bell presented at intervals to 
 the Eoyal Society the results of his investigations, in which 
 at length he clearly made out the distinction between " nerves 
 1 Haller's EUmenta, Physiologhe, Lausanne, 1762. 
 
80 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 of motion and of sensation." 1 Marshall Hall 2 advanced to the 
 determination of reflex action as characteristic of certain por- 
 tions of the nerve system, in contrast with voluntary action. 
 He showed that, besides voluntary action, there are amongst 
 involuntary actions not only those connected with breathing, 
 nutrition, and the various secretions of the body, but also reflex 
 actions, which are produced by means of a stimulating influence 
 coming from the extremity, and there giving rise to a respon- 
 sive or reflected activity. In this relation it was shown that 
 the portion of the subordinate nerve centres {Medulla) lying 
 nearest to the spinal cord, is of itself a centre for reflex action, 
 irrespective of the action of the Brain Proper. Thus the way 
 was opened for a more deliberate consideration of the functions 
 of the superior divisions of the central organ, and specially of 
 the Brain itself. Through a long series of difficult and delicate 
 investigations, to which references will be made as I proceed, 
 we have been brought at length to a full discussion of the 
 question as to the possibility of localising functions in distinct 
 portions of the brain. 
 
 In all countries the attention of skilled physiologists has for 
 a considerable time been directed to this subject. The interest 
 in it was stimulated and guided by pathological observations, 
 more especially those which connected paralysis of certain por- 
 tions of the body, and so-called " mental diseases," with lesions 
 in the brain, which were disclosed after the death of the 
 sufferers. The homology of brain structure recognised up the 
 whole scale of animal life, and strikingly illustrated by the 
 study of the development of the embryo of different orders of 
 animals, led to a new line of observation in comparative phy- 
 siology. The question was raised as to analogies of function 
 in the brains of the higher orders of animals, and in the human 
 brain. The use of anaesthetics for relief of suffering under 
 
 1 The Nervous System (collected papers), by Sir Charles Bell, Professor of 
 Surgery, University of Edinburgh. 
 
 2 First in 1832, in a paper on the " Reflex Function of the Medulla," after- 
 wards in a second memoir on " the Excito-motor System of Nerves," and 
 finally in a " New Memoir on the Nervous system " (1843). Dr. Hall was 
 closely followed in support of the same position by Professor Milller of 
 Berlin, Handbuch der Physiologie, 1833, — translated by Baly, 1838. 
 
IV.] 
 
 LOCALISATION OF FUNCTIONS. 
 
 81 
 
 severe surgical operations introduced the possibility of painless 
 operation upon living animals, with the view of ascertaining 
 the laws of functional activity in their brain, thereby guiding 
 to more definite conclusions as to the action of the human 
 brain. Previously, any insight which could be obtained was 
 dependent on rare cases of accident, or the terrible experience 
 of the surgeon and physician in the rear of the battle-field, or 
 in the military hospital near the scene of " action." Cases had 
 from time to time come under observation in which a consider- 
 able portion of the skull had been carried away without injury 
 'to the brain, and in such cases it was seen that, after nourish- 
 ment had been given, the flush of an increased blood supply 
 passed over the brain. But of necessity very little insight 
 could be obtained, in such cases, as to the functions of the 
 brain itself. 
 
 Now, however, we are in possession of a large mass of re- 
 corded observations concerning the action of the brain in the 
 case of a variety of animals under the influence of anaesthetics. 
 The circumstance that the 
 nerves can be readily excited 
 by electricity suggested the 
 possibility of experiment on 
 the brain by this agent. Tor 
 a time it was maintained that 
 the brain is not sensitive to 
 electric influence. But the pos- 
 sibility of electric stimulation 
 has now been clearly esta- 
 blished, and amply illustrated. 
 In 1870, Fritsch and Hitzig, 
 as the result of conjoint expe- 
 riments on the brain of the 
 dog, announced the electric 
 excitability of the brain, and 
 the identification of certain 
 motor areas in the cortex. 1 
 Fig. 21 illustrates these experi- 
 ments : — The five points marked were indicated as centres for 
 1 Du Bois-Reymond and Reichert's Archiv., 1870, p. 300. 
 F 
 
 Fig. 21.— UPPER SURFACE OF THE 
 BRAIN OF THE DOG, ILLUSTRATING 
 EXPERIMENTS OF FRITSCH AND 
 HITZIG. 
 
 {From Dr. Ferrier's Functions of the Brain.) 
 
82 THE RELA TIONS OF MIND AND BRAIN. [chap. 
 
 the following movements : — A, Movement of the neck ; +*, of 
 the fore limb ; +, rotation of limb ; %%, movement of hind 
 leg ; q of muscles of the face. 
 
 In 1873 Dr. Ferrier, Professor of Forensic Medicine in King's 
 College, London, submitted the results of a long series of 
 careful experiments on the brains of a considerable variety of 
 animals, by means of which he mapped out the brain to a 
 much larger extent than his predecessors had done. 1 Hitzig 
 prosecuted a further course of experiments, the results of 
 which were published in 1873. 2 The conclusions reached 
 by those investigations were in general harmony, differing 
 only in this, that Ferrier fixed a more numerous set of centres, 
 and often assigned to them a wider area. The accuracy 
 of Ferrier's experiments was keenly contested by a large 
 number of critics, but the result has been a general admission 
 of their reliability, while there continues much diversity of 
 opinion as to the inferences which they warrant. Investiga- 
 tions instituted by a Committee of the New York Society of 
 Neurology and Electrology, which included Drs. Dalton, Arnold, 
 Beard, Flint, and Masson, involving a repetition of experiments 
 from 10 to 40 times, confirmed the conclusions reached by 
 Hitzig and Ferrier. 3 The same result followed from the experi- 
 ments of MM. Carville and Duret in Paris during the years 
 1 874-5.* 
 
 By the kindness of Dr. Ferrier I have obtained the use of 
 several of the figures given in his work, which have the areas 
 of stimulation marked upon them. With the aid of these, I 
 shall endeavour to trace in brief outline his investigations as to 
 the localisation of functions in the brain. The problem raised 
 may be stated thus : — Can different functions be localised in 
 
 ^ 1 These results were first published in the West Biding Asylum Reports, 
 vol. iii., 1873, and were afterwards given in an independent and elaborated 
 form, Functions of the Brain, 1876. 
 
 2 Du Bois-Reymond and Reichert's Arckiv., 1873, 393. 
 
 3 New York Medical Journal, March 1875, p. 225. 
 
 4 Archives de Physiologie, 1875, vol. ii. For the history of these experi- 
 ments and criticisms I am indebted mainly to three very valuable papers in 
 the Journal of Anatomy and Physiology, vol. xii., by Dr. W. J. Dodds, assist- 
 ant -to Professor Rutherford in the Physiological Laboratory of Edinburgh 
 University. 
 
iv.] LOCALISATION OF FUNCTIONS. 83 
 
 distinct portions of the convoluted grey matter of the brain ? 
 Or, otherwise expressed, can distinct areas of the cortex be 
 marked out to which distinct functions can be proved to 
 belong ? Dr. Ferrier puts the alternative in the following 
 form : — " Whether the cerebrum, as a whole, and in each and 
 every part, contains within itself, in some mysterious manner 
 inexplicable by experimental research, the possibilities of every 
 variety of mental activity, or whether certain parts of the brain 
 have determinate functions." * Dr. Terrier decides in favour of 
 localisation of functions, giving a detailed account of the experi- 
 ments on which he relies for its vindication. The agency em- 
 ployed by him is the Faradic current of electricity ; that is, the 
 interrupted current of an induction-coil, admitting of increase or 
 diminution at pleasure. While referring specially in this rela- 
 tion to electric stimulation, it is needful to bear in mind that 
 nerves may be stimulated by a variety of agents, such as pres- 
 sure or friction, variations of temperature, and chemical appli- 
 ances. Experiments by means of chemical stimulation have 
 been made by Nothnagel and others, but the results have not 
 proved so distinct and reliable as those obtained by electric 
 stimulation. Probably the electric stimulus is more nearly 
 analogous to the action of nerve force. Yet the transmission of 
 nerve force along the nerve line is so dependent upon vital rela- 
 tion with the nerve centre, that the transmission is completely 
 interrupted if the nerve line be cut, whereas the cutting of a 
 wire will not hinder the progress of the electric current, if 
 the two ends be placed in contact. Thus experiment by 
 electric stimulation does not imply a complete analogy between 
 the agent employed and the nerve force generated in the 
 brain. 
 
 Dr. Ferrier's experiments extend to the brains of fishes, frogs, 
 pigeons, rats, rabbits, guinea-pigs, cats, dogs, jackals, and 
 monkeys. They thus imply tests applicable to a considerable 
 range on the scale of animal life. As, however, it is needful to 
 limit this narrative, I shall restrict attention to results attained 
 in the case of the dog and of the monkey. The mode of 
 experiment is to place the animal under the influence of such an 
 anaesthetic as chloroform ; thereafter to expose the surface of 
 1 Functions of the. Brain, p. 124. 
 
84 
 
 THE RELA TIONS OF MIND AND BRAIN. 
 
 [CHAP. 
 
 the brain ; then to apply the electrodes to a point on the brain, 
 noting the effect, and repeating experiments, until it appears 
 beyond doubt that a uniform result has been secured. The 
 brain of the monkey is taken as the test, being allied in struc- 
 ture to the human brain. 
 
 TSL 
 
 Fin. 22.-BRAIN OP THE MONKEY— LEFT HEMISPHERE 
 
 (natural size), 
 
 (From Dr. Ferrier's functions oftlie Brain.) 
 
 Restricting attention to the single capital letters outside the 
 figure, the four main divisions of this brain are easily seen. 
 First, there is the great fissure from below, running upwards 
 with inclination towards the rear, dividing the organ into a 
 front part and a back part. This is marked A, and is known 
 as the Fissure of Sylvius. Second, there is the fissure coming 
 from above downwards, showing an inclination towards the 
 Fissure of Sylvius, constituting the right boundary of a frontal 
 division of the brain, and the left boundary of a middle division 
 belonging to the upper region of the brain. This is marked B, 
 and is known as the Fissure of Eolando. Third, there is a 
 fissure also coming from above, which terminates the middle 
 division in the iipper region, and is the left boundary of the 
 back region. This is marked C, and is named, by combination 
 of the names of the two regions it separates, the Parieto-Occi- 
 pital Fissure. These three fissures mark out the four great 
 divisions or lobes of the brain ; — to the front of the first and 
 second is the Frontal lobe ; between the second and third is the 
 
lv -l LOCALISATION OF FUNCTIONS. 85 
 
 Middle lobe, lying in the upper region, and called the Parietal 
 lobe ; behind the third is the posterior lobe, known as the Occi- 
 pital ; and in the lower region, behind the first fissure, is the 
 middle division on the lower side of the organ, which is known 
 as the Temporo-Sphenoidal lobe. There are thus four divisions, 
 one to the front, one to the back, and two in the middle, the 
 one upper, the other lower. Keeping still to the outside of the 
 figure, and taking now the double capitals, the front lobe is 
 marked FL, the back lobe OL, the upper middle PL, the lower 
 middle TSL. These are, as we have already seen, the four lobes 
 of the human brain. The two brains are in very close analogy, 
 with this single exception that the third fissure, which is 
 the boundary of the occipital region, is not so marked on 
 the surface of the human brain. The small italics outside 
 the figure indicate minor furrows or sulci in the frontal 
 region, one the superior, sf; the other inferior, if; and the 
 third anterior to the parietal, ap. Similar use is made of 
 small italics within the figure. Within the front lobe, 1, 2, 
 and 3, after F, indicate the upper, middle, and under con- 
 volutions ; AF, the ascending frontal convolution. In the 
 middle upper lobe (parietal) there are AP the ascending, PPL 
 posterior, and AG the angular Gyrus. The figures 1, 2, 3, 
 after and T, indicate upper, middle, and lower convolutions 
 in the two remaining lobes. In addition to these four lobes 
 there is in the brain of the monkey, as in the human brain, 
 the central lobe (Island of Eeil), covered up by the folds of 
 the Sylvian fissure. 
 
 With this map of the brain of the monkey before us, it 
 is manifest that the theory of localisation of functions in the 
 cortex of the brain encounters great preliminary difficulties 
 on account of the unbroken continuity of the several parts 
 of the organ. The various divisions or lobes of the brain 
 are not only in close proximity, but are actually united or 
 continuous. The same thing holds true when we turn atten- 
 tion to the convolutions of each lobe, for in no case is 
 there isolation of one from the others, but in all cases com- 
 munication. These considerations clearly favour the hypo- 
 thesis that the organ may in all cases act as a whole, while 
 it has undoubtedly its distinct points of established relation 
 
86 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 with the several parts of the body. There is this additional 
 perplexity for the hypothesis of localisation of function, that 
 inter-communication of all the parts suggests the possibility 
 of diffusion of influence on application of any such stimu- 
 lating agency as electricity. At the same time, the results of 
 Dr. Ferrier's experiments are sufficiently definite, and have 
 been amply tested. Whatever dispute there may be as to 
 their interpretation, the results themselves are beyond doubt. 
 The nature of these results will appear from the following 
 figure : — 
 
 io. 23.— BRAIN OF THE MONKEY, LEFT HEMISPHERE, SHOWING CENTRES OF 
 STIMULATION INDICATED BY FERRIER'S EXPERIMENTS. 
 
 (From Ferrier's Functions of the Brain.) 
 
 The exact position of several of these centres will be better 
 understood by reference to figure 24 (p. 87), showing the upper 
 surface of the hemispheres. 
 
 The first glance at these figures shows that the centres iden- 
 tified are chiefly clustered upon the central portion of the organ. 
 This does not arise from the circumstance that Dr. Terrier 
 restricted his attention to the area indicated, for his experiments 
 ranged over the entire brain ; but the unmarked portions are 
 those which were experimented upon by application of the 
 electrodes without any consequent movement, or evidence of 
 influence being communicated. These unmapped portions of 
 the brain, therefore, raise a distinct problem, which is not 
 likely to prove easy of solution. To this problem I shall turn 
 
IV.] 
 
 LOCALISATION OF FUNCTIONS. 
 
 87 
 
 Front. 
 
 attention after having given some account of the centres 
 
 which are marked, and the 
 
 testimony thereby adduced 
 
 as to the functions of the 
 
 brain. 
 
 Instead of taking the num- 
 bers in order from 1 to 15 (fig. 
 23), some advantage will be 
 gained by selecting them in 
 groups, according to the por- 
 tions of the body influenced. 
 
 Interest concentrates first 
 on Nos. 1 and 5. These 
 indicate centres which are 
 both on the summit of the 
 hemisphere, next the longi- 
 tudinal fissure, the one being 
 towards the back of the 
 brain, the other towards the 
 front. The application of F '°- 24. -upper surface of the hemi- 
 electric stimulation to No. 1 SPHERES 0F THB M0NKBY - 
 
 ,. n j , . j, (From Ferrier's Functions of the Brain.) 
 
 is followed by movement of 
 
 the hind limb ; to ISTo. 5 by movement of the fore limb, each 
 limb set in motion being the one on the opposite side of the 
 body from the hemisphere under observation. The two move- 
 ments are practically identical, the one being " advance of the 
 opposite hind limb, as in walking ;" the other advance of the 
 opposite fore limb, or, as Dr. Ferrier states it, " extension for- 
 ward of the opposite arm and hand, as if to reach or touch some- 
 thing in front." 1 The account of the second movement seems 
 to embrace more than that of the first. This is readily 
 explained by the consideration that the monkey accomplishes 
 more by the fore paw than by the hind. The observer 
 gives a reference to the purpose of the movement, " to reach 
 or touch," but, as movements merely, the two are the same, the 
 difference being only that in the one case it is a hind limb that 
 is moved, in the other a fore limb. If then the theory of 
 distinct motor centres is accepted, these two circles determine 
 1 Functions of the Brain, p. 143. 
 
88 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 the forward movement of the two limbs on the opposite side of 
 the body. If the theoiy be doubted, and if only the visible 
 results of actual experiment be accepted, still it is granted that 
 the brain as a whole does, by stimulation at these points, 
 control the movement of the limbs, so as to determine their 
 extension or advance from a present situation to a situation in 
 front. Whether the centres alone exercise the function of 
 determining forward movement in a particular limb of the 
 body, or the whole organ determines such movement by con- 
 centrated influence at these points, does not seriously affect 
 the view to be taken of the brain's relations to muscular 
 movements. And as the matter in doubt is one which may 
 prove difficult, or even impossible to settle, it is well to remark 
 the conclusion involved in either alternative. There is so 
 much of the area of the brain directly connected with so much 
 of the muscular system. There are four distinct centres for the 
 motor nerves which control the four limbs. And further, it 
 is shown by direct experiment, in harmony with anatomical 
 evidence as to the distribution of the nerve fibres, that each 
 hemisphere is concerned with the control of the nerves which 
 pass to the opposite side of the body. These conclusions drawn 
 from the first examples of electric stimulation here selected 
 will be found to be supported by the examples which follow. 
 
 I take next the additional centres concerned with the hind 
 leg and the region of the body closely related. In this group 
 there are included Nos. 2 and 3, which both lie forward from 
 No. 1. No. 2 is a large centre, with a single exception the largest 
 described on the figure. Its proportions will be best seen by 
 looking at the representation of the upper surface of the brain 
 (fig. 2i). Its size is in part accounted for by the series of 
 movements attributed to it. These are " complex movements of 
 the thigh, leg, and foot, with adapted movements of the trunk, 
 by which the foot is brought to the middle line of the body, 
 as when the animal grasps anything with its foot, or scratches 
 its chest or abdomen." 1 These movements are such as to 
 bring into exercise a large number of muscles and nerve fibres ; 
 but as these commonly perform their part in union, there is 
 nothing surprising in the circumstance that, after the centre 
 1 Functions of the Brain, p. 141. 
 
iv.] LOCALISATION OF FUNCTIONS. 89 
 
 had been determined, subdivision of it had been found imprac- 
 ticable. The same remark applies to the statement made by 
 Dr. Ferrier as to No. 3, which is marked as the centre for 
 " movements of the tail, generally associated with some of the 
 movements described under the last." He says, " I have not 
 been able to dissociate the two from each other completely." 
 Certainly nothing is more familiar in common observation 
 than the movement of the tail of the animal along with the 
 movement of the hind limb. Now if these two centres be 
 admitted as experimentally determined, whether under a 
 theory of localised function, or of general action of the 
 brain, a large part, and organically a very prominent and 
 important part, of the organ, is connected with the complex 
 movements involved in the range of action possible to the hind 
 leg of the monkey. And here it may be needful to remark 
 that the species of monkey operated upon was the Macacque, 
 an order of monkey whose agile movements differ considerably 
 from those of the large apes, such as the orang, chimpanzee, or 
 gorilla. The special feature of the movement, as described by 
 Dr. Ferrier, is this : movement " as when the animal grasps 
 anything with its foot." Grasping with the foot, more particu- 
 larly with the hind foot, as in this case, is not a common exer- 
 cise with animals. There seems, therefore, reason for considering 
 it something special. It is the exercise which we attribute 
 to our hand, and which we should not think of referring to our 
 foot. It is the movement of the foot of the bird as it alights 
 on a branch, and is well illustrated by the action of the parrot 
 in grasping a gooseberry or a plum in order to eat it. "While it 
 is tlms a common use of the foot with the bird, it is otherwise 
 with the quadrupeds, being impossible to many animals, such 
 as the horse or ox ; and where it is to some extent possible 
 with quadrupeds, it is restricted to the action of the fore paw, 
 as it expands and closes over an object to be held in position. 
 This is illustrated by the cat and dog, and generally by beasts 
 of prey ; but even with them it is not the exercise of the hind 
 foot, except in so far as the action is exemplified in climbing. 
 But climbing involves the action of all the muscles concerned 
 in locomotion, and of all four limbs at once ; so that grasping 
 by the hind foot singly can hardly be attributed to any animal 
 
go THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 except the monkey, which not only is habitually engaged in 
 climbing, but makes large use of the hind paw, while hanging 
 on with the hand or fore paw. The great toe on the hind foot of 
 the monkey always acts the part of a thumb. It fulfils on the foot 
 the function of the thumb in the human hand. The foot of the 
 monkey, therefore, does not in its method of use resemble the foot 
 of man, but rather the hand of man, save that it is naturally 
 turned downwards. In illustration of its action I give the fol- 
 lowing statement by Francis T. Buckland: — "His great toe 
 takes the office of a thumb, and is of the greatest use to him in 
 holding on to branches during the act of climbing. . . . Watch 
 a monkey go up a pole ; you will see he places his hind feet 
 on the surface of the pole at a considerable angle to the 
 body (which his anatomy enables him to do), and thus he 
 ascends." 1 In confirmation of the view that this is an action 
 of the foot peculiar to the monkey, it is striking to find 
 that No. 2 disappears from the figures showing the results of 
 electric stimulation on the brain of the cat, dog, and jackal, 
 while No. 3, concerned with movement of the tail, appears in 
 all. 2 This will be seen by reference to the figures of the brain 
 of the cat and dog (figs. 31 and 32, pp. 132, 134). The facts 
 connected with the two centres here taken together seem to 
 warrant these two conclusions : that any form of activity pecu- 
 liar to one animal, or to a limited group of animals, in contrast 
 with others, will have a special portion of the brain connected 
 with the regulation of such movement ; and when any move- 
 ment is common to a large series of animals, there will be a 
 common centre for producing the movement which is equally 
 habitual with all. These two conclusions are upheld by 
 experiment, whether the doctrine of localisation of function 
 be accepted or rejected. They are in truth only an extended 
 application of the general conclusion reached while considering 
 the two centres first named ; for if there be connected with the 
 nerves and muscles some definite part of the brain, by means of 
 which a distinct movement is accomplished, it will follow that 
 there must be a special portion of the brain for a move- 
 ment which is peculiar to certain animals. The truth of this 
 
 1 Curiosities of Natural History ; third series, vol. ii. p. 153. 
 
 2 Functions, pp. 149, 152, 154. 
 
iv.] LOCALISATION OF FUNCTIONS. 91 
 
 is established by the clear and uniform testimony of com- 
 parative anatomy and physiology. 
 
 There is one additional point connected with the large centre, 
 No. 2, deserving consideration. This centre not only covers part 
 of two convolutions, but in doing so occupies a place in two 
 lobes, being partly in the frontal, and partly in the upper 
 middle (parietal) lobe. By this circumstance we are reminded 
 that there is no real severance of the lobes. "Whatever reference 
 may be made to sulci and fissures, as convenient boundary lines 
 for marking certain divisions of the organ, it is needful to have 
 it kept constantly in mind that the grey matter is in reality 
 continuous. That there is significance in the subdivision of 
 the brain into lobes there can be no doubt, but not such as to 
 imply a complete severance of functional activity in the parts. 
 
 I take now, as closely connected with some of the conclusions 
 just reached, the results indicated by the letters a, b, c, d, placed 
 on the ascending convolution of the upper-middle lobe (parietal), 
 along with results connected with the centres numbered 4 and 
 5 (fig. 23). The result of application of the electrodes to the 
 points a, b, c, 'd, was found to be " individual and combined 
 movements of the fingers and wrist, ending in clenching of 
 the fist." 1 Dr. Terrier states that he found it impossible to 
 identify centres for the extension and bending of the separate 
 fingers, though all the movements concerned in grasping objects 
 were produced by excitation of these centres. The movements 
 were those of the arm on the opposite side of the body. Ex- 
 periment on the centre marked No. 4 was followed by move- 
 ment of the opposite arm, which was first thrown forward, and 
 then brought back again, " the palm of the hand being directed 
 backwards," in a manner " resembling a swimming movement." 
 The centre, No. 5, when stimulated, occasioned " extension 
 forward of the opposite arm and hand, as if to reach or touch 
 something in front." Looking now at the centres Nos. 4 
 and 5, along with those marked a, b, c, d, it is obvious that 
 these six are closely connected. No. 5 provides for the 
 forward movement of the right arm; No. 4 for the drawing 
 back of the same arm ; while the centres a, b, c, d, collectively, 
 provide for action from the wrist forwards, that is, move- 
 1 Functions, p. 143. 
 
92 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 ment of the whole hand and of the several fingers. In most 
 cases, when the centres a, b, c, d are in action, the centres, 
 Nos. 5 and 4, will also be in action, for the arm is com- 
 monly thrown forward when anything is to be grasped, whether 
 an article of food or a branch overhead, 1 and it is drawn back 
 again with the food or when the branch is let go. In the 
 close relation of Nos. 5 and 4 with the centres a, b, c, d, we 
 have a further illustration of the fact that several centres must 
 very commonly act together. In this fact there also appears 
 something to favour the view that the brain acts as a whole, 
 concentrating its energy on definite points according to the 
 nature of the physical exercise accomplished. When it is 
 further noticed that No. 4 like No. 2 extends over part 
 of two lobes, being partly in the frontal lobe, partly in the 
 upper-middle (parietal), there seems to be additional evidence 
 favouring the conclusion that the brain acts> as a whole. Leav- 
 ing this, however, to remain one of the unsettled points, the 
 clear result of these experiments is that different centres fre- 
 quently act in unison (vide p. 57). 
 
 It seems singular that the centre for the movement of the 
 tail, No. 3, should be found between 5 and 4. In the 
 differently arranged convolutions of the dog, No. 3 stands 
 quite clear of 4 and 5. As, however, in the human brain, 
 No. 3 falls out, Nos. 4 and 5 may be contiguous, and each 
 have more space. 
 
 The chief interest at this point, however, gathers around the 
 centres marked a, b, c, d, which together occupy almost an 
 entire convolution of the upper-middle lobe. These, as the 
 centres concerned with the movement of the hand, and several 
 joints of the fingers, must be peculiar to the monkey among 
 the lower animals, as the monkey tribe is the only one having a 
 hand with jointed fingers, analogous to the hand of man. Accord- 
 ingly these centres are wanting in the brain of the cat, the dog, 
 and the jackal, as experimented upon by Dr. Terrier, with this 
 exception that in the cat (fig. 31, p. 132) there is the first of the 
 series marked (a), which indicates the clutching or closing of the 
 
 1 There is humour in the suggestion that the monkey should be re- 
 garded as intellectually equal with man, because it grasps " the higher 
 branches." 
 
IV.] LOCALISATION OF FUNCTIONS. 93 
 
 paw, as when the cat plays with a mouse. As the joints, muscles, 
 and nerves in the hand and fingers of the monkey make provi- 
 sion for a great variety of movements which are altogether im- 
 possible when the terminal organ is simpler in structure, there 
 must be a proportionally greater number of connecting lines 
 between the extremity and the nerve centre than can exist in 
 the brain of lower forms of animal life. The possibility of 
 exciting these centres by electric stimulation, so as to induce 
 movement of all the joints of the fingers, illustrates the truth, 
 clearly implied in the results of anatomical science, that each 
 mechanical provision for movement is connected with a distinct 
 part of the nerve centre. The impossibility of finding any 
 such centres in the brain of other animals was inevitable on the 
 hypothesis. The speciality in the brain of the cat is con- 
 firmatory of the inference from the brain of the monkey. The 
 general conclusion to which we are here guided is that the 
 brain becomes more complex in arrangement proportionately to 
 the mechanical complexity of the body which it governs. Com- 
 paring together the experiments on the brain of the monkey, 
 jackal, dog, and cat, there are in all four cases definite centres, 
 numbered 5 and 4, for the common movements forward and 
 backward of the fore limb on the right side of the body. But 
 in the brain of the monkey there are special centres {a, b, c, d,) 
 for the movement of the fingers, as well as the hand, which are 
 not to be found in the brain of the other animals named. 
 
 In order to complete the views of analogy and difference 
 thus obtained, there is one element in the description of the 
 movement resulting from stimulation of the common centre, 
 No. 4, which deserves consideration. Besides the drawing 
 back of the opposite arm, Dr. Ferrier remarks that the back- 
 ward movement of the arm was effected with the palm of the 
 hand turned backwards, the action " resembling a swimming 
 movement." This is in more obvious analogy with the human 
 hand, and suggests a contrast with the act of dropping the 
 hand when the grasp of an object is relaxed, or the bringing 
 back of the hand when it is full. But it more resembles a 
 purposive movement, such as the latter, than a mere cessation of 
 exertion as in the former. The stimulation seems to have 
 resulted in an action for a definite end. The movement is of 
 
94 , THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 the kind which would be executed if the right hand were swept 
 back to take hold of a branch somewhat below, while the left 
 was thrown forward to catch one overhead. If when accom- 
 plished under electric stimulation this movement of the right 
 hand suggests the act of swimming, it is to be remarked, as 
 bearing on the analogies of movement, that the progress of 
 the animal from tree to tree, by aid of the swaying branches, 
 must be analogous to an act of swimming. The movement 
 involved is not one of relaxation, but of tension for a definite 
 end. 
 
 The centre marked No. 6 when stimulated led to bending 
 of the arm, and elevation of the hand to the mouth. This 
 is a motion familiar with the monkey, so that ^the communi- 
 cation between the brain and the arm for this movement must 
 be nearly as well established as the communication for ordi- 
 nary exercise in walking in the case of the dog. The monkey 
 clutches its food in its forepaws, and so brings it to its 
 mouth. The act of the dog in eating is entirely different, 
 involving sometimes only lapping with the tongue, at other 
 times clutching its food so as to hold it firmly on the ground, 
 while the head is lowered, that the teeth may tear flesh or 
 crush a bone. It is, therefore, a confirmation of the conclusion 
 already adduced, when we find that no place in the brain of 
 the dog can be assigned to No. 6 on the brain of the monkey. 
 There may naturally be some surprise that it has not been 
 found on the brain of the cat, since we are all familiar with 
 that movement of the cat's paw when it is engaged " washing 
 its face," as is said. But the movement so described is so 
 analogous to other movements common with the cat, that what 
 we are in search of here may be nothing more than an adapta- 
 tion of No. 5, under the influence of a special phase of sensi- 
 bility. 
 
 The next group of centres includes Nos. 7, 8, 9, 10, 11. 
 These are situated partly on the frontal lobe, partly on the 
 upper middle, a combination which is confirmatory of what has 
 already been said as to co-operation of different lobes of the 
 brain. These five centres are all concerned with movements 
 of the mouth. Electric excitation of No. 7 leads to action of 
 the muscles of the face, so as to draw back and elevate 
 
IV.] LOCALISATION OF FUNCTIONS. 95 
 
 the angle of the mouth ; No. 8 elevation of the outer wall of 
 the nose and of the upper lip, with depression of under lip, 
 thus exposing the teeth; 9 and 10 opening of the mouth, the 
 former involving the act of protruding the tongue, the latter 
 the act of withdrawing it ; 11," retraction of the opposite angle 
 of the mouth." 
 
 No. 1 2 is a large centre quite .to the front of the brain, and 
 covering a portion of the two upper divisions of the frontal 
 lobe. This is concerned with the movement of the eyes and 
 head ; while away towards the back portion of the upper-middle 
 lobe are situated the six centres numbered 13 and 13', the 
 whole of which are concerned with the movements of the eyes. 
 Under electric excitation, No. 1 2, situated far forward, occasions 
 a complex order of movements; "the eyes open widely, the 
 pupils dilate, the head and eyes turn towards the opposite 
 side." When the three centres numbered 13 are stimulated, 
 there is movement of the eyes towards the opposite side, with 
 an upward direction ; when the influence is directed on any one 
 of the three centres numbered 13', there is movement of the 
 eyes towards the opposite side, with a downward direction. 
 With stimulus of any one of these centres, the pupil contracts, 
 and there is a tendency to close the eyelid, as if under a 
 strong light. The wide separation of the large centre numbered 
 12, from the six centres numbered 13, while all are closely 
 related in respect of the results of their action, is one of the 
 features presented by these experiments deserving special con- 
 sideration, as appearing to favour the conclusion that there 
 is within the organ a most elaborate system for combining 
 different portions of the brain. In this case also there is 
 evidence to favour the opinion that the brain acts as a whole, 
 for it seems warrantable to conclude that 12 and 13 must 
 often co-operate ; and, if they do, it is a natural inference in 
 the case, that the whole brain is concerned in the combination 
 of these movements. 
 
 A further example of associated action is given by stimulation 
 of the centre numbered 14, the situation of which carries our 
 attention for the first time to the lower-middle lobe (temporo- 
 sphenoidal). This when stimulated leads primarily to " pricking 
 of the opposite ear," but this is combined with turning of the 
 
96 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 head and eyes to the opposite side, while the pupils are widely 
 dilated. The combination involved in the action of this centre 
 clearly points to a movement of the ear consequent upon some 
 impression made through the eye, and probably conjointly with 
 an impression made upon the ear. If this explanation of 
 the action be regarded as the natural one, this portion of 
 the experiments tends to support the view of united brain 
 action. 
 
 The centre numbered 15 carries the attention to a region 
 altogether apart from that on which the preceding centres have 
 been found to gather. This is situated quite on the lower 
 portion of the under-middle lobe (temporo-sphenoidal), just as 
 it turns towards the base of the brain. This centre, concerned 
 as it is with the nose, has some degree of association with 
 No. 8. When the electrode is applied to No. 15, there is a 
 twisting of " the lip and nostril on the same side." This move- 
 ment so affects the organ of smell, " as to cause a partial closure 
 of the nostril, as when a pungent odour is applied." 1 Exactly 
 similar results are obtained by experiment upon the same spot 
 in the brain of the dog, cat, and rabbit. The apparent associa- 
 tion between the movements produced and the influence of a 
 powerful odour is confirmed by direct external experiment, 
 showing that the movement here produced is beyond question 
 excito-motor. "Similar reaction is produced by the direct 
 application to the nostril of a powerful or disagreeable odour." 2 
 The reflex nature of this movement being thus determined, the 
 situation of the centre by stimulation of which it is produced 
 is matter of great interest, when we take into account the fact 
 that an analogous centre is found in the dog, cat, and rabbit. 
 In these three animals the olfactory nerve, with large olfactory 
 bulb in front of the brain, is conspicuous. Illustration of this 
 will be found by reference to the three appropriate figures in 
 next chapter, pp. 130-134. Now this centre, No. 15, severed 
 as it is from the other centres which cluster much higher up, is 
 situated in close connection with the olfactory tract. In this 
 way, it presents an important illustration of close local relation 
 within the brain of the parts which provide for sensibility, and 
 consequent reflex activity. This circumstance in itself affords 
 1 Functions, p. 144. 2 Jb. \i. 184. 
 
IV.] LOCALISATION OF FUNCTIONS. 97 
 
 strong confirmatory testimony in support of the whole series of 
 experiments. Additional evidence for the accuracy of the con- 
 nection indicated between the centres in the brain and the 
 portions of the body controlled by them, is found in the one 
 fact that each branch of the olfactory tract runs directly to its 
 centre on the same side of the brain, and does not cross to the 
 other hemisphere, taken with this other fact, that the result 
 of stimulation of centre 15 in the left hemisphere was visible 
 in the movement of the nostril on the same, side. This is at 
 once seen by comparing the record as to this centre in the 
 brain of the dog, 1 and on that of the cat, 2 with that of the 
 monkey here adduced. 3 In the case of the rabbit, excitement 
 of 15 on the left hemisphere commonly produced twisting of 
 the nostrils on both sides. 4. But the brain of the rabbit is a 
 smooth one, without convolutions, and the olfactory tract is 
 relatively larger in proportion to the brain. It seems, there- 
 fore, the more likely that a strong impression made on a point 
 in one side of the brain would induce action in both nostrils, 
 on account of the close union subsisting between the two 
 centres connected with the organ of smell in a brain of simple 
 construction such as that of the rabbit. 
 
 Having now taken a survey of the several centres definitely 
 marked on the brain of the monkey, it is desirable to notice in 
 addition the general conclusions to which these experiments 
 appear to point. These are two in number. 
 
 First. Under these experiments there is a large part of the 
 surface of the brain appropriated for the movements effected by 
 portions of the body. If the eye run along the surface of the 
 brain (fig. 24, p. 87), taking in the following, 1, 2, 5, thereafter 
 going down to 6, next turning back to take 4, and thereafter pass 
 down to include d, c, b, a — all these are involved in the move- 
 ments of the hind and fore limbs on the right side of the body. 
 If next, turning to the side view of the same hemisphere (fig. 23, 
 p. 86), we begin with 7, go down past 8 and 9 on the ascending 
 frontal lobe, and ton up to include 10 and 11, by which we 
 are brought to nearly the same level from which we started 
 on the ascending region of the upper-middle lobe, we find all 
 this division is appropriated for movements of the mouth and 
 1 Functions, p. 151. 2 lb. p. 156. 3 lb. p. 144. 4 lb. p. 158. 
 
 G 
 
98 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 tongue. Again, in seeking for movementa connected with 
 the use of the eyes, we include 12 (13, 13, 13) (13', 13', 13'). 
 Some limitation of these areas, it may be allowed, may yet 
 prove needful under the possible rectification of persistent 
 experiment ; but even if this prove true, to the extent of a 
 considerable modification, a high degree of importance must 
 attach to the general observation here adduced. 
 
 Second. The large unappropriated area in no way diminishes 
 the effect of the observation just made, but contributes to its 
 importance. This area embraces considerable portions of the 
 frontal lobe and the under-middle (temporo-sphenoidal), with the 
 whole of the back lobe, and the central lobe or island, hid under 
 the folds of the Sylvian fissure. Still, little short of one-half of 
 the superficial area is appropriated, and this includes much of 
 what is regarded as the most important part of the organ, 
 whether judged by external form or by internal structure. We 
 must consider, besides, how many forms of action are yet to be 
 accounted for by brain control of the muscular system, and also 
 what provision is made at the nerve centre for all the forms of 
 feeling possible through the whole order of sensory nerves. 
 There need not meanwhile be any question raised as to intel- 
 lectual exercise in addition, because, at the present stage of 
 inquiry, the other elements involved give sufficient importance 
 to the general consideration now before us. Something here 
 will depend upon the ultimate decision as to the interpreta- 
 tion of the centres marked out, whether they are to be regarded 
 as exclusively motor centres, or whether it may be supposed 
 that they are conjointly sensory and motor. The possibili- 
 ties of modification of result in this way must be carefully 
 allowed for ; but even with this proviso, it is impossible 
 to overlook the importance which attaches to the compara- 
 tive area of the appropriated and unappropriated divisions in 
 the brain of the monkey when placed under electric stimu- 
 lation. 
 
 I shall now shortly consider the results of electric stimula- 
 tion when applied to the brain of the dog, with the view of 
 comparing results in the two cases. In this way, some test is 
 obtained of the extent to which such stimulation may be 
 regarded as a reliable illustration of brain action; and addi- 
 
Iv -] LOCALISATION OF FUNCTIONS. 99 
 
 tional light is thrown upon the wider question of the relations 
 of brain function to the recognised characteristics of various 
 forms of animal life. 
 
 Fio. 25.— BRAIN OP THE DOG— LEFT HEMISPHERE. 
 (From Ferrier's Functions of the Brain.) 
 
 After the detailed account of results given in the former case, 
 it will be unnecessary to enter with the same minuteness upon 
 a description of what may be at once understood by reference 
 to the above figure. In order to facilitate comparison, Dr. 
 Ferrier continues to use the same number to represent the same 
 centre in the various examples selected. It is, therefore, simple 
 to read off his results. 
 
 Looking first at the general appearance of this brain, in com- 
 parison with that of the monkey, the attention is at once 
 arrested by the addition to the organ, which stretches along 
 underneath, and bulges out in front, marked 0. This is the 
 olfactory tract, with large olfactory bulb in front. This indi- 
 cates that a much larger influence is assigned to the organ of 
 smell in the life of a dog than in the life of a monkey. The 
 next marked feature in the comparison is the difference in the 
 arrangement of the convolutions. They are arranged more in 
 longitudinal form, stretching from front to back, with some 
 additional folds in front. If the eye be directed on the Sylvian 
 fissure, which is the grand dividing line in all convoluted 
 brains, and is marked by the line passing over the olfactory- 
 tract from A, it will appear that the convolutions are gathered 
 round this. The substance is first folded on this fissure ; next 
 
loo THE RELA TIONS OF MIND AND BRAIN. [chap. 
 
 it is doubled back and folded again round the line of the fissure, 
 with a proportionately wider circle ; and so a third time, but 
 with some trace of subdivision as it sweeps, round at the rear ; 
 and again a fourth time, coming from behind and running along 
 the surface. These are the four external convolutions of the dog's 
 brain, marked from above downwards I. II. III. IV. Just where 
 the upper convolution (I.) terminates in front, there appears a 
 second fissure, marked B, known as the concial or frontal sulcus 
 or fissure. Around this gathers a small group of frontal con- 
 volutions. 
 
 Comparing now the centres on this brain with those found 
 on the brain of the monkey, I shall take first the analogies, 
 indicating them in the same groups of circles as in the for- 
 mer case. Nos. 1 and 5 were taken as the first group, the 
 former indicating movement of the hind limb on the opposite 
 side, and the latter movement of the fore limb on that side. 
 These are both found here on one of the front foldings, and 
 much more closely together, the one being almost above the 
 other. No. 4 marked the movement in bringing back the fore 
 limb of the right side, and that is here just behind No. 5. No. 
 3, which marks the centre for movement of the tail, is found 
 here, but to the rear of No. 5, and on the uppermost external 
 convolution. The centres 7, 8, 9, 10, 11 were all found to be 
 concerned with the movements of the mouth and tongue, and 
 they are all here, except 10, the stimulation of which in the 
 monkey's brain was followed by withdrawal of the protruding 
 tongue, but in the case of the dog No. 9 was found to produce 
 the two movements assigned to 9 and 10 in the monkey's brain. 
 Something in this relation may be due to the fact that the dog 
 runs so much with its tongue out, that a larger and more 
 constant measure of nerve energy is directed towards this 
 exercise. This series of centres is here grouped in a manner 
 quite analogous to what was seen in the brain of the monkey, 
 passing round from one convolution to another. The special 
 feature here is that triple centres are found for 7 and 11, 
 and double centres for 8. No. 7 in the monkey is identified 
 as the centre for movement of the muscles belonging to 
 the mouth, and here it is the same. But when the descrip- 
 tions of resultant actions are compared, it is seen that, in the 
 
IV.] LOCALISATION OF FUNCTIONS. 101 
 
 case of the dog, there is reference to movement of the eyes and 
 closing of the eyelids, as was not done in the case of the 
 monkey. Besides, it is here remarked that both eyeballs are 
 seen to move, while it is the opposite eyelid which closes. All 
 this is in harmony with the recognised habits of the dog, in 
 contrast with those of the monkey. Any one who watches the 
 dog when engaged gnawing a bone, will perceive how naturally 
 he closes his eye while bringing the whole force of bone and 
 muscle to bear on his task. And, as it is impossible for the 
 right side of the mouth to be so engaged without so far exer- 
 cising the parts on the left side, and both eyes as a rule work 
 together, it is natural that both eyeballs be affected in the 
 manner here represented. This contrast between the dog and 
 monkey is confirmatory of what has been already said, that 
 diversity of muscidar movement in the case of distinct orders 
 of animals involves diversity in the structure of the brain. 
 From the cause just referred to, a wider range of action is 
 common to all movements belonging to the side of the face in 
 the dog than in the monkey, and by the association of con- 
 tiguous muscles and nerves it is easy to appreciate the circum- 
 stance noticed by Dr. Ferrier in connection with stimulation of 
 centre 1 1 — " On one or two occasions, I have observed the, ear on 
 the opposite side drawn forwards while the angle of the mouth 
 was retracted" (p. 150). 
 
 The centres numbered 12 and 13 in the case of the monkey 
 were those which were found to regulate movements of the 
 eyes; and the action produced by stimulation of the centres 
 thus marked in the brain of the dog are nearly identical. There 
 is an interesting coincidence in the relative situation of the two 
 numbers, 1 2 and 1 3, on the two figures. In both cases 1 2 is found 
 on the frontal region, while 1 3 is placed quite far back, behind 
 the centres for regulation of the mouth. The actions following 
 from stimulation of 14 and 15 are identical in the two animals, 
 the first being pricking of the opposite ear, the second twist- 
 ing of the opposite nostril, as if on application of a pungent 
 odour. 
 
 The contrast between the two brains, as illustrated by 
 electrical stimulation, is seen first in the absence of certain 
 numbers from the figure of the dog's brain. The absent marks 
 
102 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 are 2, 6, and (a, b, c, d). I do not include No. 10, as it has been 
 accounted for as included within 9. There are thus three 
 distinct centres wanting. Indicated by their respective move- 
 ments, these three represent : First, " Complex movements of 
 the thigh, leg, and foot, with adapted movements of the trunk, 
 by which the foot is brought to the middle line of the body, as 
 when the animal grasps anything with its foot, or scratches its 
 chest or abdomen ,; (No. 2) : Second, elevation and bending 
 backwards of the fore-arm, "by which the hand is raised 
 towards the mouth " (No. 6) : Third, " individual and com- 
 bined movements of the fingers and wrist, ending in clenching 
 of the fist," marked a, b, c, d. Interpreting these negative 
 results, we have confirmation of the accuracy of the method 
 employed. The dog does not grasp an object with his hind 
 foot. He does, indeed, raise his foot to the middle line of the 
 body to scratch the part, but this is little more than the repe- 
 tition of the movement involved in advance of the hind foot, 
 which is accounted for by the centre numbered 1. The dog 
 does not bend back bis forepaw, so as to bring anything to his 
 mouth; and he knows nothing of the movement of fingers 
 requisite for clenching the fist. These negative results afford 
 additional illustration of the position, that the structure of the 
 nerve centre is harmonised with the structure of the body. 
 Where nerves, muscles, and joints are, there is, in correlation 
 with them, a centre to provide for their movement by direction 
 of nerve energy on the mechanical arrangements. 
 
 The contrast between the two brains is seen, secondly, in the 
 presence of certain features in the brain of the dog which are 
 not found in the monkey. These are not indicated by the 
 introduction of any new numbers upon the figure representing 
 the dog's brain, and on this account it is of more consequence 
 to refer to them. As the centres marked are all connected 
 with movements of certain members of the body, and as all the 
 members brought into motion belong to both monkey and 
 dog, there could be no example of absence of one of the centres 
 in either brain, such as would be in the absence of No. 3 (pro- 
 viding for movement of the tail), if the human brain could be 
 mapped out in like manner. As, therefore, there cannot be 
 the addition of a number to mark any peculiarity in forms of 
 
iv.] LOCALISATION OF FUNCTIONS. 103 
 
 action, we need to guard against risk of overlooking suck 
 peculiarities. One of tkese peculiarities brougkt out in the 
 description already given is tke combination of movements of 
 the mouth, muscles of the side, face, and eyes, showing that an 
 association of several centres may be established in any brain 
 because of the peculiar form of action assigned to certain parts 
 of the body. Another peculiarity is connected with No. 9. 
 Stimulation of this leads to common results in both cases, viz., 
 opening of the mouth and movement of the tongue. But in 
 the case of the dog, when this centre was excited by the electric 
 current, the animal was heard to bark. This deserves notice, 
 along with the fact that the result was only occasionally 
 obtained at first, and then the sounds seemed to be somewhat 
 suppressed. Dr. Terrier's words are: "Occasionally, as de- 
 scribed in my first experiments, the stimulation of this region 
 caused also vocalisation, or feeble attempts at barking or 
 growling. In a subsequent experiment this was exhibited in 
 a very striking manner. Each time the electrodes were 
 applied to this region, the animal uttered a loud and distinct 
 bark. To exclude the possibility of mere coincidence, I then 
 stimulated in succession various parts of the exposed hemi- 
 sphere, producing the characteristic reaction of each centre, but 
 no barking. The reapplication of the electrodes to the mouth 
 centre elicited the barking, and did so invariably several times 
 in succession." 1 Barking is an essential feature in the life of 
 the animal, and if the centre which provides for opening of 
 the mouth can also when stimulated induce the animal to bark, 
 this points towards an established relation or co-ordination of 
 centres in the brain more widely than the experiments other- 
 wise represent. There is external inducement to bark, and this 
 implies that a centre of sensibility must be co-ordinated with 
 the motor centre, just as we find that the centre, No. 15, which 
 induces movement of the nostrils, lies contiguous to the olfac- 
 tory tract. 
 
 Such experiments as those now described are exposed to 
 serious difficulties in execution. Grave injury is done in expos- 
 ing the brain to view, occasioning loss and diffusion of blood, 
 and disturbance to the whole body. This disturbance is, how- 
 
 1 West Siding Reports, vol. iii. p. 150. 
 
104 THE RELA TIONS OF MIND AND BRAIN. [chap. 
 
 ever, greatly modified by the torpor which is induced under the 
 influence of chloroform or other anaesthetic, but this involves 
 an abnormal condition of the body, thereby introducing a new 
 difficulty. When the brain is exposed and the electrodes 
 applied, there is great probability in favour of diffusion of 
 electric influence by means of the delicate membrane which 
 covers the organ and carries the blood supply to all its parts. 
 Great as these difficulties are, however, and sufficient to account 
 for considerable diversity of result in the earlier stages of 
 investigation, the uniformity and regularity of effect produced 
 in a multitude of cases under many hands, warrant the con- 
 clusion that electric stimulation has produced effects analogous 
 to ordinary functional activity. The experiments of Hitzig 
 and Ferrier have been keenly criticised, not from one stand- 
 point only, but from many, each critic working under influence 
 of the hypothesis most attractive to his own mind. Dr. 
 Dodds has given a valuable summary of the results of these 
 criticisms and experiments, looking at the subject from a phy- 
 siological, a pathological, and anatomical point of view. 1 The 
 investigations of the New, York Committee, of Dr. Burdon- 
 Sanderson, Brown-S^quard, Carville and Duret, Goltz, and 
 others, have been directed to the subject, and whatever differ- 
 ences of opinion otherwise exist, it is granted that the move- 
 ments described by Ferrier do take place, and that they result 
 from stimulation of the centres as marked. Carville and Duret 
 have given ample confirmatory testimony. 2 The New York 
 Committee of the Society of Neurology and Electrology have 
 shown by experiments repeated at intervals on the same spot 
 from ten to forty times, that the results were easily obtained 
 by application of the electrodes to the centres marked, but that 
 deviation by a very slight degree was sufficient to prevent the 
 result being attained. 3 
 
 Alongside the test afforded by repeated experiment, there has 
 been the further test of destruction of the centre, with observa- 
 
 1 Journal of Anat. and Physiol, vol. xii. Three articles, pp. 340, 454, 636. 
 
 2 The references, as giveD by Dr. Dodds, are, Gazette Midicale de Paris, Jan. 
 10, 1874 ; and Archives de Physiologie, 1875, vol. ii. See also Examen de 
 quelques points de la Physiologie du cerveau, 1873. 
 
 3 New York Medical Journal, March 1875, p. 225. 
 
iv. LOCALISATION OF FUNCTIONS. 105 
 
 tions of the consequences in the experience of the animal 
 when recovered from the torpor. Dr. Burdon- Sanderson with 
 a thin knife cut into the grey matter, so as to sever the con- 
 nection between the superficial area and the part beneath. The 
 part so severed from its organic relation was allowed to remain 
 in position. Under these altered conditions the experiment of 
 electric excitation was repeated, and the same results were 
 produced as before. The incision was next carried deeper, 
 while the severed part was allowed to remain in position. This 
 disturbed the relation with the muscles, and prevented action 
 following. The severed part was then removed from its posi- 
 tion, and the electrodes applied to the inner portion of the 
 organ thus exposed. Again the results were obtained as at the 
 first. The process was continued until the band uniting the two 
 hemispheres (corpus callosum) was reached, and the active re- 
 sults were again obtained. The incision was at length carried 
 down as far as the motor ganglion at the base of the brain 
 (corpus striatum), and there the muscular movements were 
 obtained as at the first, and even with greater distinctness. 1 
 These results were confirmed by the investigations of Braun 2 
 and of Putnam, 3 and of Hermann, 4 who adopted a variety of 
 methods. 
 
 The question now arises, What significance is to be assigned 
 to the results of incision ? If the movements can be obtained 
 after the removal of the grey matter of the brain, what is the 
 inference as to the functions of the grey matter ? The first 
 suggestion may be that these later results are unfavourable to 
 the conclusion that distinct functions are localised in fixed 
 areas of the brain. It may be said that Ferrier's experiments 
 show nothing more than this, that there is in the grey matter 
 the power of conducting electric influence to the nerve masses 
 
 1 Proceedings of Royal Society of London, 1873. 
 
 2 Eckhard's Beitrage zur Anat. wild Physiol., Band vii. 
 
 3 Boston Medical and Surgical Journal, vol. xci. 
 
 4 Pfluger's Archiv., Band x. 
 
 I am indebted for these references to Dr. George T. Beatson of this 
 University, who, with the aid of Mr. Stirling, of the Anatomical Museum, 
 assistant to Professor Turner, has given special attention to this subject. 
 The very important anatomical bearings of this whole line of investigation are 
 fully treated by Dr. Dodds — Journal of Anat. and Physiol, vol. xii. p. 454. 
 
io6 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 at the base of the brain, and through these to the nerve lines 
 connected with certain muscles. This is the view taken by- 
 Hermann. But this view gives no explanation of the possi- 
 bility of stimulating the grey matter. It is granted that con- 
 ductivity is characteristic of nerve fibre, and when you have 
 reached such fibres the conducting lines are before you. If 
 electric stimulus be carried along such lines, this is in har- 
 mony with the admitted functions of the nerve fibres, and it 
 is a fact which suggests that there is some analogy between 
 nerve energy and electricity. This admitted, there is nothing 
 new suggested in showing that the nerve fibres have power of 
 conductivity. But it is something new and unsupported by 
 evidence to suggest that the grey matter is merely an extension 
 of the conducting lines, in effect continuing these lines to the 
 region of the skull. In view of the structure of the grey 
 matter, it seems impossible to maintain this position. 1 And if 
 so, the results of electric stimulation of the grey matter are 
 unchallenged, while one division of the results — that concerned 
 with conductivity of certain nerve lines to distinct muscles — 
 is confirmed by a second line of experiment. Everything is 
 granted which at this stage the theory of localisation requires. 
 It is admitted that, under the areas marked, the nerve lines 
 are found which are connected with the parts of the body 
 specified. If, then, these nerves are operated upon by applica- 
 tion of the electrodes to the grey matter lying directly above the 
 fibres, it follows, either that electricity is so far analogous to 
 nerve energy, that, when the grey matter is thrown into a state 
 of torpor (as in chloroform narcosis), electricity can act through 
 the grey matter upon the nerves ; or, electricity is so assimi- 
 lated to nerve energy, that it acts upon the nerve cells, causing 
 them to discharge their nerve energy down those lines con- 
 nected with the cells brought under influence. In either case 
 the theory of localisation is upheld. The action of nerve and 
 muscle is effected through the agency of the grey matter; 
 but whether by the isolated action of the area of grey matter 
 operated upon, or by the united action of the whole cortex con- 
 centrated upon that area, is not determined. 
 
 1 See Dr. Dodds on Localisation, Journal of Anat. and Physiol, vol. xii. 
 p. 458. 
 
iv.] LOCALISATION OF FUNCTIONS. 107 
 
 The question is now clearly before us, What is the legitimate 
 interpretation of the facts connected with electric stimulation 
 of the grey matter ? These facts are such as to suggest some 
 distinctions among the resultant actions. In all cases the 
 stimulating influence has to do with movement of the muscles. 
 But in some cases the relation of the action to what is external 
 to the animal is different from that which appears in other 
 cases. The movements of the limbs, as in running, or as in 
 lifting the hand to the mouth, are different in this respect from 
 the twisting or twitching of the lip and nostril analogous to 
 that witnessed when a pungent odour is applied to the nose. 
 The first class of actions arises more obviously by stimulus from 
 within ; the action last named is- in appearance a successful 
 imitation of an action which is the result of external stimulus. 
 In the one case the experimenter seems to stand at the source 
 of activity ; in the other case, at the turning-point or junction 
 at which an impression from without turns round upon the 
 motor line. This distinction may prove to be one in appear- 
 ance merely, and not in reality, because an influence from 
 without may operate in the first case, as well as in the last, the 
 difference being merely that the external influence is detected 
 in the one case, and not in the other. The difference does, 
 however, appear, and it brings up the distinction between 
 sensory and motor nerves, and also the contrast between direct 
 and reflex actions, suggesting different lines of inquiry as to 
 possible forms of interpretation. This suggestion is the more 
 important in view of the negative results of electric stimulation 
 over the unmarked portions of the brain. 
 
 The position to which we are brought is this : — The centres 
 marked and numbered on the surface of the brain may be 
 either purely motor ; or sensori-motor, that is, centres which 
 receive sensory impressions, and thereby stimulate movement ; 
 or they may be in part the one, and in part the other. Dr. 
 Ferrier has put the point thus : — " The mere fact of motion fol- 
 lowing stimulation of a given area does not necessarily signify 
 a motor region. The movements may be the result of some con- 
 scious modification incapable of being expressed in physiological 
 terms, or they may be reflex, or they may be truly motor in the 
 sense of being caused by excitation of a region in direct connec- 
 
108 THE RELA TIONS OF MIND AND BRAIN. [chap. 
 
 tion with the motor parts of the crus cerebri." 1 I am not at pre- 
 sent considering the possibility of the first of the three alterna- 
 tives ; but altogether reserve that for a later and distinct stage of 
 this inquiry. 3STo disadvantage can here result from this reserva- 
 tion, for even if there be " conscious modifications incapable of 
 being expressed in physiological terms," these modifications 
 must be in some sense the cause of stimulation, as the experi- 
 menter is who directs the electric current ; and in that case we 
 have no other alternatives as to classification of movements than 
 these two, purely motor, and sensori-motor. And even with 
 this twofold classification there is need for caution, for it must 
 be observed that we are merely raising the question whether 
 there may not be two classes of centres from which movements 
 are produced. We are asking whether there may not be a 
 motor centre properly so called ; that is, a centre from which 
 immediately or directly the muscular movements are produced ; 
 the other, a centre of sensibility so connected with a motor 
 centre as to be capable of stimulating the true motor centre, 
 thus being primarily a centre of sensibility, but at the same 
 time mediately and indirectly a centre of activity. This state- 
 ment of the alternative is sufficient to show that there is and 
 can be but one class of motor centres, embracing exclusively 
 those centres which are directly or immediately in communica- 
 tion with motor nerves. The whole question now before us, 
 therefore, is, whether there may not be centres of sensibility so 
 closely connected with motor centres, that, when stimulated, 
 they inevitably stimulate the motor centre with which they 
 are connected. And this question is raised with the view of 
 guarding us against a too hasty acceptance of the conclusion 
 that the numbered centres are all motor centres properly so 
 called. Yet must it be true that at each numbered circle we 
 are in any case either upon a motor area, or so near it as to be 
 in contact with it. In all the examples given there are motor 
 centres reached by electric excitation; whether these motor 
 centres are localised on the superficial area marked, is the point 
 to be determined. 
 
 As previously indicated, a twofold classification of the centres 
 is suggested by the results obtained. The distinction is clear 
 1 Functions, i>. 163. 
 
IV.] LOCALISA TION OF FUNCTIONS. 
 
 109 
 
 iu the contrast between No. 1 and No. 15, — the first and last 
 of the centres marked on the brain of the monkey, — the 
 movement of the limb, and the movement of the nostril. In 
 the last case we discover by actual observation, how the move- 
 ment is induced. The stimulating influence is an external 
 agent applied to the organ of smell. In the first case we do 
 not know how the movement is produced in ordinary life, that 
 is, we do not find that any external agent produces this move- 
 ment as in the former case. Our ignorance here marks a point 
 from which further inquiry needs to be started. The recogni- 
 tion of this has led to an additional course of investigation. After 
 the centres had been mapped out, and the results of stimulation 
 recorded, destruction of the centres was resorted to, and the 
 consequent injury to animal life was noted, the results being 
 further tested by examination of the brain after death. By this 
 method a distinction was drawn between Sensory Centres and 
 Motor Centres, thereby advancing a stage further the inquiry 
 as to the functions of different parts of the brain. In the 
 manner thus described, Dr. Terrier, taking the brain of the 
 monkey as the test, reached the following conclusions, — that 
 the centres marked 13 and 13' (angular gyrus) indicate the 
 centre of vision ; those below (in temp, sphen.) marked 14 
 are the centre of hearing; that the centre still lower (on 
 the lower border of the same lobe) marked 15, is the centre 
 of smell and taste ; and that the centre of touch is found 
 in an internal region (hippocampus major), and cannot be 
 marked on the surface. By the same method it was inferred 
 that the other centres were motor centres, inasmuch as their 
 destruction was followed by paralysis of the part previously 
 shown to be in relation with it, and in some instances com- 
 plete epilepsy ensued. 1 There is little need to go into details 
 as to a whole series of cases, but a single example may be 
 selected from each side in this twofold classification. I take 
 as illustration of the centre of sensibility, those areas marked 
 13 and 13', stimulation of which was attended by " movements 
 of the eyeballs, frequently associated with movements of the 
 head to the opposite side, and very often contraction of the 
 
 1 See Dr. Dodds on Localisation, Journ. of Anat. and Physiol., vol. xii. 
 p. 458. 
 
no THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 pupils." 1 Destruction of the region indicated (angular gyrus) 
 caused " blindness in the opposite eye." But here appears one 
 of the features in such cases which calls for special considera- 
 tion, as hearing on the relations of the hemispheres. The 
 destruction of this part of the brain, hypothetically the centre 
 of vision, is effected only on one side, that is, the left hemi- 
 sphere ; and in consequence the right eye becomes blind. But 
 the loss of sight in that eye is not permanent if the analogous 
 portion of the brain on the right hemisphere remains uninjured, 
 " compensation rapidly taking place, so that vision is again 
 possible with either as before." 2 In order to test the result, the 
 left eye, as the one likely to be unaffected, was bandaged ; the 
 right eye was exposed. The animal " did not flinch when held 
 close to the gas-light ;" and did not recognise its companions 
 in the cage. About an hour afterwards the animal was taken 
 out of the cage again, the bandage removed from the left eye, 
 and the animal set down on the floor. " It immediately looked 
 round, and ran nimbly to the cage, and joined its companions." 3 
 " Next day, however, on the left eye being again bandaged, the 
 animal gave evidence of sight by running up to its cage, the 
 door of which was shut, and lapping water from a dish, which 
 it reached by inserting its hand between the bars."* A single 
 day seems to have been sufficient, if, indeed, this may be re- 
 garded as the method of recovery, to establish a relation between 
 the right eye and the right hemisphere such as to secure anew 
 the efficiency of the injured eye. In another case the same 
 portions were destroyed on both hemispheres, and the result was 
 total blindness of both eyes. In such a case, Dr. Ferrier says, — 
 " The loss of vision is complete and permanent, so long, at least, as 
 it is possible to maintain the animal under observation." But 
 there is one fact to be specially noted in the example adduced 
 for illustration. "The pupils contracted to light, and light 
 flashed in the eyes caused the animal to wince." Nevertheless 
 the evidence of total blindness was complete. A piece of apple 
 dropped so as to come into contact with the hand was picked 
 up and eaten. A cup of tea was placed to the animal's lips, 
 when it at once began to drink ; but when taken from its lips 
 " the animal was unable to find the cup, though its eyes were 
 1 Ferrier's Functions, p. 164. 2 lb. 3 lb. p. 1G5. 4 lb. 
 
iv.] LOCALISATION OF FUNCTIONS. m 
 
 looking straight towards it." After this test had been repeated 
 several times, the cup was again placed to its lips, when " it 
 plunged in its head, and continued to drink though the cup 
 was gradually lowered, and drawn half-way across the room." 
 On this evidence the conclusion seems warranted that the 
 centres marked 13 and 13' (angular gyrus) indicate the centre 
 of vision. By similar evidence the centres marked 14 (Superior 
 Temporo-Sphenoidal convol.) indicate the centre of hearing; 
 and the centre marked 1 5 (lower and inner part of the Temp- 
 Sphen.) indicates the centre of taste and smell, these two being 
 so closely related that it was found impossible rigidly to dis- 
 tinguish them. 1 If now we combine the two lines of evidence 
 adduced, — the one from electric stimulation, the other from 
 destruction of the centre identified by the former process, — 
 we have a double result. In one sense these centres are motor, 
 that is, these centres are so related to the cells which act upon 
 certain motor nerves, that application of electric excitation 
 induces movement. In another sense they are sensory centres, 
 for destruction of the part is followed by the loss of one or 
 other of the special senses. These two conclusions are estab- 
 lished on evidence equally explicit, and both must be kept 
 clearly before us, so that the one be not obscured by regard to 
 the other. There is nothing in the whole course of the observa- 
 tions to throw doubt upon the duality of function at these 
 three centres. 
 
 In view of the completeness of result which follows destruc- 
 tion of the defined part in both hemispheres, it may be granted 
 that these centres are primarily sensory ; but even this position 
 needs to be taken guardedly, and to the extent only of admit- 
 ting that the actions consequent on electric stimulation are in 
 a sense reflex. If next we inquire as to the motor centre for 
 those actions, the utmost that can be said is that the centres 
 of sensation must have their cells connected by distinct fibres 
 with cells which are functionally related to the motor nerves 
 brought into play. There is nothing in the evidence to lead to 
 the supposition that the motor centres are removed from the 
 circles described, but a great deal to warrant the conclusion 
 that they are included within these circles. More particularly, 
 1 Ferrier's Functions, p. 184. 
 
112 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 taking the visual centre as the illustration, it is to be remarked 
 that, notwithstanding the complete loss of vision by destruction 
 of the centre in both hemispheres, there was still sensibility to 
 the action of light, and consequent exercise of the motor nerves. 
 " The pupils contracted to light, and light flashed in the eyes 
 caused the animal to wince." 1 Though these eyes were blind, 
 there was still sensitiveness in them ; and, consequent on this 
 sensitiveness, reflex action in wincing. We know, indeed, that 
 a nerve retains its sensibility after its connection with the 
 nerve centre has been severed, and even for a considerable time 
 after death has ensued. "We are, therefore, not entitled to con- 
 clude that such sensibility as that shown after blindness 
 implies a relation of sensory nerves with some other centre 
 than that destroyed. And so, as to the consequent movements, 
 it does not seem perfectly safe to infer that they imply connec- 
 tion with a motor centre somewhere beyond the destroyed area, 
 though it is possible that this may be involved. Further, the 
 results which follow excision of the part, and subsequent 
 electric stimulation of the portion beneath the part removed, 
 as in the experiments of Burdon-Sanderson and others, indicate 
 that the motor nerves are in direct contact with the centre 
 operated upon, and thus they favour the supposition that 
 within the defined circle we have in reality a motor centre, as 
 well as a sensitive. As Dr. Dodds has stated it, '' In these 
 cases there is as much reason to believe that the so-called 
 sensory cortex is in part motor, as that the motor region is 
 motor." 2 Dr. Dodds has ably illustrated and supported the 
 position that a sensory centre also contains motor cells, and 
 that a motor centre also contains sensory cells. This is the 
 view which seems most naturally to account for all the facts 
 recorded in connection with the several experiments. For 
 reflex action these things seem needful, — a centripetal or in- 
 carrying nerve, a sensory cell to which the impression may be 
 carried, a connecting fibre placing the sensory cell in connection 
 with the motor cell, and a centrifugal or out-carrying nerve. 
 This is the least amount of mechanism which can provide for 
 the results known. And though there is not direct evidence of 
 
 1 "Ferrier's Functions, p. 1G5. 
 
 2 Localisation of Functions, Jour, of Anat. and Physiol., vol. xii. p. 356. 
 
iv.] LOCALISATION OF FUNCTIONS. 113 
 
 the fact, the results of electric stimulation seem to favour the 
 conclusion that the sensory cell and the motor must be in con- 
 tiguity. If we must in each case suppose not merely a single 
 cell, but a group of cells, the argument for local contiguity will 
 still remain of the same force. 
 
 I proceed now to a single illustration of the bearing of the 
 phenomena of destruction on the centres which are regarded 
 as primarily motor centres. The distinguishing feature of 
 those centres, numbered from 1 to 12, is the apparently pur- 
 posive nature of the action, resulting from stimulation. The 
 action is obviously adapted to the accomplishment of a parti- 
 cular end. Thus the throwing forward of the limbs, the 
 movement involved in grasping an object, the turning of the 
 head round as if better to observe some object, are actions 
 which are done to accomplish a definite end. And such move- 
 ments as these result from stimulation of the centres which lie 
 to the front of those already considered. We may further say, 
 that such movements more nearly resemble the class of actions 
 which in our own experience we commonly denominate " volun- 
 tary actions." "We are, however, still restrained from use of 
 the term " voluntary " or " volitional," as we are not yet in 
 possession of materials by which to indicate its proper mean- 
 ing. It is, therefore, needful meanwhile to withhold this term, 
 as there are at this stage no data with which to decide what 
 actions are voluntary actions ; nor can we have such data until 
 we come to study the facts of personal experience. All use of 
 the term " voluntary " as if it were applicable within the area 
 of physiological observation, is provisional and hypothetical, 
 incapable of definition without passing over into another area, in 
 order to bring thence the needful materials ; and, when this has 
 been done, we are without evidence of its applicability within the 
 sphere under observation. It may, indeed, be said that there 
 are two distinct features of the class of actions now under 
 review, both of which have been brought out by electric stimula- 
 tion, the one negative, the other positive. The one is that we 
 do not find it possible to produce the action by application of 
 some stimulating influence to a sensitive part on the surface of 
 the body, such as the nostril, eye, or foot. The other is that 
 the action is directed towards a definite result. The absence 
 
 H 
 
U4 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 of power on our part needs, however, to be regarded with caution 
 as evidence of something distinctive, for there is nothing in 
 which we are more apt to be misled than in positive inference 
 from negative evidence. The one really definite and trust- 
 worthy distinction of the class of actions now under considera- 
 tion is their manifest adaptation to secure a single end, 
 peculiar to the moment when the action takes place. The end 
 may be the sight of some object, movement towards an object, 
 or grasping an object; but there is some distinct end served 
 by the movement at the moment, and, besides, the relation of 
 movement and end may be matter of observation. It is to be 
 remarked, however, that in indicating some definite and obvi- 
 ous end as characteristic of these actions, it is neither implied, 
 on the one hand, that reflex actions, such as sneezing or twitch- 
 ing the nostril, have not an end to serve ; nor, on the other, 
 that the action, whose immediate end is obvious to us, is done 
 by deliberate purpose on the part of the animal, as when a man 
 walks across the room for a book, or takes up a pen to write a 
 letter. 
 
 For illustration of this class of movements, I take the third 
 case given by Dr. Ferrier, as it is restricted to a single centre, 
 and therefore more definite. First, by electric stimulation, 
 No. 6 on the left hemisphere of a monkey was identified as 
 that from which elevation and bending of the right arm was 
 effected. After the centre of grey matter had been destroyed, 
 there was paralysis of the right arm. When this arm was 
 extended, the animal had no power to bend it ; and when the 
 animal was lifted, the arm hung loosely by its side, while the 
 other limbs continued under control in the usual manner. This 
 result, applicable to a single centre, presents an > example of 
 what was found to hold true when the destruction of the grey 
 matter was resorted to on a wider area. In the case of the dog 
 and cat, complete paralysis does not follow destruction of the 
 centre, but the injury to movement is in accordance with the 
 facts which appear in the case of the monkey. There is thus 
 confirmation of the results attained under electric stimulation, 
 that the centres situated in advance of those previously con- 
 sidered (Nos. 13, 14, and 15), namely, those numbered from 
 1 to 12, are primarily motor centres. The question which 
 
IV.] LOCALISATION OF FUNCTIONS. 115 
 
 remains undecided is, whether those centres, which are pri- 
 marily motor centres, may not also be in another phase sensory 
 centres. The special point of interest here is, what answer 
 could be given to the question, Is there any possibility of 
 stimulating these motor centres by acting upon any portion of 
 the surface of the body? Could it be shown, for example, 
 that the muscular sense can exert any stimulating influence 
 over the mechanism of animal locomotion ? There is consider- 
 able evidence in human experience to suggest such a connec- 
 tion. But we are without direct evidence of this in the facts 
 obtained under electric stimulation, and subsequent destruction 
 of portions of the grey matter. 
 
 In absence "of direct evidence in any way, and consequent 
 inability to verify reflex activity as characteristic of the move- 
 ments, it has been suggested that the motor centres may be 
 taken as centres of voluntary motion. But this suggestion 
 labours under the same disadvantage as the other, in so far as 
 the absence of distinct evidence is concerned. Such experi- 
 ment as that adopted for ascertaining localisation of function 
 in the brain could not possibly afford testimony on such a 
 question. An animal rendered insensible by chloroform, — 
 abnormally torpid, — could not exercise voluntary control, even 
 if such control Were possible to it in its normal condition. On 
 the other hand, when the animal is in its normal condition, we 
 can have no evidence of the action of will. For evidence of 
 the action of a power of will we are dependent altogether upon 
 the facts of personal experience. Something more than mere 
 simple reflex action seems to be involved in the actions of the 
 monkey, dog, and cat, which are observed when the animals are 
 under the influence of chloroform, and when the motor centres 
 are stimulated. But whether this is a more complex and indi- 
 rect process of reflex activity, or a case of voluntary action, 
 there is no evidence at command by which to decide. Dr. Dodds 
 suggests that " the only probable explanation appears to us to 
 be that the cells of this motor region of Ferrier form, as it 
 were, the motor alphabet of the will. In a way as yet not 
 understood, the will is able to decide upon certain movements, 
 and then, compositor-like, to pick out the areas by whose 
 stimulation the desired result is accomplished. This is rather 
 
n6 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 a loose way of expressing one's-self, but the present uncer- 
 tainty as to the physiological equivalent of will and its mode 
 of action must be our excuse." 1 That this may be a probable 
 explanation I am prepared to allow; that it is the only possible 
 or probable explanation can hardly be maintained in view of 
 what is known as to reflex actions. When we come to analyse 
 human experience, it will be possible to speak more definitely 
 of Will and its part in the determination of muscular move- 
 ments. When we advance to that fuller knowledge which 
 personal experience gives, including the deliberations and 
 decisions'which precede physical exertion, we may more readily 
 grant that such centres as those now under consideration may 
 constitute a kind of mechanical alphabet capable somehow of 
 being employed by intelligence and will. But when the facts 
 of human experience are referred to, or even by implication 
 used as aids to fill up what is lacking in physiological observa- 
 tion, we must also remember how vastly these facts widen 
 our knowledge of the range of reflex action. I refer specially 
 here to the well-known circumstance that actions which at 
 first are performed with difficulty, requiring constant attention 
 and self-directed effort for their performance, become so simple 
 that they are done without any conscious effort. They do in 
 fact become in a large measure reflex. In view of this fact, 
 there appears to be need for great caution before we assent to 
 a general statement of the possible range of reflex action. 
 Besides, if we take into account the need for recognising a 
 doctrine of "unconscious cerebration," as developed by Lay- 
 cock and Carpenter, 2 and now generally recognised, though 
 with addition of co-operation of conscious activity, 8 additional 
 reason is afforded for caution in our conclusions as to the 
 action of the motor centres in animal life. More expressly, it 
 must be kept in view, when it is said that " the will is able to 
 decide upon certain movements," that the language is that of 
 
 1 Localisation of Functions, etc., Journal of Anatomy and Physiology, vol. 
 xii. p. 357. 
 
 2 Layoook's Mind and Body, vol. ii. p. 465 ; Carpenter's Human Phy- 
 s'wlogy,x>. 647, 7th ed. ; Carpenter's Mental Physiology, p. 515. 
 
 8 Vide Dr. Ireland's paper, "Can Unconscious Cerebration bo proved ?"— 
 Journal of Mental Science, October 1875. 
 
iv.] LOCALISATION OF FUNCTIONS. 117 
 
 human experience, and that we are without evidence of its 
 being applicable beyond this area. 
 
 In estimating the results of electric stimulation of the grey 
 matter of the brain, I have now briefly to consider the facts 
 bearing upon those portions which remain unmarked. These 
 are the " silent portions " of the brain, or portions which under 
 stimulation yield "negative results." Described generally, 
 they are the anterior portion of the frontal lobe, the back 
 portion of the brain, or occipital lobe, and the concealed central 
 lobe, or Island of Eeil. Eepeated application of the electrodes 
 to these parts has altogether failed to call forth any response. 
 This absence of result is remarked in the case of all animals 
 subjected to test ; and the portions of the brain which remain 
 silent are analogous. Over the central portion of the organ, 
 both in its upper and under division, response is promptly 
 given, but the front region and the back give no sign. This 
 fact introduces a serious perplexity, on which as yet but little 
 light is thrown by those who have devoted themselves to this 
 line of research. On the other hand, uniformity of result in 
 so many cases is suggestive of some general conclusion as to 
 brain function. 
 
 In the circumstances, our first resort must be to anatomical 
 science, in so far as it may indicate the direction of nerves, 
 as connected with the several portions of the brain. 1 Our 
 attention is thus turned on the nerve tract (cerebral peduncles), 
 which pass up towards the nerve masses or ganglia (corpus 
 striatum and optic thalamus), lying at the base of the brain 
 proper ; and from these to the distribution of the nerve fibres 
 to the grey matter, constituting by their radiation the gathering 
 known as the crown (corona radiata). On this line of inquiry 
 we are favoured by the consideration that the two large basal 
 masses or ganglia are generally admitted to be distinguishable 
 by the class of nerves which is most prominent in each. 2 The 
 one (corpus striatum) occupying the front and outermost situa- 
 tion, twofold in form after the analogy of structure appearing 
 everywhere in the nerve centre, is made up largely of motor 
 
 1 I am here under special obligatiou to the Third Article of Dr. Dodds — 
 Journal of Anatomy and Physiology, vol. xii. p. 636. 
 
 2 See fig. 11; p. 32. 
 
u8 THE RELATIONS OF MIND AND BRAIN. [CHAP. 
 
 nerves, with some small admixture of sensory. The other 
 (optic thalamus) lying behind and within the former, and also 
 twofold in shape, is composed mainly of sensory nerves, with 
 some small share of motor. Looking next at the two large 
 bands of fibre which are seen above the bridge, we find one 
 bending towards the left, the other towards the right (crura 
 cerebri). The superficial portion (crusta) of these two bands 
 passes for the most part into that ganglion which is regarded 
 as chiefly motor (corpus striatum) ; the deeper portion (tegmen- 
 tum) into that ganglion recognised as chiefly sensory (pptw 
 thalamus)} Thus far our course of inquiry is cleared by 
 having a general distinction between motor and sensory nerves, 
 the one class on the surface, the other within ; the one concen- 
 trated in the frontal mass above, the other on the mass which 
 lies in the interior. Our interest next turns upon what is said 
 as to the fibres which make up these tracts and masses. Here 
 there is a considerable degree of complexity. If, however, our 
 attention be directed mainly on the parts of the brain about 
 which we are now inquiring, viz., the front, back, and inner lobes, 
 we shall find a clew more easily followed. The way is further 
 cleared by noticing that several of the fibres of both the outer 
 and the inner portion (crusta and tegmentum) of the nerve 
 tracts terminate in the masses at the base of the brain. "With 
 these, therefore, we are not here concerned. Other fibres of 
 both portions pass directly through to the grey matter. And 
 while fibres terminate in the masses at the base of the brain, 
 new fibres start from these masses. I shall take first the 
 course of the outer or motor portion (crusta) of the tracts. 
 Some of the fibres of this division pass directly up to the grey 
 matter of the back lobe (occipital), and to the under-middle. 
 Of those which originate from the basal mass (corpus striatum), 
 by far the largest number go towards the grey matter of the 
 frontal lobe, and some few to the concealed central lobe or 
 island. Here then we have motor nerves traced to all the three 
 silent parts of the grey matter, but the larger number are 
 directed towards the front. Tracing now the course of the 
 deeper or sensory portion (tegmentum) of the tracts, the fibres 
 
 1 Quain's Anatomy, vol. ii. p. 538 ; Turner's Anatomy, vol. i. p. 290 ; 
 Ferrier's Functions, p. 236. 
 
IV.] LOCALISATION OF FUNCTIONS. 119 
 
 of this pass up to the inner mass (optic thalamus) at the base 
 of the brain, where they largely terminate. But from the grey 
 matter of this basal mass arise a great many radiating fibres 
 which pass up to the grey matter of the brain in all its lobes. 
 Those from the posterior go to the lack lobe (occipital), and to 
 the under-middle, and in this way become associated with the 
 nerves of special sense, sight, and smell, which take this course; 
 those from the anterior go to both the under and upper middle 
 lobes, and to the frontal lobe and the island. Thus again we 
 have sensory nerves traced to all the three silent portions of 
 the grey matter. I shall only briefly state the conclusions 
 which seem warranted by these data. First, motor and sensory 
 nerves go together to all divisions of the brain ; to those which 
 are silent under electric stimulation, as well as to those which 
 respond. On anatomical grounds, it seems warrantable to 
 maintain that all the five lobes must be sensori-motor ; and, if 
 the theory of definite centres in the grey matter, with special 
 functions, be accepted, both sensory centres and motor centres 
 must be found in all the lobes. Second, There is a preponder- 
 ance of sensory nerves to the back region of the brain (occipital 
 lobe), and a preponderance of motor nerves to the frontal 
 region. These are the two conclusions which may be regarded 
 as fairly well ascertained since the investigations of Meynert 
 were specially directed upon the distribution of the nerve fibres 
 to the grey matter of the brain. 
 
 These two conclusions seem to me to throw no doubt over 
 the positive results attained by electric stimulation. The his- 
 tory of these results, it will be remembered, was this ; first, a 
 series of movements was obtained from all the centres marked, 
 apparently suggesting that they were all alike motor ; next, a 
 distinction was drawn, on the ground of the recognised effects 
 of external stimulus in some cases, thereby making some of 
 the centres primarily sensory in their character, but leaving 
 undisturbed the earlier view that they were at the same time 
 motor centres, subordinated to the sensory ; and lastly, the 
 remainder were left in their original position as primarily motor 
 centres, but with the acknowledgment that nothing can be done, 
 so far as yet appears, to determine whether these may not be 
 subordinately sensory, as the others are subordinately motor; 
 
120 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 Anatomical research clearly favours the view that sensory 
 and motor nerves are distributed together to all the lobes, 
 and to all the convolutions in each. The positive results of 
 electric stimulation must, as I think, be interpreted in this 
 view. 
 
 The bearing of the two conclusions just reached, on the 
 " negative results " of attempted stimulation of the frontal and 
 back lobes of the brain, leading to the admission of "silent 
 regions," occasions more perplexity. If it be allowed that 
 electricity acts upon the nerve cells, so as to cause liberation 
 of nerve energy, and consequent nerve action, it would appear 
 to follow that it should do so in all cases. If, by use of this 
 power of stimulation, it has proved possible to distinguish 
 between sensory and motor centres, it would seem to follow 
 that the difference between the two classes of centres should 
 introduce no new difficulty. And, if there be sensory and 
 motor nerves in all parts, it would appear to follow that there 
 should be response from all when placed under stimulation, 
 and not merely from some. These considerations, when taken 
 together, must be allowed to occasion very serious perplexity. 
 
 At the same time it must be remembered that it was by an 
 -indirect process that sensory centres were distinguished. These 
 centres when stimulated responded by movements, just as in 
 the case of the other centres. If then it may be taken as a 
 fact that the single result of electric stimulation is movement, 
 there may be some abatement of perplexity. If there be forms 
 of sensibility which are experienced with little movement of 
 any part of the body, this may so far account for the fact that 
 there is no recognised movement following upon stimulation of 
 the centre in the grey matter with which it is connected. And 
 if experience of sensation be largely dependent on contact with 
 external objects, and not upon visible and separate movement 
 of the part of the body affected, additional force will attach to 
 the consideration now mentioned. Besides, if there be forms 
 of sensation which do naturally give rise to reflex action, as 
 must be held to be the case in many phases of tactile impres- 
 sion, it may be inferred that these are beyond the reach of the 
 method of experiment adopted. These considerations may be 
 regarded as applying more obviously to the back portion of the 
 
iv.] LOCALISATION OF FUNCTIONS. 121 
 
 brain (the occipital lobe), as that more prominently connected 
 with sensory tracts. But this offers little help towards account- 
 ing for absence of result in the case of the frontal portion of 
 the brain, which being, so far as anatomical testimony indi- 
 cates) prominently motor, should most readily respond. It 
 needs, however, to be remarked that the movements obtained 
 by stimulation of the centres confessedly motor are of a very 
 conspicuous order, being movements of the limbs and of 
 external organs easily kept under observation. The centres 
 marked are, moreover, in many cases centres for a large number 
 of co-ordinated movements, thus involving a larger circle as the 
 centre of stimulation, more easily detected and watched, than 
 can be looked for in other cases. It is in fact the most easily 
 observed actions whose centres have been identified. Equally 
 simple and direct identification of activity cannot be anti- 
 cipated in other cases. But more especially, we have still 
 before us the whole perplexity of self-regulation in animal 
 life, and all that may be involved in what we denominate 
 " intellectual " and " volitional " action. These are the deeper 
 perplexities of animal life which we are only being reminded 
 have not been even touched by the process of experiment. In 
 fact, the results already attained only indicate that the experi- 
 menter has broken in upon vital processes at a point some- 
 where between the originating force and the execution of the 
 action, and that he has no power to turn backwards upon the 
 originating force. The results attendant on destruction of the 
 frontal lobes give additional weight to this consideration. -Dr. 
 Terrier reports as to repetition of the test in three different 
 cases, the monkeys operated upon being " selected on account 
 of their intelligent character." In these three cases the entire 
 frontal lobes were removed. After this had been done, the 
 animals " continued to eat and drink heartily, and to exhibit 
 no signs of physical prostration." 1 Besides, "the sensory 
 faculties, sight, hearing, touch, taste, and smell, remain unim- 
 paired;" and "the powers of voluntary motion are retained." 2 
 But, " instead of, as before, being actively interested in their 
 surroundings, and curiously prying into all that came within 
 the field of their observation, they remained apathetic or dull, 
 
 1 Functions of the Brain, p. 232. 2 lb. p. 231. 
 
122 THE RELATIONS OF MIND AND BRAIN. [CHAP. 
 
 or dozed off to sleep, responding only to the sensations and 
 impressions of the moment, or varying their listlessness with 
 restless and purposeless wanderings to and fro." 1 In this 
 description the continuance of " powers of voluntary motion " 
 is apt to appear at variance with some of the other statements, 
 but the phrase may be taken in a loose sense, meaning nothing 
 more than indication of power to move without any external 
 stimulus, or without constraint. And, if this be the meaning, 
 the result in these three cases points to a want of co-ordinated 
 and concentrated activity on the part of the brain as a whole. 
 The loss of this part of the brain is not found to involve 
 paralysis of motor or sensory nerves. There are well-known 
 cases in human pathology which harmonise with this result. 
 Nevertheless it is the testimony of anatomical science that a 
 large portion of the motor nerves radiate to this portion of the 
 brain. Taking these considerations together, the limited and 
 restricted evidence at command seems to point to the general 
 inference that the governing power for the brain as a whole, 
 involving the co-ordinated and regulated use of all its func- 
 tions, comes from the frontal region, 
 
 1 Functions of the Brain, p. 232. 
 
v.] COMPARISON OF STRUCTURE AND FUNCTIONS. 123 
 
 CHAPTEE V. 
 
 COMPARISON OF THE STRUCTURE AND FUNCTIONS OF BRAIN IN 
 LOWER AND HIGHER FORMS OF ANIMAL LIFE. 
 
 While attention was being turned to the results of elec- 
 tric stimulation, some light was thrown upon the difference 
 between the brain of the dog and of the monkey. This com- 
 parison of the structure and functions of the brain in different 
 animals is so important as a guide to definite conclusions con- 
 cerning the specialities of the human brain, that I shall now 
 carry out this comparison on a more extended scale. This I 
 shall do with the aid of figures kindly granted me from Pro- 
 fessor Ferrier's Functions of the Brain, in which the numbers, 
 so far as they appear, bear the same significance as those 
 already explained in dealing with the brain of the monkey and 
 dog ; that is, they indicate " approximate physiological homo- 
 logies " in the organs. I shall still further extend the range 
 of observation by the use of figures specially prepared for 
 illustration of this department of the subject, in the prepara- 
 tion of which I have been largely indebted to the aid generously 
 afforded me by my colleague Professor Turner. 
 
 The order most suitable here is to trace the progression in 
 complexity of structure as we ascend the scale of animal 
 organism. I shall, therefore, begin with the simplest forms, 
 and from these advance to those most highly developed. 
 
 The simplest form of nerve system is that in which there is 
 only a single ganglion or central knot, into which a few fibres 
 are gathered. This is illustrated in the case of the Ascidian 
 Mollush} This animal has the primary elements of a nerve 
 system, and is accordingly sensitive to contact, and able to 
 expel anything injurious which may be drawn with the water 
 into the mouth. This mollusk is of a pear-like shape, having 
 1 Carpenter's Mental Physiology, p. 45. 
 
i2 4 THE RELATIONS OF MIND AND BRAW. [chap. 
 
 the mouth at the narrow end, and, not quite half way up the 
 body, a vent through which the water may pass after being 
 sucked in at the mouth. It consists of an outer membrane or 
 bag, within which is a muscular envelope, and again within 
 this there is at the narrow end the organ of breathing, at the 
 broader end the stomach. The Ascidian mollusks " are for the 
 most part fixed to one spot, during all save the earliest period of 
 their existence ; and they give but little external manifestation 
 of life, beyond the continual entrance and exit of the currents" 
 of water. 1 The nerve centre for this form of animal life is 
 a ganglion or nucleus situated between the mouth and the 
 vent. From this centre a few nerve fibres are sent out directly 
 to the mouth, a few more pass to the sides in closest proximity 
 to the central organ ; and a fibre is sent to the broader end, 
 over which it spreads by means of several ramifications. In 
 this example we have the simplest form of the essential 
 elements of a nerve system, with its centre, and its twofold 
 order of nerves, for there are present the two distinct forms, 
 the sensory and the motor ; and accordingly the two distinct 
 functions, sensibility by one tract, and reflex action accom- 
 plished by another tract, which meets with the first in the 
 simple central organ. 
 
 The next stage in the scale is that in which the animal has 
 a head, and within that a pair of ganglia, instead of the single 
 ganglion. This is the first appearance of the twofold formation 
 of the centre, which is thereafter continued up the whole scale. 
 This appearance is coincident with the development of two 
 sides of the body. Thereafter the centre becomes more com- 
 plex as special organs of sense, sight, hearing, and smell begin 
 to appear along with means of locomotion. The advance in the 
 scale is seen in simplest phase, in the difference between the 
 oyster and the snail, the latter being capable of shooting the 
 head beyond the shell, and in that state directing its movements, 
 which are accomplished by contraction and expansion of the 
 muscular substance. In the head of such animals as the snail 
 there is a pair of ganglia, concerning the structure of which 
 Dr. Carpenter says, " which pair, termed the cephalic ganglia, 
 is really made up of several distinct ganglionic centres, and 
 
 1 Carpenter's Mental Physiology, p. 4G. 
 
v.] COMPARISON OF STRUCTURE AND FUNCTIONS. 125 
 
 is connected by cords that pass round the oesophagus (passage 
 to the stomach) with other ganglia disposed in various parts of 
 the trunk." 1 Of this class, Dr. Carpenter adds, " Generally 
 speaking, the nervous system bears but a small proportion to 
 the -whole mass of the body ; and the ganglia which minister to 
 its general movements are often small in proportion to those 
 which serve some special purpose, such as the actions of 
 respiration." 
 
 Taking another step in advance, we come upon animals 
 distinguished by the arrangement of joints and adaptation of 
 muscles for a more free and varied exercise of locomotion. 
 This includes insects with legs and wings, and animals with 
 great locomotive power, such as centipedes. In the life of such 
 animals the nervous system is specially concerned with loco- 
 motion. As illustrated in the case of the centipede, the nerve 
 system " consists of a chain of ganglia connected by a double 
 cord, commencing in the head and passing backwards through 
 the body. The ganglia, though they usually appear single, are 
 really double, being composed of two equal halves closely 
 united on the median line." 2 
 
 By the next stage of advance we come upon animals whose 
 bodily organism is built up on a skeleton of bone, jointed 
 and bound together with strong ligatures, around which the 
 muscles are gathered, and the whole mechanism is controlled 
 by what is properly denominated brain. It is on this class 
 of animals that our interest chiefly concentrates for the pre- 
 sent, though by observation of the lower 
 orders we find the best opportunity for con- 
 templating the simpler and earlier phases ■, ' ■. 
 of reflex movement. 
 
 First I take the brain of a fish, the carp, 
 which is voracious and swift in movement, 
 being the example. 
 
 mi • t , Fig. 26. 
 
 lhe projecting lines are the tracts con- brain of the carp 
 nected with the organ of smell. The frontal (rmtwai size). 
 lobes (A), which are the hemispheres of the (Wrom JfttJ^ ° Kms 
 brain, are relatively small when brought into comparison with 
 the optic lobes (B), which here assume the appearance of the 
 1 Carpenter's Mental Physiology, p. 49. 2 lb. p. 51. 
 
126 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 chief feature of the entire nerve centre. Just behind these is 
 the cerebellum, assuming a defined and rounded form. From 
 this case it is obvious that special development of portions of 
 the nerve centre occurs in harmony with the development of the 
 special senses, and the amount of exercise assigned to them in 
 animal life. Thus the hemispheres are, in the case of the carp, 
 comparatively small, almost rudimentary, being little more than 
 ganglia, while the optic lobes are expanded to large propor- 
 tions. The same thing holds true in the brain of the cod, as well 
 as in other classes of the smaller-sized fishes, where swiftness 
 of movement, guided by acuteness of vision, is the chief 
 characteristic. Any one who has watched the habits of 
 fishes, as every angler on a stream is accustomed to do, is 
 well acquainted with the wonderful quickness of vision which 
 they display, making it next to impossible to keep out of their 
 sight when they lie in clear water. On account of this quick- 
 ness of vision in the fish, most anglers are content to abandon 
 their art when the rivers are clear and small. The more eager 
 of the fraternity betake themselves to the bank of the stream 
 to ply the lure after darkness has set in, fishing patiently and 
 successfully even when they are unable to see the artificial flies 
 they use. Others, who are specially patient devotees of the 
 gentle art, yet reluctant to abandon to the sport the usual 
 hours for slumber, are content, when waters are shallow and 
 clear, to resort to a stooping posture, to accept thankfully the 
 shelter of a well-placed rock, and to throw the longest possible 
 line, by all these expedients to keep alive the hope of some 
 measure of success in the attempt to catch a few fair specimens 
 of the quick-sighted trout or salmon. 
 
 Wright, a careful observer, and a distinguished aurist, makes 
 the following statements concerning the special senses in 
 fishes: — "With the exceptions I have just mentioned (these 
 are the skate and the whale species) fish possess no external 
 ear or tube to transmit sound," but they " possess the other 
 organisation of the sense of hearing." " Fishes have certainly 
 the senses of smell and taste ; the first very perfect." " There 
 can be no doubt but they have the sense of sight in great per- 
 fection, but some species have it more acutely than others." 1 
 1 Fishes and Fishing, pp. 82, 96, 99. 
 
v.] COMPARISON OF STRUCTURE AND FUNCTIONS. 127 
 
 I take next an example of brain found 
 among the reptiles, as illustrated by the /!%-— a 
 frog. 
 
 In this figure the protruding points in 
 front are the tracts connected with the organ 
 of smell ; the large frontal portion (A) repre- fig. 27.— bbain 
 sents the two hemispheres of the brain, quite , 0¥ THE FE0G (+ 2 >- 
 
 ■*■ . {From Ferrier's Fwnctwns 
 
 smooth, and without trace of convolution; of the Brain.) 
 the two round bodies immediately behind are the optic lobes 
 (B), indicating the prominence given to the organs of sight in 
 this form of animal life ; just behind these is the cerebellum or 
 little brain (C), appearing only in a small rudimentary form ; 
 and immediately behind that is the medulla connected with the 
 spinal cord, which last is in all animals similar in structure. 
 There are here three points deserving special remark : the great 
 importance of the brain as the grand central organ of the 
 nerve system, the greater bulk of the hemispheres towards 
 the rear than towards the front, and the importance assigned 
 to vision as indicated by the relative size of the central lobes 
 connected with the organs of this sense. In accordance with 
 these features are the known characteristics of the animal, 
 which takes its forward leap by the action of the hind limbs, 
 and is, even in the twilight, singularly quick in vision. 
 
 I pass next to birds, taking the pigeon as the example, on 
 account of it happening to be the bird which has been most 
 under observation of those who have devoted special study to 
 the histology of brain. 
 
 In the following example of the nerve centre, we see the pre- 
 ponderance of the brain proper in the larger ^ 
 proportions of the hemispheres (A) relatively 
 to the other parts. There is at the same time 
 a fuller development of the cerebellum, or 
 little brain C, which shows the laminated form, 
 which is its familiar feature as we ascend 
 the scale. In both these respects the brain 
 of the pigeon affords a better illustration fig. 28.— brain of 
 than either of the preceding of the normal ™ ^ j££ 
 arrangements and proportions of the several 0/ tu Brain.) 
 parts. Further, in respect of arrangement, it is to be observed 
 
12? THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 that the optic lobes, the one marked B, and the other in a simi- 
 lar position on the other side, are not seen lying between the 
 brain proper and the little brain, as in former examples ; but 
 the cerebrum and cerebellum are brought into close relation, 
 after the analogy of what is recognised higher up the scale. 
 The optic lobes appear as if at a transition period in the course 
 of development, — I might say, appear as if they were on their 
 way for being covered, and concealed underneath, by the fuller 
 development of the cerebrum. If development proceed after 
 the analogy indicated by the three illustrations now before 
 us, we shall have to seek the optic lobes underneath, and not 
 in a conspicuous place within the superficial area of the nerve 
 centre. And this, we know, actually happens as shown when 
 observation is extended up the scale of animal life. 
 
 Directing attention now on the special aspects of the brain 
 in the pigeon, as these bear upon the life with which it is 
 connected, there are several points deserving attention. As to 
 the brain proper, it is still a smooth brain, with no trace of 
 convolutions. It does not bear external marks of subdivi- 
 sion, further than is implied in the division into hemispheres ; 
 and thus does not suggest the government by its means of a 
 complex organism. Further, though we cannot speak of lobes, 
 it is to be observed that the frontal region is narrow, and that: 
 the great mass of the brain is towards the back region. In this 
 respect it stands in direct contrast to the human brain. Next, 
 we must remark the relative insignificance of the olfactory 
 tracts. They do not altogether disappear, their position is 
 still indicated at the front of the hemispheres, but they are 
 not conspicuous as are the projecting tracts seen in the frog 
 and in the fish. 1 This animal is one not directed by the 
 organ of smell, as a dominant power in its life, though the 
 sense of smell clearly plays its part. On the other hand, 
 the optic lobes are prominent, and from this fact the natural 
 inference is, that the animal is guided much more by the 
 sense of sight than by smell. At this point we are touch- 
 ing upon a general and well-recognised characteristic of birds, 
 as they sweep through the air, flit from branch to branch, or 
 
 1 This is well indicated in Professor M'Kendrick's figure, Outlines of 
 Physiology, p. 505. 
 
v.] 
 
 COMPARISON OF STRUCTURE AND FUNCTIONS. 
 
 129 
 
 alight with precision on a slender twig. Within the brain and 
 cerebellum there is power for control of the entire organism 
 and co-ordination of movement on both sides; but vision is 
 the sense which is the true regulating power for all the 
 movements. 
 
 I pass now to another and very different phase of.life, as 
 illustrated in the case of the smaller quadrupeds, known as 
 the Eodents. 
 
 Fig. 29 (2). 
 
 Flo. 29.— BRAIN OF THE EAT— UPPER VIEW, AND SIDE OF RIGHT 
 HEMISPHERE (natwral). 
 
 (From Ferrier's Functions oftha Bram.) 
 
 In this case the brain is more elongated, less expanded, and, 
 by the difference of shape, suggests adaptation to a body of 
 different form, and subject to conditions of locomotion quite 
 distinct. The brain is still quite smooth, without trace of 
 even rudimentary convolutions, thus indicating that the grey 
 matter requisite for innervation of the fibres spread over the 
 body can be accommodated within the area of the skull, 
 without doubling or folding of the mass. Whether more 
 may be involved in the convolutions of the grey substance 
 where these appear, such as mental or intellectual action, 
 I do not here inquire ; but it is admitted that convolution 
 -provides an increased surface, and by so doing may supply an 
 increased degree of nerve force requisite for a more compli- 
 cated arrangement of nerve fibres. We may, therefore, reason- 
 ably infer from the appearance of a smooth brain, that the 
 requirements of animal life in the case under observation are 
 provided for without convolution, that is, without any increase 
 in the amount of cellular matter beyond that easily stored 
 within the cranium. 
 
 1 
 
130 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 The marked contrast between this brain and that repre- 
 sented in the figure 28, apart from diversity of shape, is the 
 conspicuous place assigned to the olfactory tract. This is 
 shown in the front view, by the two bulbs protruding in front 
 of the hemispheres ; and in the side view, by the long broad 
 tract, which passes backwards from the front bulb along the 
 under region of the brain. The optic tract is present, and has 
 its own share of influence, but it is not conspicuous. In the 
 comparison of these two forms of special sense, sight and smell, 
 this case is exactly the reverse of what is found in the 
 pigeon. The bird is guided in all its movements more by 
 sight than by smell ; the rat is guided more by smell than by 
 sight. 
 
 The numbers seen on the figures represent, under Professor 
 Ferrier's experiments, the same results as were obtained from 
 stimulation of those centres which are similarly numbered 
 on the brain of the monkey, and described in the preceding 
 chapter. This explanation also applies to the subsequent 
 figures which have numbers on the surface. 
 
 Next in order, as presenting a large example of the rodent 
 type of brain, I take that of the rabbit. 
 
 In this case we have the same characteristics as in the former. 
 There are the smooth brain, the well-formed cerebellum, and 
 very conspicuous the olfactory bulb in front, with the strong 
 tract proceeding underneath to the rear of the brain. .The brain 
 is still of the same elongated form as in the preceding case, 
 but a greater proportionate depth is apparent forward in the 
 organ, which does not slope away to the front so sharply as is 
 the case in the brain of the rat. The optic tract is to be 
 
 sought concealed in the 
 under region of the brain. 
 But the organ of smell is 
 the determining power in 
 the midst of all the sen- 
 sibilities and activities of 
 
 Fio. 30.-BRAIN OF THE RABBIT-SIDE VIEW .-. ; ,, yr rm,. 
 
 of the left hemisphere wlb animal s me. X110 
 
 (natural). harmony of this with the 
 
 (From Ferrier's FvMctiom tft* Brain.) We ll-knOWn habits of the 
 
 rabbit will be at once recognised. As the animal sits up 
 
v.] COMPARISON OF STRUCTURE AND FUNCTIONS. 131 
 
 on its hind quarters, its sensitive nostrils twitching inces- 
 santly, while it sniffs the air, the rabbit is a most striking 
 example of an animal instructed and regulated by its nose. 
 If we may venture upon conjecture as to the animal's ex- 
 perience, we may well fancy that that experience is largely 
 made up of a series of smells, though not exclusively so, as 
 in the imaginary case suggested by Mr. James Mill, 1 in which 
 an animal might be supposed to have no organ but that of 
 smell; for here the other senses are active for the guidance 
 of the animal, though less powerful. And even when we speak 
 of the sense of smell as providing the chief elements of experi- 
 ence, we need to keep in view the regular effects of organic 
 action in all animal life, leading to common experience and 
 common results under guidance of whatever sense happens to 
 be the most acute. 
 
 Continuing the line of ascent up the scale of animal life, we 
 make the transition to convoluted brains, which still retain the 
 prominent olfactory tract. 
 
 On looking at fig. 31, it will at once be remarked, apart 
 from the convolutions, which at first are apt to absorb the 
 attention, that a considerable change of shape is appearing as 
 we advance. There is still the elongated form remarked upon 
 when the transition was made from the bird to the rat. But 
 there is here considerably more rilling up towards the frontal 
 region, and consequently some approximation towards round- 
 ness. With this altered shape must be connected a reference 
 to size and superficial area. The size is very decidedly larger, 
 much more so than can be explained by reference to the com- 
 parative bulk of the body in the case of the rabbit and cat. 
 At the same time it must be remarked that the increased 
 size is obtained by development of the organ towards the 
 front, not towards the back. This consideration has the 
 more importance, because afterwards we shall see develop- 
 ment proceeding, so as to cover the cerebellum, which is 
 still exposed here. We have undoubtedly, in the example 
 now before us, a more important brain for a more important 
 life. Eeference to the results of domestication in the case of 
 the rabbit and the cat confirms and illustrates this superiority 
 
 1 Analysis of the Human Mind, vol. i. p. 13. 
 
132 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 in the life of the latter. When to size we add the enlarged 
 area of the grey matter obtained by the variety of convolutions, 
 
 Pro. 31.— BRAIN OF THE CAT— LEFT HEMISPHERE (natural). 
 
 (From Ferrier's Functions of the Brain.) 
 
 " Left hemisphere of the brain of the cat. a. The Assure of Sylvius, b. The crucial suIcub. 
 o. The olfactory tract, cut. i. The superior external convolution, u. The second external 
 convolution, m. The third external convolution, ir. The fourth external convolution." 
 
 the increased complexity of the organ is still more obvious, and 
 the inference to superiority of life has additional support. The 
 brain in this case is advanced in form, size, and complexity of 
 structure. I do not here stay to prosecute inquiry as to the 
 higher features of life discovered by observation of the animal's 
 actions. Without resorting to any particularity of investiga- 
 tion, it is well known that the cat has a far more energetic and 
 concentrated use of muscular powers in the catching of its 
 prey, whether that be the mouse, or the smaller form of bird, 
 which escapes from danger by instant flight, than the rabbit, 
 which trips out from its cover, bobs along among the grass or 
 turnips, nibbling at its food just where it halts ; and which sits 
 up on its hind quarters at sound of approaching footstep, trips 
 back again to cover, and there lies in shelter until complete 
 quiet reigns around. A further test in the comparison is 
 obtained when we consider the difference of result in the 
 history of the two animals under domestication. This appears 
 in the larger amount of human influence which can be brought 
 to bear upon the cat than upon the rabbit. We are accus- 
 tomed to speak of the want of " affection " in the cat as 
 contrasted with the dog, and this may be connected with a 
 lower degree of "intelligence;" but every one will admit 
 
v.] COMPARISON OF STRUCTURE AND FUNCTIONS. 133 
 
 that very much more can be made of a young cat than 
 of a young rabbit when brought daily under the influence of a 
 household. 
 
 Looking now somewhat more closely at the cat's brain, we 
 observe that the olfactory bulb is still a prominent object. 
 Only a section of it appears in the figure, but the relative 
 thickness of that is enough to show its importance. Yet it is 
 not relatively so important as in the rat and rabbit ; and does 
 not appear with projecting points or bulbs so far advanced 
 beyond the frontal region of the brain as in preceding ex- 
 amples. The most marked advance in this brain is the sub- 
 division, which appears both in fissures and convolutions. 
 Springing from the floor of the brain, and running backwards 
 into the substance of it, is the Sylvian fissure (A), exactly 
 similar in position and course to the same fissure in the human 
 brain. By this the organ is divided into front and back regions. 
 There is no such fissure as that of Rolando, but at a point con- 
 siderably in advance of the position where we should have 
 looked for it, (B), is a fissure named the crucial or frontal 
 sulcus. Next, it will be observed that there are four leading 
 convolutions, marked by the first four Roman numerals ; and 
 these do not take the course familiar in the human brain, but 
 run backwards longitudinally, and double round in rear of the 
 Sylvian fissure. By this succession of convolutions there is 
 a much more complicated arrangement of the grey matter, and 
 along with this must be connected the fact that a much larger 
 number of centres is marked on the figure, as responsive to 
 electric stimulation. These, indeed, are so numerous, that, so 
 far as such testimony bears upon the point, we may say there 
 is a very decided approximation to what is found in the brain 
 of the monkey. 
 
 From this example I proceed to that of the dog, with which 
 some acquaintance has already been obtained. 
 
 This brain is obviously on the same model as that of the cat, 
 but is larger, and is more fully developed both in the frontal 
 region and behind. It is still of the elongated shape remarked 
 upon in previous cases, and which appears to be characteristic 
 of all animals which habitually run upon four legs, for there 
 seems to be some adaptation in the form of the organ to the 
 
134 
 
 THE RELATIONS OF MIND AND BRAIN. 
 
 [chap. 
 
 formation of the body which it controls. In harmony with its 
 shape, the convolutions are first seen to run in a longitudinal 
 direction, and then to circle round the Sylvian fissure, after the 
 manner observed in the previous figure. The great leading 
 convolutions are also four in number, but are more fully 
 formed, and more clearly distinguished throughout their course. 
 
 Fig. 32.— BRAIN OP THE DOG-LEFT HEMISPHERE. 
 (From Ferrier's Functions of the Brain. ) 
 
 " Left hemisphere of the brain of dog. a. The fissure of Sylvius, b. The crucial sulcus. 
 o. Tho olfactory bulb, i, n, m, iv indicate the first, second, third and fourth external 
 convolutions respectively." 
 
 The Sylvian fissure (A) occupies a position exactly analogous ; 
 but the crucial or frontal sulcus (B) is farther back on the 
 brain, or perhaps its position might be more accurately indi- 
 cated as nearly the same, but with a considerably larger 
 amount of brain substance in front of it. Quite a prominent 
 feature here is tho large olfactory bulb in front, with its strongly 
 developed tract running backwards, and becoming still more 
 enlarged before it disappears underneath, at the region where 
 No. (15) is placed. It is impossible to look upon the provi- 
 sion for the organ of smell without concluding that it has a 
 large influence in the animal's life. 
 
 When from external configuration we proceed to the in- 
 ternal structure of this brain (fig. 33), it will appear that there 
 is a close resemblance to what has been found in the human 
 brain. 
 
 Within the dog's brain is found the strong connecting band 
 
v.] COMPARISON OF STRUCTURE AND FUNCTIONS. 135 
 
 {corpus callosum) which unites the two hemispheres, and con- 
 nects, different portions of the grey matter on the two sides. 
 In this figure the hemispheres are represented as drawn aside ; 
 the connecting band has been cut away, its edge appearing 
 just where the superficial convolutions close (11); and the 
 internal structure of the organ is shown, along with the aspect 
 of the cerebellum when seen from above. A glance at this 
 
 Fio. 33.— INTERNAL STRUCTURE OF THE BOG'S BRAIN. 
 (From Ferrier's Ftmotvms of the Brain.) 
 
 "The Cerebral Hemispheres of the Dog separated after Division of the Corpus Callosum, so as 
 to expose the Ventricles and Basal Ganglia. 1. The internal surface of the left hemi- 
 sphere. 2. The corpuB striatum. 3. The optic thalamus. 4. The anterior tubercles 
 of the corpora quadrigemina. 5. The posterior tubercles. 6. The anterior pillar of 
 the fornix, which is divided on the left, undivided on the right side (12). 7. The third 
 ventricle, exposed by drawing the optic thalami asunder. 8. The upper surface of the 
 cerebellum. 9. The olfactory bulb or rhinencephalon. 10. The anterior commissure. 
 11. The corpus callosum divided. 12. Fornix, undivided. 13. The soft commissure. 
 14, The pineal body, situated over and concealing the posterior commissure. 15. The 
 descending cornu of the lateral ventricle." 
 
 figure at once reveals great similarity of internal structure 
 with that of the human brain, and large development of the 
 little brain. 
 
 Looking first at the two main constituent parts, marked on 
 the left side (2 and 3), and taking these with the analogous 
 parts on the right side, we have the two great basal ganglia or 
 bands of nerve fibre — the one (2) being the corpus striatum, com- 
 
. 136 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 posed mainly of motor nerves ; the other and lower (3) being 
 the optic thalamus, composed chiefly of sensory nerves ; and 
 just in the middle behind this, the four rounded bodies, which 
 are the optic lobes (corpora quadrigemina), of which the two 
 in front are the anterior tubercles and the two in rear are the 
 posterior tubercles, while in advance of these is the pineal 
 body. 1 
 
 The results of comparison of the external acd of the internal 
 structure of the dog's brain with the analogous features of 
 man's brain are quite different. The external configuration 
 of the dog's brain with its elongated shape and longitudinal 
 convolutions, differs altogether from that of the human brain. 
 The appearance and arrangement of the basal ganglia are, how- 
 ever, quite homologous with all that is found in the human 
 brain. In this way it becomes obvious, as we ascend the scale 
 of animal life, that though there is considerable diversity in the 
 figure of the brain, and in the manner in which the grey 
 matter is packed within the skull, the internal structure, 
 consequent on the grouping or massing of the nerve lines, is 
 wonderfully like to the structure of the human brain. The 
 resemblance in this latter respect is even so exact that the 
 dog's brain might be employed to illustrate the internal 
 arrangement of man's brain. If we take the terms analogy and 
 homology in the sense given by Professor Owen, the one to 
 represent functional resemblance, the other structural resem- 
 blance, we must grant that the internal structure of the dog's 
 brain is homologous with that of man. This result is in obvious 
 harmony with what has been established as to the two sets of 
 nerve lines, sensory and motor, and their relation to the nerve- 
 centre. Every living organism, endowed with sensibility and 
 power of locomotion, must have its lines of sensory and motor 
 nerves, and these must have their supply of nerve energy by 
 direct communication with the grey matter of a nerve centre. 
 The essential feature of the grey matter is not discovered by 
 reference to the manner in which it is laid up in the skull, or 
 the direction given to its folds, but in the cellular nature of the 
 tissue. But sensory nerves must be gathered from all parts, 
 
 1 For comparison with the human brain, reference may be made to Fig. 11, 
 page 32. 
 
v.] COMPARISON OF STRUCTURE AND FUNCTIONS. 137 
 
 and motor nerves must be distributed to all parts. This being 
 essential to all physical life as known to us, there must be 
 a certain degree of analogy at least between the structure of 
 lower and higher forms of animal life. And as we rise in the 
 scale to higher orders, there must be close resemblance of 
 internal structure, if the two different sets of nerve lines and 
 the nerves of special sense are to be grouped together in direct 
 contact with the grey matter of the nerve centre. 
 
 With so many and varied orders of dogs as we have, differing 
 greatly in size, it is impossible to have a figure of a typical 
 brain which can be taken as a guide to the relative size of the 
 organ. But looking simply at the external aspect of the dog's 
 brain, it is clear that the increase structurally, as compared 
 with the brain of the cat, consists in addition to the frontal 
 region, and increased elevation behind, but still without such 
 enlargement in the latter region as to cover the cere- 
 bellum. 
 
 Thus we have in this case a still more important brain 
 before us than that of the cat. In accordance with this, it will 
 be readily allowed by all that we have superior intelligence in 
 the dog. This superiority appears in so many ways that it 
 becomes difficult to give, within a brief space, a satisfactory 
 summary of its evidence. Volumes can be filled with illustra- 
 tions of the sagacity of the dog. One has only to refer to the 
 author of Bab and Ms Friends for abundant and very varied 
 testimony to the depth of human interest which may be felt in 
 the dog. 1 So far as I can judge, the dog has a degree of 
 intelligence quite unknown in any other animal, and conse- 
 quently it is more the companion of man than any other, for it 
 is a real companionship which subsists between the dog and 
 his master. Left to itself, the animal has its low side, and if 
 it know nothing in life but what we may call " self-direction," it 
 may soon be regarded by us as " a vile dog" or "a low cur." 
 But in companionship with man, and under his direction, it 
 is not only active, as it is in almost all circumstances, but 
 affectionate, discriminating, sensitive to a degree unknown in 
 the case of other animals, and even noble in bearing, though 
 
 1 Rab and his Friends, by John Brown, M.D. 
 
138 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 this last quality depends greatly on training, and is easily 
 lost. 
 
 What was said concerning the cat, as to the use of its 
 muscular powers in pursuit and mastery of prey, may be said 
 with increased force as to the dog. The possibility of such 
 energy as a dog displays in pursuit of a hare, or fox, or in 
 tearing up the hiding-place of a rat or a rabbit, implies a high 
 degree of brain development, for it is not mere celerity of 
 movement which is observed, but great muscular effort, which 
 requires not merely controlling power over motor nerves, but 
 abundant supply and free use of a large amount of nerve 
 energy in order that the muscular system may be exerted 
 with so much force. In this consideration alone we have 
 one large part of the physiological explanation of increased 
 mass of brain in the dog, in comparison with smaller ani- 
 mals which fall victims under its attack. Strength of 
 muscle and evolution of nerve energy must keep pace with 
 each other. 
 
 But it is characteristic of the dog that it can be turned aside 
 from pursuit of prey and led into a different form of life, 
 without abatement of the energy displayed in what may be 
 called the "more natural form of life." And here it is we 
 come upon the evidence of greater intelligence, for it is when 
 the dog comes under training that we find the true measure of 
 the higher power belonging to the animal. It can be trained 
 to a degree of self-restraint quite unknown in the case of the 
 cat, and unapproached, so far as I have gathered, by any other 
 animal which has come under continued influence of man. 
 The clog will indeed steal when he has opportunity of such 
 a kind as implies the entire absence of his master's control, but 
 he will not steal with the promptitude and consummate cool- 
 ness of the cat. The difference of the two animals in this 
 respect arises largely from these facts, that the dog is much 
 more sensitive than the cat, and is in some respects more 
 liable to continued punishment (for the cat is not trained to 
 obedience by the castigation which is common in the dog's 
 life) ; and much more submissive, seldom risking the attack 
 upon his .offended castigator, which the cat would very readily 
 attempt. 
 
v.] COMPARISON OF STRUCTURE AND FUNCTIONS. 139 
 
 Beyond this, the intelligence, along with the affection of the 
 animal, is great. I need not here enter into details as to the 
 large appreciation of design shown by the dog trained to point 
 or set when his master is in pursuit of game. The facts are 
 familiar, and the testimony they involve unquestionable. Even 
 more remarkable in many ways is the intelligence of the sheep- 
 dog, which is the daily assistant of man all the year round, 
 and is not kennelled and fed and exercised for months in 
 prospect of a special service required only for a limited period 
 of the year. The "collie" will receive orders, and proceed 
 alone far up the hill-side in execution of them. When thus 
 far removed from his guide, he will interpret such signs as 
 whistling, calling, and gesticulating, and will at once proceed 
 to the execution of the fresh orders so " telegraphed," perhaps 
 I should say " telephoned." Analogous to this is the conduct 
 of the noble breed of "St. Bernard dog," — those powerful 
 brutes which come rushing out from the Hospice, the whole 
 pack bellowing in a manner sufficiently alarming, and which 
 at once distinguish between the peasant and the traveller, 
 quietly recognising that the latter is privileged with " right of 
 entry," though he has never been seen on the mountain before. 
 When one of these animals goes forth with a monk over the 
 winter's snow, bearing round his neck supplies for the needy, 
 he courses hither and thither in full understanding of his 
 master's purpose, differing widely from that of him who is 
 "bewildered in pursuit of game." Scenting on the breeze 
 enough to direct an animal which is guided more by his nose 
 and olfactory, bulb than by any other brain centre, he hurries 
 onward, and, reaching the spot he seeks, speedily makes the 
 snow fly behind him as a minor cur would the sand of a rabbit- 
 warren, and there discloses the human form threatened with 
 an icy grave. 
 
 Of all animals the dog is the one capable of receiving 
 most from human influence, and consequently most sensitive 
 to the indications of human affection or displeasure. There is 
 no animal dies so readily from neglect as a dog which has 
 found the daily pleasure of life in attending his master and 
 executing his commands. Besides the well-known examples 
 
140 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 of strong affection, such as that of a dog stretching himself on 
 his master's grave, and refusing to be enticed away, as in the 
 case of the dog celebrated in the annals of Greyfriars' Church- 
 yard in Edinburgh, known as " Greyfriars' Bobbie," we have 
 many examples of extreme suffering under a master's displea- 
 sure. I have known two very striking cases of the speedy 
 death of a dog under grief. In one case narrated to me 
 by the owner of the animal, a dog had occupied itself, when 
 the family were absent at church, with pursuing and killing 
 the poultry belonging to the household. After having killed 
 them, it carefully buried them one by one in different parts 
 of the garden, in which the pursuit and slaughter had taken 
 place. Shortly after the return of the family, the absence 
 of the hens was remarked. A search was made, but no trace 
 of them could be found either about the premises or in 
 the neighbourhood. At length the attention of some one 
 was arrested by evidence of the ground in some parts of 
 the garden having been disturbed. The soil was turned up, 
 and the hens' bodies were found. The dog was taken to the 
 garden, and immediately confessed his guilt. His master took 
 him to his library, and, having shut the door, began a repri- 
 mand after this fashion : " What a wicked thing you have done 
 in murdering the hens ! You are a minister's dog, and should 
 have been an example to other dogs, instead of doing such a 
 thing as this. Then, this is Sabbath-day, and the deed is all 
 the worse on account of the day on which it has been done." 
 Thus admonished, the dog was put out at the door, and the 
 door shut. Next morning he was found dead. A coroner's 
 inquest was not held, but a veterinary surgeon was consulted, 
 and he gave the verdict, " Died of a broken heart." He said 
 had the animal been well, punished, and then received into 
 favour again, all would have been right ; but he could not bear 
 to be treated as an outcast. 1 
 
 From the brain of the dog I pass to that of the horse, another 
 
 1 I am indebted for this narrative to the owner of the dog, the Rev. Dr. 
 Robertson of Irvine, distinguished equally for bis high appreciation of art 
 and his power in preaching the gospel ; and known to all his friends as one 
 peculiarly fond of animals. 
 
v.] , COMPARISON OF STRUCTURE AND FUNCTIONS. 141 
 
 animal which, has a large share in the interest of man, and also, 
 comes very much under human influence. 
 
 Fig. 84.— BRAIN OF THE HOESB— EIGHT HEMISPHERE. J 
 (After example in the Atlas of Leuret and Gratiolet.) 
 
 Here we have a beautiful example of brain structure. The 
 shape is still of the elongated form seen in the cat and dog ; 
 the cerebellum is still uncovered, lying open to view in the rear 
 (Cm) ; but the advance in development of brain is striking and 
 important. The convolutions are peculiarly fine. They are 
 still so far longitudinal in arrangement, as seen in previous 
 examples. This will appear by reference to the convolutions 
 1, 11, in, and iv. But there is more appearance of the ascend- 
 ing form of the frontal region, with grouping of subdivisions in 
 the rear ; and each convolution is much more distinguished by 
 twisting of its substance than in the case of the cat, or even of 
 the dog. The Sylvian fissure (S) is conspicuous as in other 
 examples ; but the convolutions are not simply folded round it, 
 in the manner recognised in the two preceding cases. The 
 doubling or twisting, which is a marked feature here, illustrates 
 quite decisively the rule that by this method provision is made 
 for storing a larger amount of the grey matter, and exposing its 
 surface for supply of nourishment carried through the blood- 
 vessels of the pia mater. 
 
 Looking along the lower portion of the figure, we have illus- 
 tration of the special and general arrangements of the connected 
 nerve system. In front there is the prominent olfactory bulb 
 
142 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 (pi), with its distinct nerve tract running back underneath the 
 grey matter, showing a high degree of importance assigned to 
 smell in the government of life. Half-way along appears a 
 section of the optic nerve (op), cut at the point where it is 
 seen entering within the central region. Still farther to the 
 rear, and underneath the brain, is seen the bridge (P) ; the 
 medulla (M) ; and the nerve band (Sp) proceeding towards the 
 spine. 
 
 The horse is an animal so well known, and so constantly 
 rendering service to man, that we are able to form a decided 
 judgment as to its " intelligence." Beyond doubt, it stands 
 high among the animals for intelligence, as that is illustrated 
 by capacity for training. It soon adapts itself to the use of 
 harness, and the requirements for being yoked to a carriage ; 
 it readily recognises the wishes, and even the peculiar habits of 
 its driver ; it shows great tenacity of memory as to locality, 
 going by marked preference in a direction with which it is 
 familiar. We have not in the case of the horse so many 
 special features of attainment as we have distributed amongst 
 the various breeds of dogs. But we are not without examples 
 of special attainment. Such an example is given in the train- 
 ing for cavalry service in our army. The animals, as well as 
 the soldiers, need to be trained to the evolutions belonging to 
 cavalry drill ; and they quickly attain familiarity with these, 
 wheeling into position as required. No doubt they are aided, 
 not only by the movement of the reins, but by the muscular 
 strain of the limbs of the rider, as he inclines in the pre- 
 scribed direction. Nevertheless it is beyond doubt that the 
 horses themselves come to recognise the bugle call, and asso- 
 ciate it with the movement required. Our regiments of 
 yeomanry cavalry afford a good illustration. Animals previ- 
 ously accustomed only to ordinary saddle exercise, and others 
 familiar only with the common round of harness work required 
 in agricultural pursuits, learn the military evolutions so well 
 before two weeks of the drill are over, that their riders in many 
 cases firjd their chargers moving in the required direction 
 before they are aware of having indicated it by a movement of 
 the reins. The wonderful feats of selected animals reserved 
 for training with a view to public exhibition afford a striking 
 
v.] COMPARISON OF STRUCTURE AND FUNCTIONS. 143 
 
 addition to the evidence we have of the horse's power to appre- 
 ciate his rider's purpose. 
 
 In so far as we observe the self-directed movements of the 
 horse, it is ohvious that he is guided chiefly by sight and smell, 
 and of the two senses, chiefly by the latter, in cases where 
 objects appear strange to him. After he has looked at the 
 object for a time, he will approach nearer, and then advancing 
 to it, will bring his nostrils into contact with it, and if there 
 be nothing in the object specially offensive to his sense of 
 smell, he is contented. His interest in the object is at an end, 
 and he no longer gives signs of nervous concern at its appear- 
 ance. These facts harmonise with the prominence of the 
 olfactory tract and bulb shown in the figure of the horse's 
 brain. In cases of uncertainty of movement, such as are 
 encountered in a very dark night, the horse, by the combined 
 use of both senses, has the advantage over man. Hence it is 
 that, in such circumstances, the rider familiar with his horse 
 will lay the reins loose on his neck and trust to his guid- 
 ance, rather than attempt to guide him. Many examples are 
 recorded in proof of the wisdom of this course. I give a single 
 instance of the horse's quickness in detecting danger. The 
 incident occurred in the experience of a relative of my own 
 when travelling in South Africa, at the outbreak of one of 
 the Caffre wars, and all the particulars of which I heard from 
 his own lips, as they were afterwards published by him. 
 
 "It now became exceedingly difficult and even dangerous either 
 to walk or ride, because the path was very wet, and often nearly 
 precipitous. I now changed my horse again, taking a smalt 
 pony, too spirited for such a time, but I could better trust his 
 sureness of .foot. In order to avoid a part of the road which I 
 knew would be impassable that night, we turned out of the 
 usual line, and in the darkness lost our way. I knew we were 
 approaching somewhere the summit of the mountain, and was 
 beginning to feel a little anxious, when suddenly my horse 
 reared, almost unseating me from the saddle. I spurred him 
 to go forward, but he reared again, and sprang violently back, 
 so that I could scarcely keep my seat. At that moment a 
 vivid flash of lightning illumined the country round ; and what 
 did I behold ! I was in the act of forcing my horse over a 
 
144 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 tremendous precipice, the height of which I cannot with cer- 
 tainty tell. It was near the summit of a high mountain, and 
 the descent is nearly precipitous to its base." * 
 
 In attempting to estimate the comparative intelligence of 
 the dog and horse, it seems impossible to rank the horse as 
 equal to the dog. Here, however, it becomes desirable to have 
 a clear test of the degree of intelligence in animals. Such a 
 test is not readily found by attempting to construct a theory of 
 what may be called " the intellectual acts " in the life of an 
 animal — a kind of minor mental philosophy, applicable to the 
 higher orders of animals. The inner life or experience of the 
 animal is too thoroughly beyond the reach of observation to 
 make such attempts safe. A more hopeful, but still very per- 
 plexing, line of inquiry is found in the endeavour to distinguish 
 between what we may still call "instinct," 2 and what may pro- 
 perly be recognised as in advance of that, and accordingly may be 
 designated " intelligence." If we take the observed actions of 
 animals as affording the data, setting on one side those which 
 are reflex actions, including under this designation those which 
 are spontaneous, that is, prompted by the functional activity 
 of certain organs, as in the ordinary search for food ; setting 
 on the other side actions implying some appreciation of the 
 adaptation of means to ends, we open up a most interesting 
 line of inquiry. Such inquiry must involve extremely deli- 
 cate and doubtful points of discrimination; but it is a most 
 promising method of investigation, by patient use of which 
 great service may yet be rendered to science and philo- 
 sophy. But some more simple and direct test is wanted, and 
 this, I think, is found in the results of training, when an 
 animal is brought under the influence of man. This does not 
 give by any means a complete and exhaustive test, but it is a 
 reliable and ready mode of comparison, to which I purpose 
 mainly to resort. We must indeed supplement the results of 
 man's training by reference to what the animal attempts in its 
 natural state. " The education test " is in a large degree appli- 
 
 1 Calderwood's OaJ'res and Caffre Missions, pp. 190, 191. 
 
 2 Professor Bain well defines Instinct— " Untaught ability to perform 
 actions." — Senses and Intellect, p. 2G1. To this may be added, unreasoning 
 performance of useful actions. 
 
v.] COMPARISON OF STRUCTURE AND FUNCTIONS. 145 
 
 cable to animals, as well as to the individuals of the human 
 race. With this we may find some clew through the labyrinth, 
 while many of its recesses are left unexplored. 
 
 There are certainly no two animals to which the test can be 
 more unreservedly applied than it can be to the dog and the 
 horse — those two most familiar attendants and servants of the 
 human race over a large portion of the globe. Both show a 
 quick and wide appreciation of the purposes of man, and both 
 are constantly under observation. Nowhere along the scale of 
 animal life are we more favourably placed for comparison than 
 here. Comparison therefore should be careful and minute. If 
 additional reason were required for prosecuting comparison, it 
 is to be found in the need for supplementing those observations 
 which have been made by means of electric stimulation of the 
 brain, and for guarding our inferences which depend upon that 
 class of observations. For as it cannot fail to be remarked 
 that some animals are more easily obtained than others for 
 purposes of experiment, observations are naturally made on 
 certain classes of animals, while others are excluded from 
 observation. The horse is an animal upon which experiment 
 is not likely to be often attempted, whereas the dog is one of 
 the animals most easily made the subject of experiment. This 
 difference in the history of physiological experiment presents 
 a reason for carefully comparing the brain structure with the 
 evidence of intelligence presented by the two animals. The 
 question is this : If the brain of the horse be the more elabo- 
 rate in structure, as illustrated by the elaborate arrangement of 
 its convolutions, is the horse in like proportion more advanced 
 in intelligence ? I shall take the evidence as presented by the 
 animals under training. 
 
 There is something in the difference of appliances for training 
 the dog and the horse. The whip and the whistle of the dog- 
 tramer, the bit and leathern thong and whip of the horse- 
 trainer, when brought into contrast, tell their own tale. In 
 both cases there is an appeal to fear, as is shown by the pre- 
 sence of the whip, — a necessary appeal in all cases, if inclina- 
 tion is to give way to obedience, and that is the meaning of a 
 regulated life under control of man. Yet the less appeal 
 to fear the better. And, that we may not attach too much 
 
 K 
 
H6 THE RELA TIONS OF MIND AND BRAIN. [chap. 
 
 importance to the instrument of pain, it is needful to remember 
 that, if the whip be much more in the hand of the controller of 
 the horse than of the governor of the dog, it is used much 
 more as a reminder, by its mere touch, or movement over the 
 back, or by the sound of its crack in the air, to indicate the 
 need for maintaining or quickening the pace, or for exercising 
 watchfulness on some rapid descent, than for the infliction of 
 pain by way of compulsitor or penalty. It would, therefore, 
 be a mistake to argue from the almost constant use of the 
 whip in the management of the horse, that the horse must 
 possess a duller nature, and must show itself less intelligent. 
 In many forms of its use, the whip is merely a sign to the 
 horse, as a word is to the dog, or just as the reins on the neck 
 may be when swayed by the rider, with hardly a tug at the bit. 
 Two things, however, seem obvious when comparing the means 
 used for training and guiding these two animals, — there is more 
 appeal to sight in the case of the dog than in that of the horse, 
 while there is more appeal to the sense of touch with the horse. 
 The dog sees and appreciates far more the visible signs which 
 are made to it than the horse does, and in this we have evi- 
 dence of a more sharp and discriminating observation. The con- 
 stant use of bit and rein in the management of the horse shows 
 that he needs more uniform control and guidance. It should 
 be observed, however, that this is in part accounted for by the 
 fact that we exact from the horse a much more constant and 
 uniform exertion of his strength, as we yoke him to a carriage 
 and make him drag it along. In countries where the dog is 
 yoked and made to draw burdens, there is the same resort to 
 the sense of touch, by a dragging movement to one side or the 
 other, though not by appeal to the sensitiveness of the mouth. 
 In both cases there is a resort to force, which indicates that 
 an appeal to intelligence is insufficient. But the much wider 
 appeal to sight and hearing in the case of the dog gives clear 
 evidence in favour of superiority of intelligence. 
 
 There is much more of companionship with man in the life 
 of the dog than in the life of the horse. This arises in part 
 from differences of size, form, and strength. On these accounts 
 a considerable deduction must be made from the apparent 
 strength of evidence here as to superiority of intelligence in 
 
v.] COMPARISON OF STRUCTURE AND FUNCTIONS. 147 
 
 the case of the dog. Nevertheless, after this deduction has 
 been made, a large margin remains. If we bring into com- 
 parison a favourite dog and a favourite horse, and restrict our 
 inferences to the facts connected with direct companionship, it 
 is still clear that the balance is in favour of the dog. When 
 you go out from the house to a field where both happen to be, 
 both will meet you, both will show signs of pleasure at the 
 opportunity of doing so, and both will receive with marks of 
 attachment the articles of food which you carry to them. But 
 if you walk about the field, or go to work actively within their 
 sight, the dog will give many more marks of appreciation than 
 the horse will do. This is amply illustrated in the harvest- 
 field. When the reapers set to work, the dog will quite recog- 
 nise that the work is to be continuous, and, retreating to the 
 shelter of some of the cut grain, will lie down there, and, 
 though apparently half asleep, he will keep an eye open to the 
 progress of things, and at once detect the signs of intention to 
 stop work. The horse, on the contrary, even with harness on, 
 will eat away where he is left, will lift his head, indeed, as he 
 sees or hears the approach of some one, but will resume eating 
 without concern until the rein is grasped by his driver. No 
 doubt some allowance is to be made for the fact that the dog 
 goes home with his master and is there supplied with the 
 food which the horse finds before him in the field. But, even 
 making allowance for this, our attention is directed to the fact 
 that a closer companionship can be maintained between man 
 and the dog than between man and the horse. 
 
 The same result is reached when we consider the effects of 
 training in the two cases. The dog gazing up into his master's 
 eyes, watching his habits, and set to do many things which he 
 desires to be done, shows a power of appreciation quite un- 
 known in the history of the horse. The range of work is greater 
 in the one case than in the other, and the dog can be far more 
 left to himself in the execution of an order than the horse can. 
 There is nothing in the work of a horse to rival the work of 
 the pointer or of the sheep-dog. The "collie" presents the 
 contrast in the most striking light, for the dog is intrusted 
 with the government of other animals, under direction from 
 his master, and shows himself equal to the task. 
 
148 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 The conclusion is confirmed by reference to training of the two 
 animals in what may he described as unnatural action, without 
 using the word unnatural in a condemnatory sense. I refer to 
 the results which follow long training for purposes of exhibi- 
 tion. This is training to mimicry of human action. We have 
 illustrations in training the animals to walk on two feet, or to 
 dance to music. In both cases the results show more of sub- 
 mission to human authority than intelligent use of means 
 appropriate to a given end. And it is well known that the 
 results are attained only by long-continued and painful effort 
 to do what does not come within the scope of the natural 
 activity of the animal. When, however, such attainments are 
 acquired and exhibited, the impression made on the onlookers 
 is quite different. In the case of the horse, the feats are 
 regarded as astonishing, mainly on account of his great size, 
 and the muscular effort needful to accomplish what is done. 
 In the case of the dog, such feats are much more comical, and 
 readily come to be considered ridiculous, simply because the 
 animal has so much more sense, and is able to do so much 
 more nimbly and intelligently what is natural to it, that there 
 is apt to be a feeling of dislike to witnessing such constrained 
 movements. 
 
 On the evidence thus presented in outline, it seems clear 
 that the dog has a larger degree of intelligence than the horse. 
 The point of comparison relative to brain structure is thus 
 brought out distinctly. The state of the case is this : the 
 dog, with a brain less elaborate in its convolutions, shows a 
 higher degree of intelligence; the horse, with a more ample 
 and complicated series of foldings in the convolutions of the 
 grey matter, shows less intelligence. What bearing has this con- 
 trast on our inquiry ? Advance in intelligence and advance in 
 complexity of brain -structure do not keep pace with each 
 other. They are not correlated so as to harmonise. If it be 
 suggested that a great deal more has been done for the training 
 of the dog than for the training of the horse, this is, no doubt, 
 true. This consideration, however, does nothing to lessen the 
 contrast. It makes it more remarkable. More has been done 
 in the one case than in the other, because the one animal is 
 more capable than the other. But specially it is implied that 
 
v.] COMPARISON OF STRUCTURE AND FUNCTIONS. 149 
 
 development of intelligence has gone on in the case of the dog, 
 without leaving its impress on the structure of the nerve 
 centre to any such extent as to bear comparison with the brain 
 of the horse. 
 
 What account, then, can be given of the greater complexity in 
 the brain of the horse ? There is more extensive folding of the 
 convolutions than in any case previously under consideration ; 
 this implies a larger amount of cellular tissue packed within the 
 cranium. What account can be given of this increase ? If all 
 the folds of the dog's brain were drawn out, removing all trace of 
 the grooves, and spreading out the grey matter on the level ; 
 and if the same thing were done with the convolutions of the 
 horse's brain, the mass would be found much larger in the latter 
 case than in the former. Looked at first by longitudinal 
 measurement, each of the four principal convolutions in the 
 two brains will stretch to greater length in the case of the 
 horse than in that of the dog. Looked at laterally, there is 
 also considerable gain on account of the greater amount of 
 groove to be brought up to the level. Looking at each as an 
 organised whole, when the entire grey substance is packed 
 together as found in the living subject, the result is a much 
 more complex organism in the case of the larger animal. 
 Obviously the first part of the explanation lies in the simple 
 fact of the greater size in the one case than in the other. But 
 in connection with this, the most important element in the 
 explanation is the much more complex muscular system to be 
 controlled. This more highly organised nerve centre is the 
 regulating power over the much larger degree of muscular 
 force which belongs to the body of the horse. 
 
 From this example I pass to the brain of the Monkey. In 
 doing so it must be understood that a clear distinction is to be 
 drawn between the Monkey and the Manlike Ape. 
 
 If the monkey's brain (fig. 35) be compared with that of the 
 horse, it will be seen to be in one aspect inferior. It is a 
 brain of simple or unfolded convolutions. In this respect it 
 is analogous to the examples of smooth brain found in the 
 lower orders of quadrupeds, such as the rat and rabbit. On 
 the other hand, it is far removed from the brains of those 
 animals by the divisions of surface which distinguish it. Never- 
 
ISO 
 
 THE RELATIONS OF MIND AND BRAIN. 
 
 [CHAP. 
 
 theless it is wanting in the beautiful windings shown in the 
 brain of the horse. This fact should be noted as an essential 
 point of contrast. This is a new type of brain, but it is a 
 new type starting on the lowest level, — a smooth surface. It 
 is smaller than the brain of the horse, or of the larger dogs. 
 And if we may estimate the grey matter superficially by the 
 
 ..OL 
 
 TSL 
 
 Fin. 35.— BRAIN OF THE MONKEY (MACACQUE)— LEFT HEMISPHERE 
 {natural size). 
 (From Ferrier's Functions.) 
 A, the fissure of Sylvius ; B, the fissure of Rolando ; C, the parietooccipital fissure ; FL, the 
 frontal lobe ; PL, the parietal lobe ; OL, the occipital lobe ; TSL, the temporo-sphenoidal 
 lobe ; Fj, the superior frontal convolution ; F 2 , the middle frontal convolution ; F s , the 
 inferior frontal convolution ; sf, the supero-frontal sulcus ; if, the infero-frontal sulcus ; 
 ap, the antero-parietal sulcus ; AF, the ascending frontal convolution ; AP, the ascending 
 parietal convolution ; PPL, the postero-parietal lobule ; AG, the angular gyrus ; ip, the 
 intra-parietal sulcus; T 1( T a , T 3 , the superior, middle, and inferior temporo-sphenoidal 
 convolutions ; t lt t 2 , the superior and inferior temporo-sphenoidal sulci ; 0!, 2 , and 3 , 
 the superior, middle, and inferior occipital convolutions ; 1( 2 , the first and second 
 occipital fissures. 
 
 levelling up or spreading out of the folds, there is much more 
 to be extended in the case of the horse than of the monkey. 
 
 At the same time, even with its return to smooth surface, 
 it is so different in form that it may be said to be an entirely 
 new step in the course of brain development. It is as if it had 
 been planned on a new model. The basis of the difference, or 
 essential feature, in the new type, is seen in the fissures divid- 
 ing the structure into sections or lobes. This is a clear advance. 
 In the brain of the horse the convolutions are beautifully 
 doubled down, giving a series of folds coming in close suc- 
 cession. There is nothing resembling this here. There is, 
 however, not only the Sylvian fissure (A), but the fissure of 
 
v.] COMPARISON OF STRUCTURE AND FUNCTIONS. 151 
 
 Eolando (B), coming from above, and a third fissure (C) separ- 
 ating the parietal from the occipital lobe. By means of these 
 the brain of the monkey is divided into four lobes, after 
 the manner of the human brain, and which can be similarly 
 designated, the frontal, parietal, occipital, and temporo-sphe- 
 noidaL They are marked, outside the line of the figure, by 
 the letters FL, PL, OL, and TSL. Within each division 
 there are separate convolutions, and in the great central por- 
 tion, where the depth of the organ is greatest, these are laid 
 up in the ascending form (AF, AP, AG), after the model of 
 the human brain. But in the front and back lobes, which 
 •are here similar in size and form, they lie longitudinally, with 
 horizontal dividing lines (sulci) between. Another marked 
 feature here is the covering of the cerebellum by extension 
 to the rear of the main organ. There is thus a new form of 
 brain, and it is connected with a new form of body. The 
 adaptation of the body to a semi-erect posture, the capacity 
 for movement upwards, not by bounds, but by grasping one 
 resting-place after another, and the possession of arms and 
 hands, with fingers for clutching branches, according to the 
 requirements of the ascending movement just indicated, — all 
 imply a new and perfectly distinctive muscular system ; and 
 this in turn requires a more elaborate nerve system for its 
 management. This correlation of muscle and nerve is the key 
 to the advanced characteristics of the monkey's brain. 
 
 For purposes of comparison I give (fig. 36, p. 152) a view 
 of the same hemisphere of the human brain. 
 
 Here the two fissures, the Sylvian fissure and the fissure of 
 Eolando, are marked respectively S and B. The third fissure, 
 toward the occipital region, is, however, not clearly marked 
 on the surface of the human brain. The four lobes are marked 
 by the initial letters of their names, the frontal, parietal, occi- 
 pital, and temporo-sphenoidal. 
 
 When the monkey's brain is compared with man's, they are 
 found to have this in common, that the greatest superficial depth 
 is found in the central region. But this in man is far more 
 elaborately constructed. This, we may recall, is the region 
 completely occupied by the centres identified under electric 
 stimulation. These centres were found to be connected with 
 
152 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 tHe movements of the limbs, special movement of the hands 
 and feet, and movements of the muscles of the face, operating 
 along with the use of the special senses. Looking now at 
 the contrast between the appearance of the monkey's brain 
 and that of man, and founding our conclusion on the results 
 of electric stimulation, we may say that the monkey's move-* 
 ments must be analogous to those of man, but that human 
 movements concerned with the same parts of the body are 
 capable of being much more complex, involving more intricacy 
 in detail, and much greater amplitude of control. The well- 
 
 Pio. 36.— LEFT HEMISPHERE OF THE HUMAN BRAIN. 
 
 known contrasts in the two forms of life fully support the 
 inferences thus drawn. Carrying further the comparison of 
 the two brains, they differ most markedly in the front and rear. 
 These two portions are very similar in the brain of the monkey, 
 and they are both much inferior to the same portions in the 
 human brain. In the frontal region the protrusion of an olfac- 
 tory bulb disappears, and the frontal lobe of the brain itself is 
 developed. The front portion of the brain appears more folded 
 in the case of the dog, and still more in the case of the horse. 
 The posterior region is more distinctly formed than in the brain 
 of the dog and horse ; it is even more sharply marked off than in 
 the human brain. In this portion there is evidence of superi- 
 ority, which is further marked by the fact that the rear or occi- 
 pital lobe is carried back, so as to cover the little brain, which 
 
v.] COMPARISON OF STRUCTURE AND FUNCTIONS. 153 
 
 is here quite underneath the brain proper. In organisation, 
 however, the occipital lobe of the monkey is of the simplest 
 order, and vastly inferior to what is found in the human brain. 
 So far as appears in the outward life of the monkey and of man, 
 there is nothing to disturb our confidence in the results of 
 electric stimulation. The monkey can use an arm as neither 
 cat, dog, nor horse can do. It can use fingers and thumbs as 
 they cannot. In these things the monkey is like to man ; the 
 other animals have no such likeness. But, apart from other 
 functions, man can use arms, hands, and eyes as the monkey 
 cannot, and brain structure differs accordingly. 
 
 What diversity there may be as to sensibility is a matter 
 more difficult of decision. Observation renders less help in 
 this branch of inquiry. But such forms of sensibility as are 
 connected with muscular action, and use of the special senses, 
 may be said to be common in the two cases. In the monkey, 
 as in man, less prominence is given to the organ of smell than 
 in other orders of life. The phases of sensibility dependent 
 on "voluntary" or "volitional" use of the organs of special 
 sense are matters of personal experience in our own case. They 
 are subjects of observation in the case of the monkey to a very 
 limited extent indeed. The animal is arrested by external 
 objects very much as other animals are. It does, indeed, 
 manifest a considerable degree of what we may call " curiosity " 
 as to objects attracting its notice. The imitative tendency it 
 shows adds considerably to the impression which such curiosity 
 is apt to make on an observer. If, however, we keep in view 
 the greater reliance the dog places on smell, and notice how 
 persistently the dog tries everything by smell, it becomes 
 difficult to say that the monkey has more "curiosity" than 
 the dog. Allowing for the diversity of organ used, there is 
 fully as much curiosity in the one animal as in the other. 
 There is a combined use of teeth and fingers possible with the 
 monkey which is not possible with the dog, and thus far the 
 former has advantages over the latter in respect to the appli- 
 ances at command. But, even with these advantages, the 
 intelligence of the one cannot be represented as equal to that 
 of the other. Tested by the possibilities of training, the in- 
 telligence of the dog is proved, I think, to be decidedly 
 
'54 
 
 THE RELA TIONS OF MIND AND BRAIN. 
 
 [CHAP. 
 
 superior. The monkey is in every way less under command 
 of man for training than the dog, and less fitted for com- 
 panionship. It is more imitative, and on that account less 
 useful, for feeble imitation is of small account as an aid to man. 
 It is less ready in appreciation of instruction, and less prompt 
 in obedience to orders when recognised. Both these facts 
 indicate a case less hopeful for training. 
 
 In making the transition to the higher orders of the monkey 
 tribe, commonly spoken of as the man-like (Anthropoid) Apes, 
 including Gorilla, Chimpanzee, and Orang, we have a still 
 closer approximation to the bodily form of man, and a nearer 
 resemblance in the structure of the brain. For illustration of 
 
 ^l 
 
 Fio. 37.— UPPER VIEW OF LEFT HEMISPHERE, AND INTERNAL ARRANGEMENT 
 
 OF RIGHT HEMISPHERE OF THE BRAIN OF THE CHIMPANZEE. 
 
 (Enlarged on a scale to equal the drawing of man's brain as shown in the following figure.) 
 
 {From. Professor Huxley's Man's Place in Nature.) 
 
 the comparative likeness of the two brains, I have been 
 favoured with the figures prepared for Professor Huxley, and 
 published in his work on Man's Place in Mature. The figures 
 have been drawn on a smaller scale than those already given, 
 but this will occasion no difficulty in studying the compara- 
 
v.] COMPARISON OF STRUCTURE AND FUNCTIONS. 155 
 
 tive form, external configuration, and internal arrangement of 
 the organs. 
 
 The figure (37) is from a photograph of the brain of a Chim- 
 panzee, which was dissected for Professor Huxley by Mr. 
 Flower, conservator of the museum of the Eoyal College of 
 Surgeons, London. The parts specially indicated are these,— 
 a, the posterior (occipital) lobe ; b, the lateral ventricle ; c, the 
 posterior cornu; and x, the hippocampus minor. The same 
 points are indicated in like manner in the figure of the human 
 brain, given as the companion to this. 
 
 These two figures are " drawings of the cerebral hemispheres of 
 a Man and of a Chimpanzee of the same length, in order to show 
 
 Front. 
 
 Via. 38.— UPPER VIEW OP THE LEFT HEMISPHERE, AND INTERNAL ARRANGE- 
 MENT OP RIGHT HEMISPHERE OP THE BRAIN OP MAN. 
 (From Professor Huxley's Man's Place in Nature.) 
 
 the relative proportions of the parts." 1 With the advantages 
 of similarity of scale, there are some disadvantages from com- 
 parative enlargement of the brain of the lower order. It must 
 be kept in view that the brain of the Chimpanzee is never more 
 1 Man's Place in Nature, p. 101. 
 
156 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 than one-half the size of the human brain, and is generally less 
 than half. Comparing these figures, it becomes plain that the 
 brain of the Chimpanzee is formed exactly on the model of the 
 human brain. The advance from the monkey to the Anthropoid 
 Ape is very marked. The frontal and posterior regions, so de- 
 fective in the monkey, are considerably more elaborate in the 
 Chimpanzee, and the smooth symmetrical surface of the convo- 
 lutions has given place to a series of convolutions beautifully 
 folded in numerous windings, closely analogous to the appear- 
 ance presented in the human brain. If, as is aptly said by Pro- 
 fessor Huxley, " the surface of the brain of a monkey exhibits 
 a sort of skeleton map of man's," 1 this brain of the Chimpanzee 
 shows the map greatly filled in, giving a rough sketch of the 
 general features of the human brain. The resemblance is very 
 close. This fact must be distinctly noted as one certain to have 
 an important significance in any argument founded on brain 
 structure in the various orders of animals. It is disputed 
 whether the Chimpanzee or the Orang is the highest in the class 
 of anthropoid apes. Cuvier placed the Orang highest ; but the 
 opposite view has been largely adopted. There is difficulty in 
 deciding, on account of the diversity of age in the specimens 
 obtained. For the purposes of the present inquiry, however, it 
 is of minor consequence whether the Orang or the Chimpanzee 
 be selected as the example with which to institute comparisons. 
 Examination of the skulls in the Edinburgh University Anato- 
 mical Museum shows a marked contrast between the three 
 orders. The skull of the Gorilla is more elongated and flattened 
 in form than the other two. The skull of the Chimpanzee is 
 more elevated and round. That of the Orang is decidedly the 
 highest and most rounded of the three. 2 The shape of the 
 skull of the Gorilla favours the conclusion that it is inferior to 
 the Chimpanzee and Orang. 
 
 "With the resemblance of brain in anthropoid apes and in 
 man must be connected a certain resemblance in bodily con- 
 
 1 Maria Place in Nature, p. 100. 
 
 2 This is illustrated by the figures of skeletons in the Museum of the Royal 
 College of Surgeons, London, which are given as the frontispiece to Pro- 
 fessor Huxley's Man's Place in Nature; by the figures on p. 79 of the same 
 work ; and by the plates in Du Chaillu's Explorations, p. 373. 
 
v.] COMPARISON OF STRUCTURE AND FUNCTIONS. 157 
 
 figuration. The two things are intimately related. A body- 
 adapted for the erect movement natural to man must be 
 analogous in structure; and where there is some degree of 
 similarity of body, it follows that there will be a similarity of 
 brain structure. These two things are so plainly illustrated 
 by comparison of the anthropoid apes with man, that there 
 can be no risk of overlooking the facts, and there can be no 
 dispute about them. The general truth here is as plain as 
 any fact in Natural History. Analogy of bodily form gives 
 analogy of brain structure. This is the most obvious con- 
 sideration suggested by simple comparison of the nerve centres 
 in man and in the apes. In physical conformation there 
 is, beside difference of skull, one essential point of contrast 
 between the ape and man. This appears in the formation of 
 the hind feet of the ape. The hind foot is in structure a foot, 
 but in function a hand. It has a thumb, opposable to the toes 
 of the foot, and in this way the ape obtains a firmness of grasp 
 with its foot which is simply impossible for man. This forma- 
 tion is adapted to the animal's life among the trees of the 
 tropical forest, its habits of movement, and modes of gathering, 
 food. Those orders most given to climbing, such as the Chim- 
 panzee, have considerably longer fingers than those less addicted 
 to climbing, such as the Gorilla ; but all alike have thumbs 
 on their hind feet, and are practically four-handed, hence 
 called quadrumana, notwithstanding a manifest difference be- 
 tween the front extremities and the hind, in accordance with 
 the different use to which the two are put. These hind 
 feet, or "the lower hands, as they may properly be called," 1 
 are adapted for a mode of life altogether different from that of 
 the great majority of the lower orders of animals. The figure 
 which is the frontispiece of the work of M. Paul B. Du Chaillu, 
 Explorations and Adventures in Equatorial Africa, shows a 
 powerfully formed hand on each of the lower limbs. The 
 distinct feature of this member is completely different from 
 the foot of man, and has so impressed the imagination 
 of the natives of Equatorial Africa as to induce amongst 
 them the belief that with these "lower hands" the ape 
 draws its victims up into the tree on which it is perched. 
 1 Du Chaillu, Explorations and Adventures in Equatorial Africa, p. 62. 
 
I S 8 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 The habits of the animal give no warrant for such a fancy, 
 but the existence of such a belief shows how these " hands " 
 on the hind limbs have affected the imagination of native 
 observers. 
 
 The anthropoid apes move on all-fours when fleeing from 
 danger, but commonly stand in the erect posture when they 
 prepare for attack. They differ somewhat in their ordinary 
 habits of movement. According to Du Chaillu, the Gorilla 
 keeps chiefly on the ground, pulling down the branches in 
 search of berries and nuts, and letting the branches go when 
 supplies are exhausted. 1 He says the common walk of the 
 animal is on all-fours, 2 and when moving in this fashion the 
 tracks show traces only of the heels and knuckles. 3 When the 
 male advances for attack, he rises to the erect posture; his 
 walk is a waddle from side to side ; 4 he advances slowly and 
 with a terrific roar ; he delivers a fearful blow with his arm, 
 keeping the hand open to give full effect to the claws, and he 
 leaves his victim in anguish just where he falls. 6 The Chim- 
 panzee, a native of the forests of West Africa, lives more 
 uniformly among the trees, and shows great agility, having 
 the aid of long fingers suited for clutching the branches. It 
 also walks on all-fours, resting on the knuckles of the fore 
 limbs and heels of the hind limbs, but it promptly stands erect, 
 and moves readily in that attitude. 6 The Gibbon is another 
 variety, long-armed, and distinguished for agility. The Orang, 
 a native of the forests of Borneo and Sumatra, delights in the 
 profuse growth of the swampy districts. According to Mr. 
 Wallace, "he walks deliberately along the branches, in the 
 semi-erect attitude which the great length of his arms and the 
 shortness of his legs give him. ... He seizes the smaller 
 twigs, pulls them towards him, grasps them together with those 
 of the tree he is on, and thus, forming a kind of bridge, swings 
 himself onward, and seizing hold of a thick branch with his 
 long arms, is in an instant walking along to the opposite side 
 
 1 A Journey to Ashango Land, p. 40. 
 
 2 Explorations and Adventures in Equatorial Africa, p. 352. 
 
 3 A Journey to Ashango Land, p. 40. 
 
 4 Explorations, p. 351. 5 j ., 29s 
 lb. p. 349. Button's Nat. Hist. 
 
v.] COMPARISON OF STRUCTURE AND FUNCTIONS. 159 
 
 of the tree." 1 All these accounts agree in referring to the 
 hind foot as distinguished by power in grasping, suited to the 
 requirements of a life spent in the dense forests of a tropical 
 region. 
 
 One other feature of these animals calls for remark ; that is, 
 the powerful canine teeth. These are the more deserving 
 notice, that the animals are not carnivorous, but live for the 
 most part on berries, nuts, and various leaves. Du Chaillu says 
 of the Gorilla, the fiercest of the three, that the animal is " a 
 strict vegetarian." 2 On this account Du Chaillu felt con- 
 siderable difficulty as to its teeth, until, he says, I discovered 
 " several trees, each of which was from four to six inches in 
 diameter, had been broken down by these animals; and I 
 found that they had bit into the heart of these trees and eaten 
 out the pith." 8 
 
 Having now the leading characteristics of these animals 
 before us, as well as the common features of their mode of 
 life, I proceed to compare the brain of the anthropoid ape with 
 the human brain. I take first the frontal lobe. This, in the 
 brain of the Chimpanzee, is considerably developed in form. 
 In comparison, however, with the same lobe in the human 
 brain, it is wanting in depth, and still has something of the 
 pointed shape found in the monkey's brain. This is quite 
 apparent in the examples preserved in the Anatomical Museum 
 of Edinburgh University.* In the brain of the Orang the 
 frontal lobe is more rounded. 5 In both these, as well as in 
 the example above (fig. 37), the gyri or folds are quite marked, 
 though not equal to those of the human brain. The posterior 
 or occipital lobe is more full and rounded, and is more closely 
 analogous in complexity of arrangement, though also deficient 
 in development downwards. It is thus, as Marshall states, 
 a brain " somewhat pointed behind, and considerably so in 
 
 1 A. R. Wallace " On the Habits of the Orang- Utan," Annals of Nat. Hist, 
 1856, vol. xviii. p. 27. 
 a Explorations and Adventures in Equatorial Africa, p. 348. 
 
 3 lb. p. 290. 
 
 4 For illustration, see plate to illustrate paper of Mr. Marshall, " On the 
 Brain of a Young Chimpanzee,'' Natural History Review, July 1861. 
 
 6 See plates illustrative of Professor Rollestou's article " On the Affinities 
 of the Brain of the Orang-Outang," Nat. Hist. Rev., April 1861. 
 
160 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 front." 1 Viewing the brain as a whole, and allowing for the 
 smaller size, we may say that no brain could come closer to 
 the human in external structure, without making it difficult 
 to distinguish between the two, or to say with certainty 
 that the examples presented are not varieties of the same 
 order. 
 
 We are still without investigations into the minute internal 
 structure of the brain of the ape, such as would enable us to 
 compare the several layers of grey matter with those of the 
 human brain. Meynert, in distinguishing between the five- 
 laminated tissue and the eight-laminated, has found that the 
 occipital lobes of the monkey contain more of the eight-lamin- 
 ated tissue than is found in the same lobes of the human 
 brain ; 2 but the facts as yet within reach are not sufficient to 
 guide us to a conclusion. In structure and relation of the 
 basal ganglia the brain of the ape is clearly analogous with 
 that of the human brain. The connecting band of the hemi- 
 spheres (corpus calloswm) is similar in appearance, though 
 " both shorter and thinner in proportion than in man," as 
 Marshall states. 3 The arrangement of ventricles and basal 
 ganglia is similar, as will be anticipated after the illustration 
 given of the similarity of interior structure in the case of the 
 dog. The size of the nerves is very decidedly larger than in 
 man. 
 
 There is thus in the brain of the ape, obviously inferior 
 though it be, an exceedingly near approximation to the brain 
 of man. The ape's brain is less in size by about a half. There 
 is still greater disparity in weight. As previously stated, we 
 have an account of two (Chimpanzee) weighing respectively 
 9§oz. and 13 J (Owen's); another of the same order, 15oz. 
 (Marshall's) ; a young Orang, 1 2 oz. (Rolleston's). In contrast, 
 the ordinary weight of brain belonging to a child of about four 
 years is from 38 to 40 oz., while the average brain of an adult 
 is from 46 to 52 oz. No doubt the most of the examples we 
 have of the ape's brain are those of young animals, in consi- 
 
 1 Nat. Hist. Review, 18G1, p. 301. 
 
 2 Dr. Dodds " On Localisation," Journal of Anatomy and Physiology, 
 vol. xii. p. 654. 
 
 3 Nat. Hist. Rev., 1861, p. 311. 
 
v.] COMPARISON OF STRUCTURE AND FUNCTIONS. 161 
 
 deration of which fact, some addition may require to be made. 
 Yet Du Chaillu says, "the actual increase in brain, in the 
 adult Gorilla (or other anthropoid apes) over the young, is very 
 slight." 1 Bischoff estimates the average at about \h\ oz. 
 In view of these statements we cannot under-estimate if we 
 allow 20 oz. as a maximum. On the other hand, as just 
 remarked, the size of the nerves is larger, and this may point 
 to a much firmer control of the great muscles of the body, with 
 much less minuteness of control over distinct parts. The most 
 prominent and important distinctions in the outward structure 
 of the organ are thus enumerated by Professor Huxley. In the 
 anthropoid apes (1.) "the brain is smaller, as compared with 
 the nerves which proceed from it, than in man ; (2.) the cere- 
 brum is smaller relatively to the cerebellum ; (3.) the sulci and 
 gyri are generally less complex, and those of the two cerebral 
 hemispheres are more symmetrical; (4.) the hemispheres are 
 more rounded and deeper in man than in the anthropoid apes, 
 and the proportions of the lobes to one another are different. 
 Furthermore, certain minor gyri and fissures, present in the 
 one, are absent or rudimentary in the other." 2 When all these 
 differences are taken into account, we recognise the brain of the 
 ape as a smaller and simpler brain constructed on the model of 
 the human brain. 
 
 I shall first compare the normal brain of the ape with the 
 human brain, when arrested in its growth. The ape with a 
 brain modelled like man's, and weighing 15 to 20 oz., shows 
 himself active, powerful, and able to assail any adversary : man 
 with a brain better developed, and 10 to 15 oz. heavier, is totter- 
 ing, feeble, and idiotic, unable to defend himself from even a 
 weak assailant. If configuration and structure of brain afford 
 a measure of intelligence, our poor idiotic fellow-man should be 
 so much clearer in intellect, and decided in action, than the 
 highest specimen of apes. But it is not so. There are many 
 examples in human history of the brain being well formed, but 
 arrested in process of unfolding. There is in the Anatomical 
 Museum of Edinburgh University (No. 1969), presented by the 
 
 1 Explorations, p. 375. 
 
 2 "On the Zoological Relations of Man with the Lower Animals." — Nat. 
 Hist. Review, 1861, p. 79. 
 
 L 
 
1 62 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 late Professor Henderson, the brain of an idiot girl, who was not 
 more than eight years of age, which is beautifully formed, but so 
 arrested in growth as to be only a little larger than the ape's 
 brain. The smaller brain of the ape is compatible with maturity 
 of ape life ; the larger brain was incompatible with the ordinary 
 functional activity of early human life. There is in the same 
 collection another example, which is the brain of a male imbecile 
 who had a long life, and which shows a development of the 
 several lobes quite beyond the aspect of the ape's brain, yet 
 he was, as is said, " weak in both body and mind." Whatever 
 be the advance in function attendant on advance in compara- 
 tive development of the brain proper, it is clear that restraint 
 in growth of the human brain does not bring man to a condi- 
 tion analogous to that of the ape. Between the two cases 
 there is such difference, that comparative development does not 
 appear to be the test of comparative power muscular or 
 " mental." And this difference is so marked, that even though 
 the brain of man be both in size and complexity of structure 
 much beyond that of the most powerful of the Anthropoid Apes, 
 there is in human life the weakness and distress of an abnormal 
 condition. 
 
 In accordance with this view, Gratiolet, while referring to the 
 fact that the arrangement of cerebral folds is the same in the 
 brain of the ape as in that of man, says, " The study of the brain 
 of microcephalic (small-brained) persons has provided me with 
 other elements, by the aid of which the absolute distinction of 
 man is evidently and anatomically proved." He then states 
 that "the temporo-sphenoidal convolutions (lower middle) appear 
 first in the brain of monkeys, and are completed by the frontal 
 lobe ; while precisely the inverse order takes place in man, the 
 frontal convolutions appearing first, the temporo-sphenoidal 
 showing themselves last. . . . From this fact, rigorously 
 verified, a necessary consequence follows ; no arrest in the 
 progress of growth could possibly render the human brain 
 more similar to that of monkeys than it is at the adult age ; 
 far from that, it would differ the more, the less it were de- 
 veloped." 1 
 
 1 Transactions de la SocitStb d' Anthropologic, Paris — quoted by Du Chaillu, 
 Explorations, p. 377. 
 
v.] COMPARISON OF STRUCTURE AND FUNCTIONS. 163 
 
 I pass from this to a comparison of the brain of the ape with 
 the normal human brain, in order to take account both of the 
 differences and the similarities. And first, as to the differences. 
 The normal human brain is considerably more than twice as 
 heavy as the maximum weight of the ape's brain. An ordinary 
 human brain is three times heavier than many of the apes' 
 brains which have come under observation. The average 
 weight of a human brain in males of the Australian races has 
 been stated at 42-8 oz. ; of the African races, 45-6 oz. ; of the 
 Oceanic races at 46 - 5 oz. ; and of the European at between 49 
 and 50 oz., while some examples of the European brain have 
 risen above 60 oz. 1 While making this contrast, it must be 
 kept in view that the full-grown ape is nearly the equal of man 
 in stature. A young gorilla shot by Du Chaillu measured 5 
 feet 8 inches; 2 another male, 5 feet 6 inches; 8 another, 5 feet 
 9 inches ; 4 a female, which is always considerably smaller, 
 4 feet 7 inches ; s another, 4 feet 4 inches. 6 These facts indi- 
 cate that the brain is a more important organ in human life 
 than in the life of the ape. The superiority in man's case 
 appears still more in the fulness of form and complexity of 
 arrangement in the human brain. The heavier brain is also 
 more elaborately organised. With a stature nearly similar, 
 with muscular development favouring the ape, with configu- 
 ration of body very analogous, there is nevertheless the clearest 
 evidence from comparison of mere mass and weight of the 
 brain proper, that this organ performs a much more important 
 part in human life than in the life of the ape. And this 
 becomes still more marked when it is added that the cere- 
 bellum or little brain is proportionately larger in relation to 
 the brain proper in the ape than in man. Investigations as to 
 the functions of the cerebellum, applying to a great variety of 
 animals, and carried even to the extent of its entire removal, 
 while the animal continued to live, have shown that the cere- 
 bellum is not closely connected with the general government 
 of animal life, but more expressly with co-ordination of move- 
 ments involving both sides of the body. Ferrier states the 
 result of detailed experiments in the following terms: "The 
 
 1 P. 23 infra. 3 Explorations, p. 2°76. 6 lb. p. 256. 
 
 2 Explorations, p. 435. * lb. p. 304. ° lb. p. 261. 
 
164 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 cerebellum would, therefore, seem to be a complex arrange 
 ment of individually differentiated centres, which in associated 
 action regulate the various muscular adjustments necessary to 
 maiotain the equilibrium of the body." 1 There is a large 
 amount of evidence in confirmation of this position. If then 
 this conclusion be adopted, it will follow that there is relatively 
 much larger provision in the brain of the ape for maintaining 
 equilibrium as it moves among the trees of the forest than 
 there is in the case of man, who moves more uniformly on 
 an even surface, though his activity takes a much more varied 
 form. The greater proportion of the cerebellum to the cere- 
 brum indicates adaptation to the mode of life of the animal 
 by the difference in the balance of parts included in the 
 encephalon. 
 
 On the other hand, it is needful to dwell on the similarity of 
 structure of the brain proper in man and in the ape. There is 
 certainly much of great importance for the present investi- 
 gation connected with this resemblance. The analogy is so 
 close, that if we lay aside these three points, the order in which 
 the lobes appear, the comparative bulk and weight of the 
 cerebrum, and the relative size in proportion to the cerebellum, 
 there is a very exact resemblance. Tbis resemblance appears 
 in the form of the hemispheres, in the relations of the lobes, 
 and in the distribution of convolutions within each lobe. No- 
 where in the whole animal creation is there a brain at all 
 approaching that of the anthropoid ape in respect of its 
 structural resemblance to the human cerebrum. This is one 
 of the most conspicuous and important facts in the whole line 
 of the present department of the subject. It is accordingly to 
 be regarded as a crucial fact for the theory of brain function. 
 For a proper estimate of its significance, it is needful to look 
 at the fact as it stands connected with the bodily structure of 
 the ape, and as it is related to what is known of its intelli- 
 gence. 
 
 The ape is as like to man in physical structure as its brain 
 is like to the brain of man. A harmony of brain and body in 
 each case is an essential feature in the comparison. The differ- 
 ences in bodily conformation have been already mentioned, and 
 1 Functions, p. 109. 
 
v.] COMPARISON OF STRUCTURE AND FUNCTIONS. 165 
 
 need not be repeated. The close resemblance in form and 
 build is very striking, and is amply proved by the likeness of 
 the skeleton in the two cases. Accordingly the muscular system 
 of the ape differs greatly from that of animals more familiar to 
 us, and proportionately it resembles that of man. In harmony 
 with this difference of muscular arrangement, and in adaptation 
 to an erect posture, there is a difference in the outward formation 
 of the nerve centre, fitting it for the requirements of rapid 
 movement in the upright attitude. It is in this adaptation of 
 form to requirements involved in the bodily form that the 
 brain of the ape possesses its close resemblance to the brain of 
 man. In adaptation to muscular action, a great part of the 
 explanation is found of the similarity of brain structure. 
 Evidence seems to favour the conclusion that the larger part 
 of the resemblance is thus explained. Difference of muscular 
 action there is in the two cases, since the ape uses its hands 
 for feet, walking on the knuckles ; and uses its feet for hands, 
 gaining largely in security of movement by grasping objects 
 with the foot. 1 But movement in the erect posture, while the 
 fore limbs are used as arms, involves an essential difference in 
 muscular system from what is common in other animals. For 
 this muscular diversity the form of brain found in the ape is 
 the natural equivalent. 
 
 The aipe is far less like to man in "intelligence" than its train 
 is like to the human train. Beginning with the physical adapta- 
 tion of the ape for the acquisition of knowledge, there is far less 
 fitness for acquiring knowledge than there is for active effort to 
 obtain the means of subsistence, or to escape from danger. 
 There is no such sensitiveness in the ape's hand as there is in 
 the hand of man, and no indication in the ape of the power to 
 use the sense of touch as it is employed by man for acquiring 
 knowledge of things around. Thus speaking of the Gorilla, Du 
 Chaillu says, "the arms have prodigious muscular develop- 
 ment," but "the palm of the hands is naked, callous, and 
 intensely black." 2 The hand which, while it is bare in the 
 palm, is nevertheless " callous," is not the hand of a being 
 capable of " intellectual " development by use of the general 
 
 1 See Figures 9 and 10 in Huxley's Man's Place in Nature, pp. 32, 47. 
 
 2 Explorations, p. 357. 
 
166 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 sense of touch, though that is the lowest type of the instruments 
 of knowledge possessed by man. If regard be paid to the 
 results of electric stimulation of the brain, strong confirmatory 
 evidence is obtained. It will be remembered that all the 
 centres of stimulation in the brain of the Monkey are gathered 
 on the central portion where the mass is deepest. In this region 
 also the greatest depth is found in the brain of the Man-like Ape. 
 Next, it will be recalled that the larger portion of the central 
 area is covered by centres concerned in the movement of the 
 limbs. Apart from this central region, it is to be noticed that 
 the ape's brain, when compared with the brain of man, is 
 deficient in both the front and posterior lobes. From these 
 things affecting the structure of the brain, it follows that the 
 ape is greatly less fitted in comparison for the use of the 
 physical appliances suited for the acquisition of knowledge. 
 So far as these considerations carry us, the ape does not rank 
 high intellectually. It is, however, acute in hearing, and 
 readily alarmed by the slightest sound ; its acuteness in this 
 respect tending to drive it away from the approaching object, 
 rather than to attract it towards what is novel. On the other 
 hand, its power of vision is less than that of hearing. 
 
 From this line of evidence, I turn to the statements made 
 concerning the habits of the ape. Of all the species mentioned, 
 the Gorilla is the most fierce and dangerous. The others are 
 less inclined for attack, but even the Gorilla makes his assault 
 only when pressed by the hunter. All three species named 
 above have been under observation to a considerable extent. 
 I shall first consider the habits of the animals in their natural 
 state, and afterwards the results of training. 
 
 All three species have their natural resort in the dense forest, 
 and their physical conformation fits them for life among the 
 trees. The Chimpanzee and Orang dwell most commonly up 
 the trees ; the Gorilla prefers the level ground, and only the 
 females and young mount the trees for protection. All three 
 feed upon fruit and other vegetable productions; none of 
 them is carnivorous. All possess strong canine teeth, but 
 neither the Gorilla nor the Orang uses these in attack ; Dr. 
 Savage says that the Chimpanzee does. They are not liable to 
 attack from other animals, but live a quiet easy life in search 
 
v.] COMPARISON OF STRUCTURE AND FUNCTIONS. 167 
 
 of food among the trees of the forest. Mr. Wallace states that, 
 according to the testimony of the natives of Borneo, the Orang 
 or Mias is attacked by no animal save by the crocodile, when 
 the fruit-eater has descended to the banks of the river in search 
 of supplies. At such a time the crocodile has been seen to 
 venture an assault. When this happens, the Orang " gets on 
 the reptile's back, beats it with its hands and feet on the head 
 and neck, and pulls open its jaws till it rips up the throat." 1 
 This description harmonises with the account given by Du 
 Chaillu of the manner in which the Gorilla delivers his assault 
 with his brawny arm. All three animals are fierce when roused, 
 though the male Gorilla is much the fiercest, being the one 
 most alarmed and enraged by approach of man. The Orangs 
 "seem not much alarmed at man," 2 on whom they look down 
 with comparative coolness. Dr. Savage tells "that when 
 wounded they have been known to stop the flow of blood by 
 pressing with the hand upon the part, and, when this did not 
 succeed, to apply leaves and grass." All these animals wander 
 from place to place. They never select and retain a favourite 
 place of abode. The male Gorilla commonly sleeps at the foot 
 of a tree, with his back against the trunk, while the female and 
 the young one are in the branches above. The Chimpanzee 
 and Orang sleep up the tree. The Orang makes a nest for 
 itself by breaking off branches and laying them across each 
 other. This appears to be the highest exercise of "intelli- 
 gence " recorded of it ; and the value of this fact is somewhat 
 enhanced by the statement made by Mr. Wallace : " As soon as 
 he feels himself badly wounded, he makes a nest, which, if he 
 completes, is so secure that he will never fall from it." 8 Some 
 have described these resting-places as huts. Dr. Savage says, 
 "Their construction is more that of nests than Mis, as they 
 have been erroneously termed by some naturalists." Such 
 nests afford no shelter, and are occupied only at night. 4 The 
 female is gentle and kind to her young one, which clings so 
 closely to the mother's bosom that hunters often fail to notice 
 the presence of the little one, until the two fall together to the 
 ground. 
 
 1 Annals of Wat. Hist, second series, vol. xviii. p. 29. 2 lb. p. 28. 
 
 3 /j, p. 27. 4 Huxley's Man's Place, p. 44. 
 
168 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 Andrew Battell states that when travellers in the woods have 
 left their fires burning, the apes " will come and sit about the 
 fire till it goeth out, for they have no understanding to lay the 
 wood together." 1 "TheOrangis sluggish. . . . Hunger alone 
 seems to stir Mm to exertion, and, when it is stilled, he re- 
 lapses into repose. When the animal sits, it curves its back 
 and bows its head, so as to look straight down to the ground ; 
 sometimes it holds on with its hands by a higher branch, some- 
 times lets tbem hang down phlegmatically by its side; and in 
 these positions the Orang will remain, for hours together, id 
 the same spot, almost without stirring." 2 
 
 In this narrative I have embraced everything in the natural 
 habits of the ape which appears to throw any light on its mode 
 of life, and specially on its "intelligence." As the result of 
 such a summary of the testimony of skilled witnesses, it is 
 clear that no high degree of intelligence can be attributed to - 
 these animals in their natural state. Theirs is a quiet easy 
 life, spent in wandering from tree to tree, eating all the fruit 
 which comes within their reach, and going to sleep when 
 night falls. The nest-building is the highest proof of intellect 
 they give ; and in view of what is done in this way by the 
 smaller birds, the fact affords no claim to a high intellectual 
 rank. 
 
 When, however, we pass to observations bearing on the 
 conduct of the ape when placed under the influence of man, 
 the case is somewhat improved. Our comparison here is 
 reduced to two of the three apes specially referred to above, 
 for Du Chaillu declares the Gorilla untamable. A young one 
 taken by him, reckoned not more than three years of age, and 
 only two feet six inches in height, proved so powerful that it 
 required four men to master him. When any one approached 
 his cage, he instantly made a rush at the intruder. He 
 would eat nothing but the fruit which was his usual fare, 
 and he showed no disposition to friendliness even with those 
 who fed him. 8 Mr. Ford's testimony is similar. 4 The 
 Chimpanzee and Orang manifest different temper. They too 
 may be fierce when attacked, but they are naturally more 
 
 1 Huxley's Man's Place, p. 4. 3 MxplorcUions, p. 207. 
 
 2 lb. p. 34. * Huxley's Man's Place, p. 52. 
 
v.] COMPARISON OF STRUCTURE AND FUNCTIONS. 169 
 
 gentle, and become readily familiarised with the presence of 
 man when kindness is shown them. Mr. "Wallace secured a 
 young Orang, or Mias, which was quite a baby, its age being 
 reckoned at only about a month. It was " quiet and con- 
 tented." It showed all the characteristics of slow progress 
 towards maturity, with which we are familiar in the human 
 infant. In this respect the Orang was a contrast to a young 
 monkey, which had just got his first teeth, and was placed along 
 with the other. While the Orang was " lying helpless," the 
 young monkey was " examining everything with its fingers, 
 and seizing hold of the smallest objects with the greatest pre- 
 cision." Thus the animal inferior in organisation more quickly 
 reached maturity, in harmony with facts in the life of still 
 lower orders. Bodily development with the Orang is more in 
 harmony with the slow stages of progress in the early period 
 of human life, with this exception, however, that the Orang 
 has a muscular power quite unknown to man. Consequent 
 upon this, there appeared in Mr. Wallace's young specimen a 
 proneness to muscular action in certain forms, much beyond 
 anything usual* with a child. It was " contented when it had 
 a bit of rag or stick to grasp." This manifestation of grasping 
 power, and consequent restfulness when exercised, is in har- 
 mony with all the habits of the early life of the animal ; for, 
 as we have seen, the young ape clings to its mother's body, 
 grasping by the hair or skin. Mr. Wallace's specimen was 
 trained to cling to a ladder, and when it fell from that, " it 
 never seemed hurt by any of its tumbles." It began to " learn 
 to run alone," and " would scream violently when not attended 
 to." The want of sensibility must be noted here, as well as 
 the irritability under neglect. The sensitive part of the body 
 in the ape seems to be the under lip, which is pushed out till 
 it is very prominent. Between the early life of man and the 
 ape there is thus close analogy in respect of slow rate of pro- 
 gress ; but there is complete contrast in muscular development, 
 and consequent experience. This contrast points to a diverg- 
 ence of life in the two cases, and to a special and very 
 restricted exercise of brain power in the case of the ape, 
 contrasting decidedly with the ordinary conditions of brain 
 action in human life. 
 
170 THE RELATIONS OF MIND AND BRAIN. [CHAP. 
 
 There is in the ape a certain degree of the imitative tend- 
 ency, which, however, appears much more fully in the smaller 
 monkeys, and the smallest but most agile long-armed apes, such 
 as the Gibbon. Mr. Wallace's young Orang "would cross his 
 arms like a little Napoleon." Many narratives are given of apes 
 being trained to use knife and fork, and to shake hands, while 
 tricks of an imitative sort, thieving and artful concealment, are 
 all attributed to them. The earliest accounts of them, dating 
 from the close of the sixteenth century, speak of them " imitat- 
 ing human gestures." 1 The strongest testimony on this sub- 
 ject which has come under my notice is that given by Buffon 
 concerning a tame Chimpanzee, named by him an Orang. 
 Professor Huxley, remarking on the fact that Buffon was 
 more fortunate than Linnaeus in his opportunity for gaining 
 acquaintance with apes, says of the former, " Not only had he 
 the rare opportunity of examining a young Chimpanzee in the 
 living state, but he became possessed of an adult Asiatic man- 
 like ape, the first and the last adult specimen of any of these 
 animals brought to Europe for many years." 2 Buffon may, 
 therefore, be taken as one of the best authorities as to the 
 ape's powers under training. Speaking of the animal under 
 his own observation, he says : " Its air was melancholy, its 
 deportment grave, its movements measured, its disposition 
 gentle, and very different from that of other monkeys. It had 
 none of the impatience of the Magot (Barbary ape), the ferocity 
 of the baboon, or the extravagance of the monkeys. It may 
 be said that it had been well taught ; but the others had also 
 received their education. A sign or a word was sufficient for 
 our Orang-outan, whilst the baboon required the stick, and the 
 others the whip, as they only obeyed under the fear of chastise- 
 ment. I have seen this animal present its hand to lead out 
 visitors, or walk about with them gravely as if it belonged to 
 the company. I have seen it seat itself at table, unfold its 
 napkin and wipe its lips, use its spoon and fork to carry its 
 food to its mouth, pour its drink into a glass, and touch glasses 
 when invited ; fetch a cup and saucer to the table, put in sugar, 
 pour out its tea and leave it to cool before drinking it ; and all 
 this without any other instigation than the signs and words of 
 1 Huxley's Marin Place, p. 2. z lb. p. 13. 
 
v.] COMPARISON OF STRUCTURE AND FUNCTIONS. 171 
 
 its master, and often of its own accord." 1 This is a striking 
 account of imitative power, and coming from such an observer 
 as Buffon, merits special consideration. The opening statement 
 as to disposition does not give the impression of an animal 
 sharp in observation, or possessed of great power of self-direc- 
 tion. Melancholy, grave, gentle, and patient; these are the 
 qualities specified as prominent. Compared with the charac- 
 teristics of the monkey, they are nearly the opposite in all 
 respects, so that we might say of the larger animal, that it is 
 less tricky and more submissive than the monkey. The imi- 
 tative tendency appears strongly, for all the acts described may 
 be classed under the single head of imitated actions. Their 
 value is further diminished by the extent to which they are con- 
 nected with the animal's feeding, in which the stimulus of the 
 palate renders very efficient aid to the trainer. So much is this 
 the case, that all actions connected with the use of food must 
 be ranked on a decidedly lower level than the actions which 
 accomplish an end of such a nature as to be quite removed 
 from the influence of the animal's taste or appetite. Tried 
 by this rule, the case before us, surprising as it is, stands quite 
 on a low platform as to intelligence. The actions are remark- 
 able when regarded as those of a beast ; they are of hardly any 
 account as the actions of an intelligent being. They show 
 intellect enough to notice the use men make of certain articles 
 for conveying food to their mouths, and to imitate them in 
 such actions. But all the actions so imitated are of a nature 
 to be more readily imitated by the ape than by any other animal, 
 on account of the close resemblance of its bodily structure to 
 that of man. The use of the table-napkin is the act which 
 seems to give some gleam of higher intelligence, but it is some- 
 what explained when it is remembered that the under lip is 
 the special seat of sensibility, and on this account easily acted 
 upon. But the actions themselves make little demand on in- 
 telligence. They are such as might be done by a child six 
 years of age without occasioning remark. They are wonder- 
 ful as the actions of an animal which is higher than man in 
 
 1 Histoire Naturelle (1766), vol. xiv. p. 53. For a carefully prepared account 
 of the Apes, see Museum of Natural History, by Richardson, Dallas, Cobbold, 
 Baird, and White. 
 
172 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 strength, which has its natural life in the forest, and which 
 obtains its food by plucking fruit from the trees ; but the 
 actions are insignificant when regarded as those of an animal 
 whose brain is singularly like that of man. There is on the 
 part of the ape no indication of the aptness for training 
 which has made the horse so valuable as the servant of 
 man. With its great muscular strength the Ape might have 
 rendered powerful aid ; but this melancholy sauntering animal, 
 with largely developed muscular system, and with most of 
 the advantages of human configuration, does not show intellect 
 enough to be a fellow-worker with man. In the abode of man 
 it has lost its sphere for the exercise of its muscular energy. 
 With physical organisation suited for work which the horse 
 could not attempt, it accomplishes far less. With a brain 
 formed in much closer analogy with the human brain than that 
 of the dog, and even more obviously than the dog, " walking 
 about with men as if it belonged to the company," it does not 
 show the dog's power to appreciate man's wishes, or to fulfil 
 them by a course of self-directed effort when beyond its mas- 
 ter's sight. Greater in muscular development, and decidedly 
 nearer the elevation of humanity in the structure of the 
 brain, the ape is intellectually inferior to the dog and the 
 horse. 
 
 Accordingly, the conclusions of Buffon, after subjecting the 
 animal to careful personal observation, are quite decided. Ee- 
 ferring to the imitative acts, he says, "he imitates, but not 
 voluntarily." " He has a body, members, senses, a brain, and 
 a tongue perfectly similar to those of a man, but he performs 
 no action that is characteristic of man." " In relative qualities 
 the ape is further removed from the human race than most 
 other animals." " All the other parts of the body, head and 
 members, both external and internal, so perfectly resemble 
 those of man, that we cannot make the comparison without 
 being astonished that such a similarity in structure and 
 organisation should not produce the same effects." 1 
 
 The results of the comparison between man and the ape pre- 
 
 1 Histoire Naturette, vol. xiv. pp. 38, 30, 41, 61. Smellie's Translation of 
 Buffon's Nat. Hist., vol. x. pp. 33, 25, 35, 55. 
 
v.] COMPARISON OF STRUCTURE AMD FUNCTIONS. 173 
 
 sented in the preceding pages, give clear and ample warrant for 
 Professor Huxley's reference to " the great gulf which inter- 
 venes between the lowest man and the highest ape in intellec- 
 tual power." 1 
 
 Professor Huxley, while inclining to a more favourable view 
 of the ape's intellectual condition than I am able to take, puts 
 the contrast of action and brain structure so distinctly that I 
 prefer to quote his statements. He says : " So far as I am 
 aware, no one has attempted to dispute the accuracy of the 
 statements which I have just quoted regarding the habits of 
 the two Asiatic man-like apes (the Gibbon and Orang), and, if 
 true, they must be admitted as evidence that such an ape — 
 Istly. May readily move along the ground in the erect or semi- 
 erect position, and without direct support from its arms. 2dly. 
 That it may possess an extremely loud voice, so loud as to be 
 readily heard one or two miles. Zdly. That it may be capable 
 of great viciousness and violence when irritated ; and this is 
 specially true of adult males, ithly. That it may build a nest 
 to sleep in." 2 As to comparative brain structure in the case 
 of man and the ape, Professor Huxley says : " So far as cerebral 
 structure goes, it is clear that man differs less from the Chim- 
 panzee or the Orang than these do even from the monkeys, and 
 that the difference between the brains of the Chimpanzee and 
 of man is almost insignificant when compared with that between 
 the Chimpanzee brain and that of a lemur. It must not be 
 overlooked, however, that there is a very striking difference in 
 absolute mass and weight between the lowest human brain and 
 that of the highest ape — a difference which is all the more remark- 
 able when we recollect that a full-grown Gorilla is probably 
 pretty nearly twice as heavy as a Bosjesman, or as many an Euro- 
 pean woman. It may be doubted whether a healthy human adult 
 brain ever weighed less than thirty-one or thirty-two ounces, or 
 that the heaviest Gorilla brain has exceeded twenty ounces." 3 
 
 A comparison of these two statements, the one concerning 
 the characteristic actions of apes, and the other concerning the 
 close resemblance between their brain and that of man, will 
 show how striking is the problem before us, and how important 
 it is as bearing on the functions of the grey matter of the 
 1 Man's Place, p. 102. 2 lb. p. 42. 3 lb. p. 102. 
 
174 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 brain. The first quotation refers to the Gibbon and Orang, but 
 it equally applies to the Chimpanzee and the Gorilla ; the last 
 quotation applies to all the three highest orders, leaving out of 
 account the long-armed Gibbon, which moves more by its arms 
 than by its legs. 
 
 If now a reference be made to the two figures (pp. 154, 155), 
 the importance of the structural analogy of the two brains will 
 at once appear. Confining attention to the left hemisphere in 
 the two cases, and remembering the enlargement of the repre- 
 sentations of the Chimpanzee's brain for the purpose of com- 
 parison, it will be observed that the ape's brain is comparatively 
 somewhat broader in proportion. With this difference, both 
 are on the same model, and so like as to appear as if the ape's 
 brain were only a less developed example of the human brain. 
 
 I have now only to give a summary of the results of this 
 inquiry as to the brain of man and of the ape. The two are 
 similar in the nature and relation of the grey matter and the 
 white, noting only these two points, that we are not in posses- 
 sion of results of minute investigation as to the number and 
 size of cells in the grey matter of the ape's brain, and that the 
 nerve tracts issuing from the ape's brain are stronger than 
 those belonging to man. The two brains differ so far in weight 
 that the maximum brain of the ape is a third less than the 
 minimum weight of the normal human brain. The two brains 
 are closely analogous in structural arrangement, both superficial 
 and internal, embracing within the former the hemispheres, 
 lobes, and convolutions ; within the latter, the ventricles and 
 basal ganglia. Thus we have in the ape's brain the closest 
 possible approximation to the human brain — certainly the 
 nearest resemblance known to exist in the animal kingdom; 
 and yet the ape does not show intelligence equal to that 
 observed in the ordinary life of animals whose brains are far 
 from presenting so close analogy with the human brain. So 
 far away is this animal from the intellectual level of man, 
 that it is a " great gulf which intervenes between the lowest 
 man and the highest ape in intellectual power." 1 The brain of 
 the ape, when compared with that of man, supplies the clearest 
 proof presented anywhere by comparative anatomy and physio- 
 1 Huxley's Man's Place, p. 102. 
 
v.] 
 
 COMPARISON OF STRUCTURE AND FUNCTIONS. 
 
 175 
 
 logy, that the structure and form of the brain is no sure index 
 of intellectual power. 
 
 I close this course of inquiry as to comparative brain 
 structure, by presenting two examples of brain from the more 
 gigantic animals, the first being that of the Elephant. 
 
 In examining this example of brain it will be noticed 
 that the Sylvian fissure (S) runs almost directly up to the 
 vertex, nearly dividing the organ into halves. To the left 
 of it there appear three main convolutions, laid up iu beautiful 
 
 Front. 
 
 Fig. 39.— BRAIN OF THE ELEPHANT. 
 (After example in the Atlas of Leuret and Gratiolet.) 
 
 and complicated folds. To the right the mass is more extended, 
 and the convolutions still more complicated. The region to 
 the right of the Sylvian fissure is the frontal region, and is 
 more extended, and more varied in form than the portion of the 
 organ which lies behind. 
 
 When this brain is taken along with others, such as that of 
 
176 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 the horse and the ape, it is evident that as the brain becomes 
 large, and elaborate in convolution, it stands in close relation 
 with large muscular development. The muscular power of the 
 elephant is well known, as tested by the large weight which it 
 can draw or carry on its back. Mr. G. P. Sanderson, superin- 
 tendent of the Government Elephant-Catching Establishment 
 in Mysore, speaking of the weight which the animal may 
 carry on his back, says : " Half a ton is a good load for an 
 elephant for continuous marching. In hilly country seven 
 hundredweights is as much as he should carry. I have known 
 a large female carry a pile of thirty bags of rice, weighing 82 
 lbs. each, or one ton and two hundredweights, from one store- 
 room to another, 300 yards distant, several times in a morn- 
 ing." 1 Mr. Sanderson's long experience in catching, taming, 
 training, and superintending the work of elephants makes his 
 testimony of special value as to the habits, disposition, and 
 intelligence of the animal. 
 
 The great strength of the elephant is certainly the outstand- 
 ing characteristic which first arrests attention. In illustration 
 of this, very few can be prepared for the statement Mr. Sander- 
 son makes as to the size of the legs. After mentioning that 
 the highest elephant he had seen was 9 feet 10 inches at the 
 shoulder, adding that "there is little doubt that there is not an 
 elephant 10 feet at the shoulder in India," he says, "twice 
 round an elephant's foot is his height, within one or two 
 inches; more frequently it is exactly so." 2 He gives the 
 average circumference of a large male elephant's foot as about 
 4 feet 8 inches, the diameter being about 18 inches. As to 
 the early period at which a calf elephant is able to go with the 
 herd of wild elephants on the march, the following informa- 
 tion is given : — " When a calf is born the herd remains with 
 the mother two days; the calf is then capable of marching. 
 Even at this tender age calves are no encumbrance to the 
 herd's movements ; the youngest climb hills, and cross rivers 
 assisted by their dams. In swimming, very young calves are 
 supported by their mother's trunks, and held in front of them." 8 
 " Calves are always quick movers. I have used them as small 
 
 1 Thirteen Years among the Wild Beasts of India, p. 87. 
 
 2 lb- ?■ W». s lb. p. 51. 
 
v.] COMPARISON OF STRUCTURE AND FUNCTIONS. 177 
 
 as thirteen hands at the shoulder, with a soft pad and stirrups, 
 bestriding them as a pony. They are wonderful little creatures 
 forgetting up or down any difficult place; they give no trouble, 
 and will keep up with a man running at any pace before 
 them." 1 
 
 Though so early able to endure the fatigue of marching, 
 elephants are long in attaining maturity. " The elephant is full 
 grown, but not fully mature, at about twenty-five years of age. 
 At this period it may be compared to a human being at eighteen ; 
 and it is not in full vigour and strength till about thirty-five." 2 
 
 A conspicuous feature in the conformation of the elephant is 
 the trunk, which, as an additional limb, virtually performs the 
 functions of an arm, while the animal retains its solid foothold 
 on all four legs. The trunk is at the same time an organ by 
 which, as well as by the throat, sound is emitted. " A peculiar 
 sound is made use of by elephants to express dislike or appre- 
 hension, and at the same time to intimidate. ... It is produced 
 by rapping the end of the trunk smartly on the ground, a 
 current of air, hitherto retained, being sharply emitted through 
 the trunk, as from a valve, at the moment of impact." 3 The 
 trunk is a sensitive portion of the body, its extremity, with 
 slight prominence, being distinguished by a delicate power of 
 touch. " Whilst fording water on cold nights, tame elephants 
 curl up their trunks and tails to keep them out of it." 4 Mr. 
 Sanderson speaks of- the " attitude elephants often assume 
 when in uncertainty or perplexity, putting the trunk into the 
 mouth, and holding the tip gently between the lips." 6 When 
 the animal is attacked by the natives, spears are " thrown at 
 his trunk and head." 6 Mr. Sanderson denies that the trunk is 
 used as a weapon of offence, but affirms, in opposition to the 
 statements of Sir Emerson Tennent, that the tusks are regularly 
 so employed — "Far from tusks being useless appendages to 
 elephants, and of little service for offence, they are amongst the 
 most formidable of any weapons with which nature has furnished 
 her creatures, and none are used with more address." Mr. 
 Sanderson also contradicts the current impression that the 
 trunk is used for lifting heavy weights, and so brushes away 
 
 1 Thirteen Years among the Wild Beasts of India, p. 88. 2 lb. p. 60. 
 
 3 lb. p. 49. 4 lb. p. 51. 6 lb. p. 54. « lb. p. 60. 
 
 M 
 
178 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 by a single sweep all the fine stories in which we have taken 
 delight as to the wonderful feats of strength by '-use of the 
 trunk. He says that "small trees are overturned by push- 
 ing with the curled trunk, or feet if necessary." 1 But as 
 to the more ordinary uses of the trunk, he makes the follow- 
 ing important statement : — " Much misapprehension prevails 
 regarding the uses and power of the elephant's trunk. This 
 organ is chiefly used by the animal to'procure its food, and to 
 convey it, and water, to its mouth ; also to warn it of danger 
 by the senses of smell and touch. It is a delicate and sensi- 
 tive organ, and never used for rough work. In any dangerous 
 situation, the elephant at once secures it by curling it up. The 
 idea that he can use it for any purpose, from picking up a 
 needle to dragging a piece of ordnance from a bog, is, like 
 many others, founded entirely on imagination. An elephant 
 might manage the former feat, though I doubt it ; the latter he 
 would not attempt. Elephants engaged in such work as drag- 
 ging timber invariably take the rope between their teeth ; they 
 never attempt to pull a heavy weight with the trunk. In 
 carrying a light log they hold it in the mouth as a dog does a 
 stick, receiving some little assistance in balancing it from the 
 trunk. Tuskers generally use their tusks for this and similar 
 purposes, and are more valuable than females for work. An 
 elephant is powerful enough to extricate a cannon from a diffi- 
 cult situation, but he does it by pushing with his head or feet, 
 or in harness — never by lifting or drawing with his trunk. . . . 
 Elephants do not push with their foreheads, or the region above, 
 the eyes, but with the base of the trunk, or snout, about 1 foot 
 below the eyes." 2 When the wild elephant makes an attack, 
 "the head is held high, with the trunk curled between the 
 tusks, to be uncoiled in the moment of attack." 3 " An elephant 
 rarely uses its trunk for striking other elephants or man. 
 Newly caught ones seldom even seize any one coming within 
 their reach with their trunk ; they curl them up and rush at 
 the intruder." 4 The ordinary use of the trunk is gathering 
 food, in the shape of grass, leaves, and tender twigs. 
 
 As to the cranium and brain, Mr. Sanderson gives the fol- 
 
 1 Thirteen Tears among the Wild Beasts of India, p. 66. 
 
 2 lb. p. 82. 3 lb. p. 189. 4 lb. p. 82. 
 
v.] COMPARISON OF STRUCTURE AND FUNCTIONS. 179 
 
 lowing, information :—" Internally the cranium consists of 
 light cellular hone of very open construction. The walls 
 between the cells are as thin as note-paper. The cells differ in 
 size; the largest has a capacity of about two wine-glasses. 
 There are no powerful bones, except one knob in front; a 
 walking stick may almost be driven through an elephant's 
 skull from the sides. The only vital portion of the head is 
 the brain ; this lies low and far back. In a very large male 
 elephant, say 9£ feet at shoulder, its extreme length horizon- 
 tally is 12 inches, and vertically 6 inches. Its shape is some- 
 what oval." 1 From the last statement I infer that the brain 
 in situ may have the mass somewhat more extended than is 
 represented in the figure of Leuret and Gratiolet given above. 
 
 From these important statements bearing upon the physical 
 structure, I pass to the testimony Mr. Sanderson gives con- 
 cerning the disposition and intelligence of the animal. 
 
 As to the general disposition and temper of elephants, our 
 author says: "The elephant stands unrivalled in gentleness." 2 
 " Their good qualities cannot be exaggerated, and their vices 
 are few, and only occur in exceptional animals." 3 "The 
 elephant's chief good qualities are obedience, gentleness, and 
 patience. In none of these is he excelled by any domestic 
 animal, and under circumstances of the greatest discomfort, 
 such as exposure to the sun, painful surgical operations, etc., 
 he seldom evinces any irritation. He never refuses to do what 
 is required, if he understands the nature of the demand, unless 
 it be something of which he is afraid. The elephant is exces- 
 sively timid, both in its wild and domestic state, and its fears 
 are easily excited by anything strange." 4 Mr. Sanderson 
 speaks of the best elephants having " the eye full, bright, and 
 kindly;" but in the worst specimens the "eye is piggish and 
 restless." 5 "Elephants can always be guided, except when 
 frightened, by the slightest tap with a small stick on either side 
 of the head, the pressure of the knee, or even by a word ; but 
 if alarmed, they have to be controlled or urged forward by the 
 driving-goad." 8 
 
 As to intelligence, Mr. Sanderson ranks the elephant decidedly 
 
 1 Thirteen Tears among the Wild Beasts of India, p. 190. 2 lb. p. 62. 
 
 3 lb. p. 81. 4 lb. p. 82. 6 lb. p. 84. « lb. p. 89. 
 
180 THE RELATIONS OF MIND AND BRAIN.. [chap. 
 
 lower than has commonly been done. He says, "he is cer- 
 tainly neither imbecile nor incapable." At the same time this 
 experienced witness considers it an animal not possessed of a 
 high degree of intelligence. " Though possessed of a proboscis 
 which is capable of guarding it against such dangers, it readily 
 falls into pits dug for catching it, and only covered with a few 
 sticks and leaves." 1 If a young elephant fall into a pit, " the 
 mother will remain until the hunters come, without doing any- 
 thing to assist it." " These facts are certainly against the con- 
 clusion that the elephant is an extraordinarily shrewd animal, 
 much less one possessed of the power of abstract thought to 
 the extent with which it is commonly credited. I do not think 
 I traduce the elephant when I say, it is in many things a 
 stupid animal ; and I can assert with confidence that all the 
 stories I have heard of it, excepting those relating to feats of 
 strength or docility performed under its keeper's direction, are 
 beyond its intellectual power, and are mere pleasant fictions." 2 
 He adds : " I have seen the cream of trained elephants at work 
 in the catching-establishments of Mysore and Bengal ; I have 
 managed them myself under all circumstances ; and I can say 
 that I have never seen one show any aptitude in dealing, 
 undirected, with an unforeseen emergency." 3 " The opinion is 
 generally held by those who have had the best opportunities 
 of observing the elephant, that the popular estimate of its 
 intelligence is a greatly exaggerated one, and that instead of 
 being the exceptionally wise animal it. is believed to be, its 
 sagacity is of a very mediocre description. Of the truth of 
 this opinion no one who has lived among elephants can enter- 
 tain any doubt. It is a significant fact that the natives of 
 India never speak of the elephant as a peculiarly intelligent 
 animal ; and it does not figure in their ancient literature for its 
 wisdom, as do the fox, the crow, and the monkey. . . . One of 
 the strongest features in the domesticated elephant's character 
 is its obedience. It may also be readily taught, as it has a 
 large share of the ordinary cultivable intelligence common in 
 a greater or less degree to all animals. But its reasoning 
 faculties are undoubtedly far below those of the dog, and 
 
 1 Thirteen Years among the Wild Beasts of India, p. 80. 
 
 2 lb. p. 80. 3 lb. p. 81. 
 
v.] COMPARISON OF STRUCTURE AND FUNCTIONS. 181 
 
 possibly of other animals ; and in matters beyond the range of 
 its daily experience it evinces no special discernment. Whilst 
 quick at comprehending anything sought to be taught to it, 
 the elephant is decidedly wanting in originality." 1 
 
 The example of brain structure with which I close this 
 chapter is that of the Whale. 
 
 Front. 
 
 Via. 40.— BRAIN OF THE WHALE— EIGHT HEMISPHERE.— 
 
 THE CAAING WHALE (Globicephalus Mdas) i. 
 
 (From Nature, after a Photograph from Specimen in possession of Professor Turner.) 
 
 This is an example of very great interest in its relation to 
 all the problems involved in the comparative anatomy and 
 physiology of brain structure. This interest arises not so much 
 from the size of the organ as from the wonderfully elaborated 
 and beautifully arranged convolutions. The difficulty of the 
 study of this brain is greatly increased by the comparatively 
 small knowledge we can have of the habits of the animal. 
 The only observations we possess on the minute structure of 
 the whale's brain are those recently published by Dr. Major 
 on the brain of the Beluga or white whale. 2 That author has 
 shown that one of the chief differences between the brain of 
 the whale and that of man is a relatively smaller number of 
 large nerve-cells in the third layer of the grey matter of the 
 whale's brain. This inferiority must be considered along with 
 
 1 Thirteen Years among the Wild Beasts of India, p. 7S. 
 
 2 Journal, of Anat. and Physiol., January 1870. 
 
182 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 the distribution of grey matter in much more numerous and 
 minute convolutions — two facts which involve a very important 
 contribution to the materials at command for study of the 
 functions of the brain. 
 
 The interest awakened by the configuration of the brain is 
 heightened by the consideration that the whale ranks among 
 the Mammalia. It is, indeed, popularly classified with fishes, 
 principally because of its form, and also because of its life in 
 the waters. Its real position, however, is among the Mam- 
 malia, as it belongs to the class of animals giving suck to 
 their young. Further, it is an animal which manifests strong 
 affection for its young. These considerations add greatly to 
 the importance of this example of cerebral structure. 
 
 The first point calling for remark is the change of form 
 appearing in this case. The large mass of the cerebrum is 
 placed within the skull in a manner quite different from that 
 seen in the case of quadrupeds such as the dog, horse, or 
 elephant, and also different from that found in cases where the 
 bodily structure is such as to admit of an erect, or even semi- 
 erect posture on two feet. It is laid along the back region of 
 the head in such a manner that the Sylvian Fissure (S), takes 
 its rise from the anterior region of the cerebrum, and just 
 above the cerebellum (Cm), instead of taking its rise from the 
 base of the cerebrum, and in front of the cerebellum, as in the 
 other cases represented. The position is altogether strange. 
 The formation of the skull differs proportionately with that of 
 the brain, the bones of the face being extended, and the 
 cranium flattened and elongated. 
 
 The brain of the whale, though large in the scale of brains, 
 is decidedly small relatively to the size and weight of the 
 animal's body. Some estimate in these respects may be 
 formed from the account given by Dr. Scoresby of the observa- 
 tions as to a young whale of comparatively small dimensions, 
 so that the animal was lifted completely on deck. The 
 fact that the largest whales are cut up while floating in 
 the water makes it impossible in their case to take accurate 
 measurements. The young whale referred to by Dr. Scoresby 
 was "19 feet in length, and 1 4 feet 5 inches in circumfer- 
 ence." I give entire Dr. Scoresby's passage as to the brain : 
 
v.] COMPARISON OF STRUCTURE AND FUNCTIONS. 183 
 
 "The brain, lies in a small cavity in the upper and back 
 part of the skull. The cavity included within the pia mater, 
 exclusive of the foramen magnum, measured only 8 inches 
 by 5. The upper part of the brain lies very near the sur- 
 face of the skull. The convolutions of the cortical substance 
 lie in beautiful fringed folds, attached to the medullary portion, 
 which is white, as in the human brain. The general appear- 
 ance of the brain is not unlike that of other Mammalia, but its 
 smallness is remarkable. The quantity of brain in a human 
 subject of 140 or 160 pounds weight is, according to Haller, 4 
 pounds; in this whale of 11,200 pounds (5 tons), or seventy 
 times the weight of a man, the brain was only 3 pounds 12 
 ounces. According to Cuvier, the brain in man varies from 
 one thirty-first to one twenty-second part of his weight, 
 whereas in this animal the proportion of brain was only a 
 three-thousandth part." 1 
 
 The most striking feature of this brain is the wonderfully 
 intricate arrangement of convolutions. . Nothing in the scale of 
 brain structure which has come before us in the preceding 
 course of observation, approaches it in minuteness of folding. 
 This intricacy of superficial arrangement must be set over 
 against the small size of the organ. If we are correct in 
 regarding it as a law in brain structure, that folding of the 
 convolution is the method employed for increasing the area 
 of grey matter within the cavity of the skull, that law has 
 most striking illustration here. The nervous system connected 
 with the organ does not appear to be complicated, being mainly 
 connected with two organs of special sense, sight and hearing, 
 and stretching down the spinal cord to embrace the muscular 
 system, which is huge in proportion, rather than intricate in 
 arrangements. In the young specimen described by Dr. 
 Scoresby, the length of the body was 1 9 feet, while the length 
 of the cavity containing the brain was only 8 inches. In a 
 paper read before the Wernerian Society, the same author 
 says: "The whale, when full grown, is from 50 to 65 feet in 
 
 1 Journal of a Voyage to the Northern Whale-Fishery in 1822, p. 150. 
 Dr. Scoresby remarks that the proportion between brain and body in man 
 is less on an average than that given by Cuvier. This is confirmed by what 
 has been already stated, p. 22. 
 
184 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 length, and from 30 to 40 in circumference immediately before 
 the fins." 1 Taking the maximum length here mentioned, and 
 estimating the cranial cavity at the same proportion as in the 
 young whale (in all probability it will be somewhat larger), we 
 have 27 inches, or a little over 2 feet, as the length of the 
 cranial cavity, while " the jaw-bones, the most striking portions 
 of the head, are from 20 to 25 feet in length; 2 and the entire 
 body from 60 to 65 feet. The brain is, therefore, small in 
 length relatively to the extent of the body. But what is 
 wanting in length is made up in complexity. Division into 
 lobes similar to those found in other orders could not be 
 attempted in this case; and yet, in addition to the great 
 Sylvian fissure, there are obviously certain deeper sulci break- 
 ing off from the Sylvian fissure, which may be found to have 
 some value for purposes of subdivision, if greater familiarity 
 with the organ were attained. Meanwhile, however, it may 
 be regarded as certain that the great multitude of grooves, and 
 singular minuteness of folds, point to a proportionate increase 
 in area of the grey matter, and suitable provision for blood 
 supply. And, if these things be admitted, we have a further 
 indication of the conclusion, supported by the brain of the 
 elephant, that cerebral structure has at least one measure of 
 the intricacy of its convolutions in the mass and power of the 
 muscular system which it controls. Some estimate of the 
 muscular power of the whale may be formed from what Dr. 
 Seoresby has said in the following passage as to the small 
 cub or " sucker " already referred to : — " The muscles about 
 the neck appropriated to the movements of the jaws, formed 
 a bed, if extended, of nearly 5 feet broad and 1 foot thick. 
 The central part of the diaphragm was 2 inches in thickness. 
 The two principal arteries in the neck (the carotid) were so 
 large as to admit a man's hand and arm." 3 
 
 The other parts of the body which are of most interest as 
 bearing on the muscular strength of the animal are the fins 
 and tail. Dr. Seoresby, speaking in this case of the full-sized 
 whale, says, "The fins are from 4 to 5 feet broad, and 8 or 10 
 
 1 Memoirs of the Wernerian Society, vol. i. p. 578. 
 
 2 lb, p. 579. 
 
 3 Journal of a Voyage, p. 150. 
 
v.] COMPARISON OF STRUCTURE AND FUNCTIONS. 185 
 
 feet long, and seem only to be used in bearing off their young, 
 in turning, and giving a direction to the velocity produced by 
 the tail." The anterior extremities are of a formation which 
 warrant their being spoken of as rudimentary arms, the bones 
 being somewhat analogous to those of the fore limb in other 
 mammalia. They are sometimes named "paddles," and not 
 inappropriately it was suggested by the Eev. John Fleming, 
 when describing a Narwhal cast ashore in Zetland, that they 
 might be named " swimming-paws." 1 
 
 In explanation of the propelling power, Dr. Scoresby thus 
 describes the tail of the full-grown animal — " The tail is hori- 
 zontal, from 20 to 30 feet in breadth, indented in the middle, 
 and the two lobes pointed and turned outwards. In it lies the 
 whole strength of the animal. By means of the tail the whale 
 advances itself in the water with greater or less rapidity; if the 
 motion is slow, the tail cuts the water obliquely, like forcing a 
 boat forward by the operation of sculling ; but if the motion is 
 very rapid it is effected by an undulating motion of the rump." 2 
 
 As to the special senses, Dr. Scoresby says, " The eyes are 
 very small, not larger than those of the ox, yet the whale 
 appears to be quick of sight." 3 The organ of vision is protected 
 by a peculiarly strong sclerotic coat. Dr. Scoresby adds, " In 
 the whale the sense of hearing seems to be rather obtuse." In 
 the Journal of a Voyage (p. 154), the following interesting 
 additional information is given: — "The whale has no external 
 ear ; and the opening of the passage to this organ is so small, as 
 not to be easily discovered. In the sucking whale it is only one- 
 sixth of an inch in diameter. An elegant contrivance appears in 
 the meatus auditorius externus, for protecting the ear against 
 pressure from without. It consists of a little plug, like the end 
 of the finger, inserted in a corresponding cavity in the midst of 
 the canal, by a slight motion of which the opening can either 
 be effectually shut, for the exclusion of the sea-water, or un- 
 closed for the admission of sound." 
 
 The female whale shows strong affection for its young. Dr. 
 Scoresby says : " Its maternal affection deserves notice. The 
 young one is frequently struck for the sake of the mother, 
 
 1 Memoirs of the Wernerian Society, vol. i. p. 1 34. 
 
 2 lb. p. 580. 3 lb. 
 
186 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 which will soon come up close by it, encourage it to swim off, 
 assist it, by taking it under its fin, and seldom deserts it 
 while life remains. It is then very dangerous to approach, as 
 she loses all regard for her own safety in anxiety for the pre- 
 servation of her cub, dashing about most violently, and not 
 dreading to rise even amidst the boats." \ 
 
 In the course of these investigations as to the results of 
 comparative anatomy and physiology, as bearing on brain 
 structure, I have repeatedly had to speak of the degree of 
 intelligence manifested by different animals. I do not attempt 
 to unfold any theory as to the intelligence thus manifested. 
 I do not inquire how far the actions of animals may be 
 regarded as reflex, and how far otherwise the organism may be 
 considered automatic. The question is too large and too beset 
 with perplexities, to be treated as a side issue in such a work 
 as the present. I am contented, therefore, with indicating that 
 my main argument is not affected by the theory which may be 
 adopted as to animal intelligence and activity. Whether 
 animals be regarded as mere automata, or a soul be attributed 
 to those obviously high in intelligence, the evidence on which 
 I depend, and the argument which I am endeavouring to con- 
 struct, are not essentially modified. 
 
 1 Memoirs of Wernerian Society, vol. i. p. 585. For structure and propor- 
 tions of the skull of the whale, see Professor Turner's Account of the Great 
 Firmer, Whale (Balaenoptera Sibbaldii) stranded at Longniddry. — Transac- 
 tions of the Royal Society of Edinburgh, vol. xxvi. p. 197 : and, by the 
 same author, paper On the occurrence of Ziphius eavirostris in the Shetland 
 Seas, and a comparison of the Skull with that of Sowerby's Whale. — Trans. 
 Roy. Soc. Ed., vol. xxvi. p. 759. 
 
VI.] ANATOMICAL AND PHYSIOLOGICAL RESULTS. 187 
 
 CHAPTER VI. 
 
 KESULTS OF ANATOMICAL AND PHYSIOLOGICAL INVESTIGATIONS. 
 
 A stage has now been reached in course of this inquiry which 
 makes it desirable that we should take a general survey of the 
 position. The ground which has been gone over is extensive, 
 and there is need for retrospect, with the view of obtaining a 
 harmonious conception of the results. • The range of inquiry 
 still before us is large, and what remains to be done depends to 
 a great extent for its satisfactory accomplishment on keeping 
 clearly before us the more prominent features of the investi- 
 gations already made. A summary of results, therefore, seems 
 an essential requisite at this stage, with the view of formally 
 recognising what things have been proved and what things 
 remain unproved. 
 
 The first and most general result is, that there is similarity 
 of structure and function of the nerve system in all animal life. 
 In every case the nerve system consists of two sets of fibres, 
 sensory and motor, uniting in a centre, which may be a single 
 cell, or a mass of cells. The homology is clear and undisputed. 
 
 The structure of the nerve fibres is the same, though their 
 functions so far differ that some are sensory, others motor. The 
 contrast of function does not arise from diversity in the fibre, 
 but from difference in the terminal arrangements. The sole 
 distinction is found in the fact that those fibres which are 
 motor in function are distributed to the muscular system, while 
 the sensory are distributed to the skin, and organs of special 
 sense, and are provided with terminal organs sensitive to a 
 variety of external impressions. 
 
 The nerve centre itself is in all cases composed of the mass 
 of nerve fibres brought to unity at the central terminus, and 
 a mass of grey cellular matter conjoined with the collected 
 fibres. These two substances are united in every example of 
 
188 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 a nerve centre. The function of the grey matter is to evolve 
 the nerve energy, needful for the activity of the nerve 
 fibres. 
 
 While the nerve centre is analogous in structure in all cases, 
 there is great diversity of arrangement as we ascend the 
 scale of animal life. Only in the lowest forms of organism is 
 the nerve centre a single ganglionic mass. As the muscular 
 system increases in complexity, so does the nerve system, and 
 as the nerve system becomes more complex, so does the nerve 
 centre. This complexity of the nerve centre wears two aspects ; 
 first, the multiplication of ganglia which unitedly constitute the 
 central system; and second, more involved or elaborated structure 
 of the cerebrum or brain proper, as the chief organ in the central 
 system. In the vertebrates, the central system has its lower 
 extreme in the spinal cord, its higher extreme in the cerebrum. 
 Every distinct nervous mass lying between these has its own dis- 
 tinct share of cellular tissue. The medulla, pons, and cerebellum 
 have their own appropriate supply, as well as the spinal cord 
 and the cerebrum. Within the cerebrum itself, the basal ganglia 
 and the lobes of special sense illustrate a further application 
 of the same rule, for they also are distinct formations, with 
 their own share of grey matter. There is therefore considerable 
 variety of arrangement connected with the distribution of the 
 cellular matter. But this does not imply diversity of function. 
 There seems no evidence pointing towards the conclusion that 
 there is an essential difference in the substance, according to 
 its relative position in the central system. Everywhere it is 
 cellular, everywhere it is situated in direct relation with nerve 
 fibres, and everywhere it evolves nerve energy, which is 
 discharged along those nerve fibres in immediate connection 
 with it. When the cellular substance of the brain proper is 
 placed under the microscope, there is found to be some differ- 
 ence in the minute structure of parts. Thus, the neuroglia 
 is more abundant in the outer layers, and the nerve cells 
 less numerous ; whereas, in the layers more deeply situated, 
 the cells are not only more numerous, but larger in size. 
 Still, these diversities do not imply anything more, so far as 
 evolving nerve energy is concerned, than a lower or higher 
 degree of power in fulfilling a common function. It is not 
 
VI.] ANATOMICAL AND PHYSIOLOGICAL RESULTS. 189 
 
 implied that the grey matter gathered in separate masses fulfils 
 four distinct functions, according as it is found in the medulla, 
 pons, cerebellum, or cerebrum. So far as anatomical and 
 physiological results guide us, there is no evidence on which 
 to maintain an essential difference either of structure or of 
 function. Every cell evolves nerve energy. Of these cells there 
 are two chief classes, the one sensory, the other motor. The 
 sensory cell is receptive of influence from without. The motor 
 cell gives rise to an impulse which is carried downwards to 
 the muscular system. 
 
 Here arises the problem as to the kinds of work done by 
 nerve cells and nerve fibres. Much uncertainty still hangs 
 over the molecular changes which go on in the cellular mass 
 constituting the common feature of a nerve centre. What 
 is known naturally raises the question, — how much can be 
 done by nerve cells 1 We must seek at least to approxi- 
 mate towards a determination of the limits of functional 
 activity in this case, knowing that cells perform very different 
 functions in different parts of the body. Some precise know- 
 ledge we must have of the work daily executed by the brain, 
 for only thus can we advance towards a conclusion combining 
 the testimony of anatomical and physiological science on the 
 one hand, and of mental philosophy on the other, as to the 
 intelligence and will-power which together perform so con- 
 spicuous a part in human life. 
 
 The accompanying diagrammatic representation will aid our 
 attempt to summarise results. 
 
 M^ 
 
 Fig. 41. -DIAGRAMMATIC REPRESENTATION OF THE RELATIONS OF MOTOR 
 AND SENSORY CELLS. 
 
 M, Motor apparatus ; e, Motor cell ; n, Nerve ; m, Muscle. S, Sensory apparatus ; c, Sensory 
 cell • m Nerve ; s, Sensory corpuscle, as in touch. The arrow Indicates, in each case, 
 the direction in which the impulse is conveyed. 
 
190 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 The distinction between the motor and sensory arrangement 
 is found in the contrast of peripheral structure. The cell and 
 the nerve are common to both. The difference is, that there 
 is at the outer extremity of the fibre in one case a muscle, in 
 the other a touch-corpuscle, or other sensitive terminal organ. 
 The composition of the nerve is, as we have said, the same in 
 both, and no distinction has been recognised between the cells 
 other than that which is found in their relation to a particular 
 nerve fibre. While, however, the contrast between the two 
 arrangements is found at the outer extremity of the nerve 
 fibre, the shock or impulse which brings the fibre into action 
 is delivered at the opposite ends of the line. In the case of 
 the motor nerve, the impulse which originates activity is 
 delivered at the end where the cell is, and the consequent 
 motion is downwards. In the case of the sensory nerve, the 
 shock or impulse is delivered where the touch-corpuscle, or 
 other peripheral terminal organ, is placed, and the movement 
 communicated to the nerve fibre takes an upward course. 
 I begin with the Sensory Apparatus. Excitability belongs to 
 the corpuscle or other terminal organ, fitting it for impulse 
 or shock from without. We know that ordinary tactile im- 
 pression will communicate an impulse to the touch-corpuscle, 
 — that light will find a sensitive terminal organ in the retina, 
 though nowhere else in the body, — and that sound-waves will 
 find their sensitive part in the slender nerve fibres set up in 
 the third or inner chamber of the ear. There is diversity of 
 terminal arrangement in the three cases, providing for different 
 forms of tactile impression, but in all the three an impulse 
 is communicated to the terminal organ, and a movement 
 takes place up the nerve fibre. This movement of the fibre 
 must result in some movement, impression, or change in 
 the cell connected with the sensory nerve, and this must in 
 some way represent the impression at the periphery. We 
 must, however, begin with the fibre, and its movement, under 
 the shock delivered at the periphery. And here there are 
 two essential features. First, the sensory nerve is main- 
 tained in the sensitive condition which constitutes prepared- 
 ness for nerve action, only by direct vital relation with the 
 cell. This is a feature common to the sensory nerve and the 
 
VI.] ANATOMICAL AND PHYSIOLOGICAL RESULTS. 191 
 
 motor. Second, the movement in the sensory nerve is the 
 result of impulse communicated from without the nerve 
 system, not from within. This forms a contrast to what is 
 true of the motor nerve. As to the vitalising or innervating 
 influence coming constantly from the cell to the fibre, it seems 
 unnecessary to speak particularly, since it is a common charac- 
 teristic of the whole nerve system. 
 
 There remains, therefore, the problem raised by the impulse 
 or shock communicated to the sensory nerve. This problem 
 includes these elements— excitability at the peripheral extre- 
 mity, movement along the nerve fibre, molecular action of the 
 nerve, cell resulting from movement along the nerve fibre, and 
 sensation as a matter of experience. Each one of these four 
 in reality presents a distinct problem. Only by harmonious 
 solution of the four can we have a scientific explanation of the 
 activity of a sensory nerve. It may be well therefore briefly 
 to state what present knowledge seems to warrant. 
 
 1. Active sensibility at the peripheral extremity depends 
 upon three things, — vital relation of the peripheral organ with 
 the nerve cell ; adaptation of structure in the peripheral organ 
 to tactile influence ; direct contact with some external surface. 
 The general tactile sense may be taken as illustrating all sensory 
 activity. The two first-named elements are the common requi- 
 sites for tactile impressions. The last-named is that which is 
 the immediate occasion of an exercise of sensibility. "With 
 those facts must also be taken the additional facts Connected 
 with our experience of pain, for these must have a conspicuous 
 place in connection with a theory of the action of sensory 
 nerves. While ordinary tactile impression is agreeable and 
 compatible with uniform exercise of the nerve as a means of 
 knowledge, application of force, as from a blow, or an im-- 
 pression which penetrates through the skin to the terminal 
 organ, as the prick of a needle or a cut, occasions pain, the 
 severity or acuteness of which is incompatible with the ordinary 
 use of the sensory corpuscle, as an instrument of knowledge. 
 If instead of touch we have violent concussion or actual 
 injury, there is temporary interference with the normal use of 
 the sensory nerve as an instrument of knowledge. Taking 
 together the ordinary tactile impression, which is agreeable, 
 
192 THE RELA TIONS OF MIND AND BRAIN. [chap. 
 
 and the very familiar experience from the shock or injury 
 which occasions pain, the sensibility of the peripheral organ 
 seems to carry a large part of the explanation of the move- 
 ment along the nerve fibre. In the one case there is a quiet, 
 rhythmic movement ; in the other a disturbed, convulsive move- 
 ment. Whether the movement along the nerve fibre is an 
 example of molecular movement or not, does not materially 
 affect the problem. But in constructing a theory of sensa- 
 tion we must take into account such facts as these — that 
 slightness of tactile impression is sufficient to secure activity of 
 the sensory nerve ; that there is necessity for a comparatively 
 slight impression, in order to maintain the normal function of 
 the fibre as an instrument of knowledge ; and that a shock of 
 considerable force, or actual injury to the terminal bulb, or 
 coil, or other organ, occasions convulsive movement, incon- 
 sistent with the normal action of a sensory nerve. Excita- 
 bility in the corpuscle, and conductivity in the fibre, are 
 essential and distinct features accounting for the movement, 
 which results in that form of experience known as sensation. 
 "With increase of excitation coming from without, there is 
 increase in sensation according to a logarithmic ratio. Beyond 
 a given point pain supervenes, from which it follows that the 
 normal action of the sensory corpuscle is restricted to the 
 lower degrees in the scale of impression. 
 
 2. Action of the corpuscle, or other terminal organ, occasions 
 movement of the correlated sensory fibre. The movement of 
 the terminal organ acts upon the conductivity of the fibre, and 
 on account of the presence of nerve energy or nerve fluid, sup- 
 plied from the nerve cell, the impression conveyed to the fibre 
 does not merely influence the lower end of it, and gradually 
 pass off, but the movement is propagated with equal facility 
 up the whole length of fibre. This propagation of nerve in- 
 fluence, indicated by movement in the nerve fibre, takes 
 effect quite irrespective of the length of the fibre brought into 
 action. The length is according to the distance of the terminal 
 organ from the nerve centre. In the case of the general tactile 
 sense, the length varies according to the surface of the body, 
 some fibres stretching to the fingers, others to the toes. With 
 all the special senses the nerve fibres are short, for the terminal 
 
vi.] ANATOMICAL AND PHYSIOLOGICAL RESULTS. 193 
 
 organs are all situated in the region of the head, where com- 
 munication is very direct. According to variations in length 
 there will be variations in the time required for propagation of 
 the movement, in accordance with calculations such as those 
 of Helmholtz. But the conducting of impressions along the 
 nerve is accomplished with facility whether the line be long 
 or short. 
 
 3. Action of the correlated nerve cell must be the result of 
 the impulse being conveyed along the nerve line. It is not 
 affirmed that the movement here referred to has been matter of 
 direct observation, as in the case of the two preceding facts. 
 But it is matter of the clearest inference, supported not only 
 by the whole analogy of the nerve system, but by a series of 
 clearly verified facts which imply it. As the nerve has its 
 central terminus in the cell, the movement propagated along 
 the line must cause vibration or movement of the cell. The 
 impulse communicated to the corpuscle implies a shock to the 
 cell. And the whole three actions, that of the corpuscle, that 
 of the nerve, and that of the cell, must imply waste of nerve 
 power, and consequent need for restoration. The pheno- 
 mena of pain confirm the conclusion as to the action of the 
 nerve cell. In a manner analogous with reflex action, there is 
 sensori-motor action. If a needle punctures the skin, there is 
 convulsive movement of the sensory nerve, and in immediate 
 connection with it a wave of nerve force sets the motor 
 apparatus into action, and the finger is instantly withdrawn. 
 In this case, we are assured of movement of the sensory cell, 
 and also of communicated movement to a motor cell, liberating 
 nerve force which brings the motor fibre into exercise, causing 
 action of the muscle and withdrawal of the hand. A connec- 
 tion between a sensory cell and a motor cell being thus shown to 
 exist, it is clear that such connection must be much more widely 
 established than between a single sensory cell and a single 
 motor cell. It is of no consequence whether the thumb or any 
 one of the fingers suffers from a prick, the exact locality of 
 the injury can be recognised, and the instant withdrawal of the 
 hand will result. Nor is this all. As a consequence of the 
 prick, the muscles of the face will be brought into action, and 
 the expression of pain will at once appear. There must, there- 
 
 N 
 
194 THE KELA TIONS OF MIND AND BRAIN. [chap. 
 
 fore, be an intricate arrangement of connecting fibres, between 
 sensory and motor cells, by means of which a single movement 
 along the sensory nerve may result in a whole series of move- 
 ments, propagated in different directions. It is, indeed, true 
 that a person may restrain the facial expression, so as to avoid 
 giving outward signs of his suffering other than that involved 
 in the withdrawal of his hand. But this only suggests a still 
 wider system of connection between a sensory cell and motor 
 apparatus. Tor the restraint of expression on the face indicates 
 another movement to prevent a movement which would 
 naturally arise if it were not restrained. There is thus an in- 
 hibitory power over muscular activity, the elucidation of which 
 will show still more strikingly that a single sensory cell must, 
 by distinct fibres, have established relations with numerous 
 branches of motor apparatus. A concealed movement here 
 provides for the concealment of feeling which otherwise would 
 have found expression in the countenance. These considera- 
 tions illustrating connection with a large number of motor cells 
 through means of a single sensory cell, indicate faintly how 
 numerous must be the connecting lines within the brain, 
 placing the sensory and motor cells in active relations. 
 
 4. A definite form of experience, known as a Sensation, is 
 the result of the action of the sensory apparatus. If the 
 normal rhythmic action of the nerve take place, the sensation is 
 agreeable, and conveys to us some knowledge of the object 
 brought into tactile relation with the finger or other part of the 
 body. If the disturbed, convulsive movement take place, the 
 sensation is painful and disturbing, preventing us from making 
 ordinary use of the sensory nerve as an instrument of know- 
 ledge. Whether the sensory cell has sensibility such as 
 belongs to the touch corpuscle has not been established. 
 That it is liable to molecular change must be admitted ; that 
 this implies movement in the cell, and also the possibility of 
 communicating movement to a motor cell, we have just seen ; 
 but that the nerve tremor or action in the nerve cell implies 
 sensibility, has not been made out. Many things seem adverse 
 to the supposition, while some things may appear to favour it. 
 I have already referred (p. &1) to the fact that protruding 
 portions of the brain have been cut away without sense of pain, 
 
VI.] ANATOMICAL AND PHYSIOLOGICAL RESULTS. 195 
 
 thereby showing that there is not tactile sensitiveness in the 
 central organ such as there is in the peripheral terminal 
 organ, nor liability to pain as in the sensory fibre. Further, 
 we must take account of the fact that no essential difference 
 has been discovered between the sensory cell and the motor 
 cell other than their relation to distinct arrangements of nerves. 
 This seems to preclude us from saying that there is any 
 sensibility in the sensory cell which is not also in the motor. 
 It is, however, admitted that an impulse communicated to the 
 touch-corpuscle is conveyed to the sensory nerve cell. This, at 
 the very least, implies movement in the nerve cell, which, how- 
 ever, may be propagated to a motor cell, and thence extended, 
 so that muscular action may be the result. We are thus 
 led to infer that if we may assign a species of excitability 
 to the sensory cell, we must also assign a similar excitability 
 to the motor cell. But, on the other hand, there is a 
 purely sensory movement altogether unattended by motor 
 activity : that is, there is a movement stirred in the sensory- 
 cell which is not conveyed to an associated motor cell ; at least 
 there is no outward sign of its being so conveyed. We are, 
 therefore, warranted in concluding that there is a movement 
 which terminates with the - sensory apparatus, or if it be 
 carried further along the connecting fibres towards the motor 
 cells, it tends to die away, and does not lead to functional 
 activity beyond. It is the movement or action within the 
 sensory cell which is the final result in the sensory apparatus ; 
 and this result must be either the very thing we mean by a 
 sensation, or the necessary precursor and accompaniment of the 
 sensation. Whether the movement within the cell and the 
 experience known as a sensation are to be identified or regarded 
 as distinct is a question which will be considered hereafter. 
 But at the very least the general conclusion may be expressed 
 in these words : — " The cells undergo certain molecular modifi- 
 cations, which coincide with certain subjective changes consti- 
 tuting the consciousness of the impression." 1 As to sensibility 
 of the cell, we may conclude that there is neither such sensi- 
 bility as in the terminal organ liable to tactile impression from 
 a foreign body ; nor sensibility to pain as the result of injury, 
 1 Ferrier's Functions, p. 257. 
 
196 THE RELA TIONS OF MIND AND BRAIN. [chap. 
 
 though there may be a form of sensibility not represented for 
 us by action of the touch-corpuscle or of any similar terminal 
 organ. Contenting ourselves with this conclusion as the closest 
 approximation which can be reached, we may further remark 
 a more extended illustration of widely established relations 
 between a sensory cell and a large circle of motor cells. When 
 the sensory apparatus is in action, and a given amount of 
 knowledge is obtained concerning the nature of the objects 
 coming into contact with our hand, our feeling finds expression 
 on the face, according as we experience aversion, wonder, or 
 special delight. And this adaptation of muscular action suit- 
 able for emotional expression is so far from being in any sense 
 an intellectual or voluntary act, that it takes place before 
 we are aware of it, and requires a voluntary restraint to be 
 placed on muscular action, if the expression is to be prevented. 
 In view of this additional motor result attending on action of 
 the sensory apparatus, we are led to accept a still wider re- 
 presentation of the motor relations which must be established 
 with each one of the sensory cells. In view of the relations 
 suggested by the experience dependent on the use merely of 
 the hand as an organ of touch, there must be multitudes of 
 motor centres in the human brain beyond those identified 
 or even suggested by electric stimulation of the brains of the 
 lower animals. 
 
 If now we pass to the motor apparatus, we have an arrange- 
 ment exactly analogous to that of the sensory system, save that 
 a muscle occupies the place of the peripheral sense-organ. This 
 difference, however, implies an entire difference of function, 
 though the two forms of apparatus are placed in intimate vital 
 relation. The essential contrast in activity appears in this : 
 that the impulse or shock which sets a distinct motor line 
 in action is delivered at the cell, that is, in the nerve centre, 
 and not at the extremity. Here the nerve cell is doing what 
 the sensory cell does not accomplish, and which, nevertheless, 
 the sensory cell may act upon the motor cell to induce it to 
 accomplish. The latter consideration it will be better to 
 reserve until we glance at the exact results concerned with 
 purely motor activity. Here, however, we cannot bring the 
 facts under our observation as in the former case. The begin- 
 
VI.] ANATOMICAL AND PHYSIOLOGICAL RESULTS. 197 
 
 ning or rise of motor activity is most obscure and uncertain. 
 An impulse or shock must somehow be given to the motor cell. 
 Whatever be the conditions of life belonging to a cell, it is not 
 suggested that the motor cell is always functionally active any 
 more than the sensory cell. There is a beginning of activity 
 which needs to be explained. This beginning may be occa- 
 sioned either by the action of a sensory cell upon the motor 
 cell, in the manner already described, or by a volition, as when 
 a person voluntarily raises his arm. What is involved in this 
 volition which causes the action of a motor cell will be con- 
 sidered in a subsequent chapter. It is enough for the present 
 that we note two distinct modes of bringing the motor cell 
 into exercise for the propagation of movement down the motor 
 nerve. The order of events to be considered is the following: — 
 There is movement within the motor cell ; there is discharge of 
 nerve energy down the motor nerve ; there is consequent action 
 upon the muscle, liberating the energy which is stored there, 
 and which is greater than the nerve energy which acts upon it ; 
 and there is movement of the arm, or of the finger, or of. the 
 extremity of a finger, as the case may be. 
 
 1. By some impulse or shock given to the motor cell it is 
 brought into activity, so as to evolve nerve energy. For origin 
 of this cellular action there is need of some influence external 
 to the cell. It is not suggested that each motor cell is subject 
 to some general graduated scheme of vital action applicable to 
 the whole motor system, and providing for regular rhythmic 
 movement of all the cells in turn. All cells alike depend upon 
 a general scheme of nourishment, so that it may be said that 
 all the action and reaction of the sensori-motor system comes 
 by chemical process from the supplies of food and drink re- 
 ceived into the stomach. But, this common type of depend- 
 ence, or common source of activity, being granted, as a physical 
 condition of the possibility of sensory and motor activity, it is 
 admitted that there is need for a special explanation of each 
 example of motor activity. And this explanation must begin by 
 accounting for the evolution of nerve energy by a motor cell at 
 a given moment. As we have seen, there are two perfectly 
 distinct forms of explanation. First, The origin of movement 
 in the motor cell is accounted for by communication of impulse 
 
198 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 from a sensory cell. The sensory cell, being itself thrown into 
 action by impulse received at the peripheral organ, sends for- 
 ward the impulse to the motor cell, thereby giving a shock to 
 the motor cell, under the influence of which nerve energy is 
 evolved. In such a case the real origin of activity is the ex- 
 ternal impulse. The sensory activity, and attendant motor 
 activity, illustrate a type of spontaneous action belonging to 
 all living organisms. Such organism is thus shown to be, 
 within certain limits, a self-adjusting mechanism, operated 
 upon from without. In this respect the nerve system is the 
 same, in whatever animal organism it exists. There is a law 
 of sensori-motor activity which is common to all animal exist- 
 ence, and is illustrated in our own movements, exactly as in 
 the actions of the lower animals. Any difference which here 
 appears between ourselves and the animals, arises from evidence 
 that the sensori-motor system is more fully placed under con- 
 trol in our experience than in the case of the animals. This is 
 illustrated by a greater degree of inhibitory power exercised 
 by man over the sensori-motor system — a fact which points to 
 a higher form of control, to be introduced under the second 
 division of this statement. It only remains to be added here, 
 that stimulus coming from physical appetite, such as hunger, 
 illustrates the same law of sensori-motor action, as appears 
 consequent on excitation beginning at the periphery. Second, 
 Origin of movement in the motor cell is further accounted 
 for by communication of impulse from some inner sphere, 
 quite apart from the action of a sensory cell. There is an 
 originating impulse which cannot be accounted for by the 
 action of the sensori-motor system. The movement of the legs 
 while walking can be explained by the law of sensori-motor 
 activity. The movement of the fingers in writing cannot be 
 so explained. Accordingly, use of the eyes is much more con- 
 stant in writing than in walking, and much more minute in 
 application. This implies more observation as to what is being 
 done in wielding the pen, and such observation is correlated 
 with thought and volition in a manner quite unknown in mere 
 sensori-motor activity. The pen is giving outward expression 
 to thought, which would otherwise be left without any ex- 
 ternal manifestation, and is not caused by sensory impressions ; 
 
vi.] ANATOMICAL AND PHYSIOLOGICAL RESULTS. 199 
 
 and it is doing so by means of muscular action resulting 
 from impulse communicated by the Will to the motor cell. 
 Whether there may be anything in animal life analogous to 
 this, it may be difficult for us to decide. The lower animals 
 certainly give very few indications which warrant classifica- 
 tion of their actions under this head, whereas all the more 
 important actions of man involving use of muscular energy 
 may be so classified. In human life the simplest exercises of 
 muscular power commonly illustrate power of will, while all 
 the higher forms of skilled labour are impossible without it. 
 Higher intellectual exercises run up into a region more remote 
 from muscular^ action, with which alone I am now dealing. 
 How an exercise of Will communicates an impulse to the 
 motor cell is unknown. What the impulse from volition 
 effects can be nothing more than movement in the nerve 
 cell, resulting in liberation of the nerve energy which that 
 cell evolves. 
 
 2. By action of the motor cell the nerve energy is trans- 
 mitted down the motor nerve. This nerve is thus a com- 
 municating fibre between the motor cell and the muscle. The 
 structure of the motor nerve is the same as that of the sensory- 
 nerve, and the action is the same, though the direction of the 
 impulse is the opposite. There is therefore no need for special 
 remark at this point. 
 
 3. By impulse conveyed along the motor nerve muscular 
 energy is liberated, and a new power is brought into action. 
 In accordance with the position (p. 79) established by Haller, 
 that contractility of muscle does not depend upon the motor 
 nerve, though acted upon by its instrumentality, a new and 
 more powerful form of energy is brought into application. The 
 muscle can do work which the nerve cannot perform, yet the 
 nerve impulse liberates the muscular energy, sets it in action, 
 and is sufficient to keep it in action, until a sense of exhaustion 
 gives warning of the need for rest and nourishment. Thus we 
 nave, in connection with the motor apparatus, an entirely dis- 
 tinct feature in the working of the nerve system. The nerve 
 energy discharged from the motor cell accounts for the mus- 
 cular action, in so far as it explains its origin ; arid this is the 
 primary and essential point, without which no action would 
 
200 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 take place. But, on the other hand, the nerve energy is insuf- 
 ficient to account for the resultant action, which is explained 
 by a form of energy belonging to the muscle itself, and depend- 
 ing on the property of contractility belonging to muscular 
 tissue. Professor Tait has put the distinction admirably in 
 these words : — " It seems, from the observations of physiologists 
 as to the formation of cellular matter, and the production in 
 living organisms of compounds which have not yet been made 
 by ordinary chemical processes, that the vital force, if there be 
 such [let us say, ' nerve force '], is not a force which does work, 
 but merely directs, as it were, the other natural forces how 
 to apply their energies.' . . . 'When gangs of labourers and 
 masons are at work building an edifice, the former are em- 
 ployed raising stones, mortar, etc., the latter in laying them ; 
 but there is present an overseer with a plan, who, doing no 
 (mechanical) work himself, guides and directs the proper 
 expenditure of force by the working body. In this view of 
 the case, the labourers are the physical forces, and the overseer 
 the vital force." 1 So Nerve Energy is the overseer with the 
 plan, who does no mechanical work, but directs the muscular 
 energies ; and Intellect is the architect who draws the plan. 
 As, then, the outstanding characteristic of the sensory appa- 
 ratus is sensibility to external influence, that of the motor 
 apparatus is power to do work in an external sphere. If there 
 be a distinct kind of work, known among us as " intellectual 
 work," that does not appear to be provided for by either the 
 sensory or the motor apparatus. 
 
 We must not, however, pass from muscular activity without 
 noticing certain facts associated with it, which throw light on 
 the intricate relationship established between perfectly distinct 
 nerve cells. A large proportion of our muscular activity is 
 attended by constant use of the organs of vision in order to 
 provide for direction. This fact implies a very large number 
 of cells placed by connecting fibres in relation with the motor 
 cells concerned with the ordinary use of the eyeball. All 
 muscles directed by aid of sight must be placed in some rela- 
 tion with the six muscles which control the eyeball, so as to 
 secure co-ordination of movement. Besides, along with the 
 
 1 Article Force ; Energy. Chambers's Encydopcedia. 
 
VI.] ANATOMICAL AND PHYSIOLOGICAL RESULTS. 201 
 
 regulation of muscular movement by aid of vision, there is 
 frequent expression on the face of interest, surprise, or other 
 emotion. Such expression is largely indicated by action of the 
 eyebrows, and this implies a further relationship of nerve cells, 
 in order to bring into co-ordinated action the four muscles of 
 the eyebrows specially concerned in such expression. This 
 emotion implies a form of intellectual action which we have 
 seen is not accounted for by the two forms of nerve apparatus, 
 and thus the expression of emotion by the eyebrows implies 
 some further relation with an inner sphere of activity, addi- 
 tional to the sphere of action recognised in the sensori-motor 
 organism. 
 
 4. The joint action of the several muscles concerned provides 
 for the movement of the limb. The work done by the arms and 
 the legs is thus dependent proximately on muscular activity, 
 that again upon the impulse coming from the nerve fibre, 
 and that upon communication of impulse from the nerve cell. 
 Considering the movement of the limb as a fact, the key to the 
 fact is the activity of the motor cell ; observing the amount of 
 work done by the movement of the limb, the key to that is in 
 the muscular power ; taking account of the varying degrees of 
 energy which appear in successive actions of the limb, the key 
 to that may be found either in emotion, such as fear, or in 
 appetite, both of which belong to merely animal life ; or it may 
 be found in our own will or determination, guided by our 
 intellect, which contemplates a definite end to be gained by 
 the action. 
 
 Such is a summary of what is known as to the action of the 
 two forms of apparatus belonging to the nerve system. Allow- 
 ing for the difference between sensibility and muscular activity, 
 the nerve cell is the central feature in each case. Nerve cells 
 vary in size and form, and give off a variety of fibres differing 
 from the fibre which is the nerve proper. A nerve cell has a 
 clearly marked nucleus, and Avithin that a small central spot 
 known as the nucleolus. The cell is distinguished by spon- 
 taneous movement within, which is a characteristic of its life. 
 The cell has a property of excitability, providing for suscepti- 
 bility to impression, and activity in evolving nerve energy. 
 Molecular changes attend on such activity, and, as these 
 
202 THE RELA TIONS OF MIND AND BRAIN. ' [chap. 
 
 involve waste, there is in the cell power of assimilating nutri- 
 ment provided by the blood. 
 
 I pass now to speak of the ganglionic masses which make 
 up the' nerve centre. 
 
 Whatever diversity exists between the subdivisions of the 
 great central arrangement arises from the number and distri- 
 bution of the nerve fibres connected with particular parts. 
 Thus the several portions of cellular matter diffused within the 
 spinal marrow (if we may speak of separate portions) are, in a 
 manner, separate centres providing for reflex action through 
 means of the sensori-motor fibres united in them. The cere- 
 bellum has its own distinct gathering of fibres, and its functions 
 are to be found by reference to these. So in like manner it 
 is with the cerebrum. If, therefore, the question be raised, — 
 Why should the Cerebrum be regarded as the principal body 
 in the encephalon ? — the simplest and most direct answer is, — 
 Because it is the largest centre there, having the widest rela- 
 tions, and most commanding influence. Whatever remains to 
 be said as to Intelligence, this is the first and most conspicuous 
 feature. The greatest number of the sensory and motor nerves 
 take their course to the cerebrum. Eeflex activity may, 
 indeed, take place without any influence being carried higher 
 than the spinal cord. But there are direct lines of communica- 
 tion with the cerebrum. Taking the sensory division of these, 
 as they are gathered in the brain, we may, indeed, hesitate to 
 speak of such portion of the organ as the sensorium, lest the 
 word seem to imply a theory as to the mode in which impres- 
 sion at the periphery becomes known at the centre, yet is the 
 Cerebrum the great centre to which communications along the 
 sensory fibres are carried. And so is it the great centre from 
 which motor impulse proceeds. Many of the subordinate por- 
 tions of the central system are only minor centres for the 
 segregation or combination of sets of fibres, which nevertheless 
 have their true central terminus in the brain proper. The 
 combined anatomical and physiological results are therefore 
 accurately represented if we say that the Cerebrum is the grand 
 centre which provides for the sensibility of the physical frame 
 by receiving the impressions made on the sensitive surface, 
 and for motor activity by evolving the impulse which excites 
 muscular energy. 
 
vi.] ANATOMICAL AND PHYSIOLOGICAL RESULTS. 203 
 
 From the point at which the Cerebrum or Brain Proper 
 appears, all up the scale of animal life thereafter, the brain is 
 twofold in form, and the two hemispheres act so far as distinct 
 organs. From the fish upwards, there are two hemispheres in 
 the brain, lying in juxtaposition, each fundamentally distinct, 
 though closely and essentially related. As the brain proper 
 is in vital connection with every part of the body, each hemi- 
 sphere is connected distinctively with one side of the body. But 
 there is this notable fact, that the right is specially connected 
 with nerve fibres carrying impulses from or to the left side 
 of the body ; the left with fibres of the opposite side. The right 
 hemisphere thus provides for innervation of the left side of the 
 body ; the left hemisphere, of the right side. Each hemisphere 
 is so far a distinct organ, that each is encompassed with grey 
 matter, not only on the lateral surface, but on the base, and on 
 the surface where the two hemispheres are in contact, save 
 in some cases at a point of union, next to be considered. 
 
 In all mammals there is, about the middle of the cerebrum, a 
 transverse band of nerve fibres connecting the two hemispheres, 
 and known as the corpus callosum. In marsupials and some 
 other of the lower mammals, the corpus callosum is very small. 
 But as we ascend in the mammalian series, and more especially 
 when the brain becomes convoluted, the corpus callosum 
 increases in size, securing more effectual union of the two 
 hemispheres. In the human brain the corpus callosum is a 
 compact structure of considerable size, providing for intimate 
 relations between the two sides of the Cerebrum, by means 
 of its numerous transverse fibres. There is thus in man's 
 brain the most extensive provision for communication between 
 the hemispheres, and for co-operation of analogous portions 
 of the grey matter on the opposite sides. The duality of form 
 is very marked, but the compactness of union of the two sides 
 shows that the united mass acts as a single organ. This close 
 combination of the two hemispheres points to a higher degree 
 of control over a more largely developed muscular system, and 
 along with this a greater degree of sensibility over the entire 
 body, than are found in the lower animals. Considered sepa- 
 rately, each hemisphere is a centre for a distinct half of the 
 nerve system which spreads its ramifications over the body. 
 
204 THE RELA TIONS OF MIND AND BRAIN. [chap. 
 
 Considered unitedly, the two are compacted and harmonised 
 so as to constitute a unity, providing for the harmonising of 
 dual lines of sensibility, as in the case of the special senses, and 
 for uniform control over both sides of the body. 
 
 The evidence already adduced is concerned exclusively with 
 physical sensibility and motor activity. The teaching of anatomy 
 and physiology does not enable us to say what is the bearing 
 on mental action of this duality within unity, and unity with 
 duality. A distinct advance must be made into an entirely 
 new department of investigation before we can be in a position 
 to treat with any exactness of the facts of personal experience 
 which may be connected with these prominent features in the 
 human brain. Physiologists have, indeed, hazarded positive 
 statements on the subject ; but with this obvious disadvantage, 
 that the full evidence does not come within view from a purely 
 physiological standpoint. We must call in the aid of psy- 
 chology before we can treat successfully of the problem. Dr. 
 Terrier says, that " The brain, as an organ of motion and sensa- 
 tion, or presentative consciousness, is a single organ composed 
 of two halves ; the brain as an organ of ideation or re-presen- 
 tative consciousness, is a dual organ, each hemisphere complete 
 in itself. When one hemisphere is removed or destroyed by 
 disease, motion and sensation are abolished unilaterally, but 
 mental operations are still capable of being carried on in their 
 completeness through the agency of the one hemisphere. The 
 individual who is paralysed as to sensation and motion by 
 disease of the opposite side of the brain (say the right) is not 
 paralysed mentally, for he can still feel, and will, and think, 
 and intelligently comprehend with one hemisphere. If these 
 functions are not carried on with the same vigour as before, 
 they at least do not appear to suffer in respect of completeness." 1 
 
 This is an interesting and important passage, the full value 
 of which will appear somewhat later, but it involves conclu- 
 sions which are not established on physiological evidence. It 
 presents three orders of statement, including matters pro- 
 perly physiological, matters of common experience or observa- 
 tion, and matters properly psychological. Thus, it is matter 
 of common observation that a man paralysed on one side con- 
 1 Functions of the Brain, p. 257. 
 
vi.] ANATOMICAL AND PHYSIOLOGICAL RESULTS. 205 
 
 tinues to manifest intellectual power in every way equal to that 
 exercised when in full bodily vigour. A fine example of this we 
 had in Sir William Hamilton, Professor of mental philosophy 
 in Edinburgh, whose intellectual power was in nowise abated, 
 though motor paralysis of the right side was long established. 
 It is, next, quite certain, on physiological grounds, that disease 
 in the left hemisphere of the brain is the explanation of 
 paralysis down the right side of the body. But when Dr. Ferrier 
 advances a step further, he comes upon psychological ground, 
 and the statements are much more doubtful. The accuracy 
 of the distinction between " presentative " and " re-presenta- 
 tive " consciousness is open to question, because of the lack of 
 evidence to support it. Even the statement that the brain as 
 an organ of motion and sensation is an organ of presentative 
 consciousness needs to be somewhat guarded as the expression 
 of a physiological fact. That the brain is the organ of motion 
 and sensation, we have seen — evidence anatomical and physio- 
 logical amply establishing the fact ; but that the brain is at the 
 same time shown to be an organ of consciousness (in the sense 
 in which we speak of consciousness, and most commonly use 
 the term), we have as yet gathered no evidence to prove. Still 
 further removed from trustworthy evidence is the other state- 
 ment that the brain is " an organ of ideation," and as such 
 an organ of " re-presentative consciousness." It is matter of 
 common experience that man " can feel, and will, and think," 
 and if all these are included under " ideation," we know that 
 all these exercises are performed when both sides of the brain 
 are in a healthy state; that they continue to be performed 
 when one hemisphere is diseased and the other healthy ; and 
 that when both hemispheres are diseased life speedily ter- 
 minates. But we are not in possession of evidence to prove 
 that the brain is a single organ, as an organ of sensation and 
 motion, but a dual organ as an organ of " ideation." Nor have 
 we proof that " ideation " is a re-presentation of what was pre- 
 viously presented in consciousness by sensori-motor activity. 
 From the analogy of physiological law, however, it may reason- 
 ably be doubted whether one hemisphere of the brain is 
 adequate for the whole of " ideation," while that hemisphere 
 suffices for only one half of the motor activity and sensation, — 
 
206 THE RELA TIONS OF MIND AND BRAIN, [chap. 
 
 that one hemisphere can re-present what the two hemispheres 
 are required to present. This hypothesis implies that " idea- 
 tion" is a simpler exercise, which may be performed with 
 less brain power than motor activity 'and sensation. Or, to 
 put it in another form, if " ideation " be a function of brain, 
 one half of the brain does as much as the whole. Such a 
 hypothesis is difficult to accept ; and in lack of positive evi- 
 dence, we must keep by the analogy of physiological law, and 
 affirm that a half brain can do only half work, instead of 
 assenting to the position that the brain is in one sense " a 
 single organ composed of two halves," and in another " a dual 
 organ, each hemisphere complete in itself." 
 
 Taking now another step in our summary of results of com- 
 parative physiology of brain, we reach the position that the 
 brains most elaborate in convolution are associated with the 
 most highly developed muscular system. After a beginning has 
 been made with the more simple convolutions in the brains of 
 the cat and dog, we pass, in course of observation, to beautifully 
 folded convolutions, as these appear in the examples now to be 
 mentioned. The brains here included are those of the horse, 
 ape, elephant, and whale, taken along with the human brain. 
 There is the brain of the horse, whose muscular power has come 
 to afford the standard by which we estimate the comparative 
 power of the steam-engine. There is the brain of the anthropoid 
 ape, whose muscular power is such that the strength of three or 
 four men is required to master a very young specimen, and when 
 full grown a single stroke of its arm causes certain death to a 
 man. There is the brain of the elephant, whose size is such 
 that at its maximum height it stands between nine and ten feet 
 at the shoulder; its limbs of such proportions that the cir- 
 cumference of its foot is about one-half the animal's height, 
 while it is capable of carrying with ease on its back one ton 
 weight. And there is the brain of the whale, so wonderfully 
 minute in the windings of the convolutions as to be quite 
 singular in this respect ; an animal, the mere stroke of whose 
 tail can endanger a large ship. 
 
 In confirmation of the conclusion that elaboration of brain is 
 connected with development of the muscular system, we must 
 take the results of electric stimulation. By direct experiment 
 
vi.] ANATOMICAL AND PHYSIOLOGICAL RESULTS. 207 
 
 it has been shown that electric stimulation of the cortex of the 
 cerebrum is sufficient to induce movement of the limbs and of 
 the muscles, of the face. When the general result is contem- 
 plated, it appears that the greater part of the brain is included 
 within the area thus appropriated, the parts not embraced being 
 the occipital lobe, and the larger portion of the frontal. When, 
 in addition to these motor centres, with some few correlated 
 sensory centres which have been identified, we add the sensory 
 tracts whose central terminus has not been fixed under these 
 experiments, and the motor centres for the whole range of ex- 
 pression peculiar to the human countenance, and for the 
 varieties in the form of articulation, we are led to the conclu- 
 sion that, at least, the great bulk of the brain is connected with 
 the sensory and motor activity of the nerve system. 
 
 In some cases, including among the numbei* the rat, rabbit, 
 cat, dog, and horse, the olfactory tract is so prominent as to 
 indicate that the sense of smell has a governing influence in the 
 natural or untrained life of the animal. Wherever the olfactory 
 bulb no longer projects beyond the front of the cerebrum, its 
 withdrawal from prominence seems to imply that a relatively 
 higher place in the government of the life has been assigned 
 to sight and touch. 
 
 Further, it appears that more intricate arrangement and sub- 
 division of the brain is connected with more detailed arrange- 
 ment of the muscular system, in contrast with mere mass of 
 muscle. The brain most nearly allied to man's is that of the 
 anthropoid apes. With the resemblance of brain structure 
 there is connected resemblance of bodily conformation, of mus- 
 cular appliances for semi-erect movement, and of fingers on the 
 extremities ; and this last feature is carried even to a more de- 
 tailed extent in the ape on account of its possession of feet, 
 which, at the same time, fulfil the functions of hands. With 
 hands and feet formed as already described, the apes occupy 
 a distinct position in the animal kingdom. If we take by con- 
 trast the other animals possessed of a highly organised brain, 
 the difference as to the extremities is quite striking. The dog, 
 the horse, the elephant, and the whale are the animals most 
 noted for brain formation, and these all differ completely from 
 the ape in the comparative simplicity of the structure of the 
 
zo8 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 extremities, and the comparatively restricted use which can be 
 made of them. If, then, the brains of the apes be more like to 
 man's brain than the brains of other highly developed animals, 
 some considerable amount of nerve and brain power in the apes 
 goes to the increased tactile exercise which is characteristic of 
 these animals. Further, if the brain of the monkey be like an 
 outline map of man's brain, and the anthropoid ape's brain 
 like a better filled-in map of the same, this contrast between 
 the brain of the smaller and that of the larger animal gives 
 additional support to the view that advance in brain structure 
 is accounted for by advance in muscular development. Again, 
 if the brain of the ape be that most allied to man's brain, the 
 contrast between the ape and man is great in respect of sensi- 
 bility. The combination, minuteness, and fineness of sensory 
 nerves are points in which the superiority of man over the ape 
 is apparent. This implies superiority of brain, as well as of 
 nerve ; accordingly this carries at least in part an explanation 
 of the diversity of brain in the two cases. The nerves of the 
 ape are larger ; the nerves of man are finer, and much more 
 minute. Accordingly, the work of innervation to be done by 
 the human brain is much more detailed, thus requiring a fuller 
 and more elaborately organised nerve centre. 
 
 The regions in which the superiority of the human brain 
 appears are the frontal and parieto-occipital lobes. The frontal 
 lobes specially predominate over those in the brains of other 
 mammals. At the same time, the anthropoid ape's brain is fuller 
 than the monkey's in both regions. It will follow that, in what- 
 ever the ape is thereby superior to the monkey, man is superior 
 to the ape. But this superiority is not in " intelligence ;" nor in 
 a quicker and more discriminating use of the special senses. In 
 the former the monkey is at least equal to the ape ; in the latter, 
 decidedly superior. 1 Thus far the results of comparative ana- 
 tomy and physiology point to a superior and better governed 
 muscular system, as the chief explanation of superiority of 
 brain. That superiority of intelligence in man, which is con- 
 fessedly so vast as to place a " great gulf" between the lowest 
 of the human race and the fully developed ape, has a very 
 limited area of brain to which its varied forms of activity can 
 1 Functions of the Brain, p. 170. 
 
VI.] ANATOMICAL AND PHYSIOLOGICAL RESULTS. 209 
 
 be assigned. The superiority of the frontal and parieto- 
 occipital lobes in man is great; but it seems required to 
 account for the activity of a greatly superior muscular and 
 sensory apparatus. 
 
 In view of the outstanding problem concerning Intelligence, 
 two results of electric excitation of the brain require considera- 
 tion. These are, failure in the attempt at stimulation of the 
 frontal and occipital lobes, and in other parts rapid restoration 
 of functional activity after complete removal of the portion 
 of cellular tissue previously identified as the normal centre 
 for that activity. Large supplies of sensory nerves go to the 
 frontal and occipital lobes, but chiefly to the latter. It may 
 be that part of the explanation of absence of apparent result 
 under the electrodes is the presence of purely sensory nerves, 
 or the predominance of such nerves. Excitation of such nerves 
 must be at the periphery. This form of explanation will apply 
 more to the occipital than to the frontal lobe, the latter still 
 demanding some further consideration. It is admitted that 
 both sensory and motor nerves go to the frontal lobe, but more 
 of the motor than of the sensory. This latter fact increases 
 seriously the perplexity occasioned by absence of response. 
 If the frontal be admitted to have distinctive work, as com- 
 pared with the occipital, that work must be indicated by this 
 predominance of motor nerves, showing a governing power 
 rather than a receptive tendency. There is sufficient warrant 
 for maintaining that a central controlling power belongs to the 
 frontal lobe in all convoluted brains. Dr. Ferrier's observa- 
 tions on monkeys from which the frontal lobes had been 
 removed involve these points, that the animals " retained their 
 appetites and instincts," their sensory faculties "remained 
 unimpaired," and their " powers of voluntary motion." " Though 
 it might seem to one who had not compared their present with 
 their past, fairly up to the average of monkey intelligence," 
 "they remained apathetic, or dull, or dozed off to sleep." 1 
 Their deficiency seemed to be loss of concentrated observation. 
 That the function of the cells in the frontal lobe differs 
 essentially from the function assigned to the cells in the other 
 lobes, there is no evidence to prove. The possibility of some 
 
 1 Functions, p. 231. 
 
210 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 difference may be left an open question, but this is the utmost 
 that can be granted. If power of intelligence be lodged some- 
 where, there is nothing, either in the outer formation of the 
 brain, or in its internal structure, to indicate a distinct centre 
 for such a power. The utmost that can be said is, that a measure 
 of concentrating power for the organ as a whole, and thereby 
 for the nerve system in all its ramifications, belongs to the 
 frontal lobe. As the cerebellum is the centre which provides 
 for equilibrium in locomotion, and the cerebrum, as a whole, 
 is the governing centre for the entire nerve system, so is the 
 frontal region of the cerebrum the governing centre for the 
 organ itself. In some way, not at all explained, the general 
 centre of control seems to belong to the frontal region. That 
 in human life mental phenomena, including the ordinary 
 forms of intellectual action, are connected with the central 
 government of the nerve system, is admitted as beyond dis- 
 pute ; but that these phenomena are the product of brain acti- 
 vity, there is no scientific evidence to show. Throughout the 
 whole course of the preceding inquiry, nothing has been ascer- 
 tained affecting the nature and functions of the brain to account 
 for the most common of them. Any theory which would include 
 " intellectual " phenomena as functions of brain is exposed to 
 peculiar difficulties, because of the bearing such a theory must 
 have on general interpretation of the nerve centre. To maintain 
 either that a limited portion of the grey matter, defined by 
 certain boundaries, has a function of intelligence, or that the 
 whole of the grey matter has this function, is extremely difficult 
 in view of the facts. I have endeavoured to present in detail 
 the evidence as to structure and function of brain and nerve, 
 and there does not seem to be any portion of that evidence 
 pointing to the conclusion that, to the sensory and motor 
 functions, there fall to be added intellectual functions. There 
 is still, indeed, a wide region of inquiry before us ; but it opens 
 to view as new territory ; and at this stage it seems our only 
 possible conclusion, that anatomical and physiological investi- 
 gations as to brain and nerve, so far as they have yet been 
 carried, afford no explanation of our most ordinary intellectual 
 exercises. 
 
vii.] EXPERIENCE AS CONNECTED WITH SENSATION. 
 
 CHAPTER VII. 
 
 PERSONAL EXPEEIENCE AS CONNECTED WITH SENSATION. 
 
 An additional set of facts must now be taken into account. 
 These are facts which do not come within the scope of anato- 
 mical and physiological research, yet are essentially connected 
 with the present inquiry. I refer to the facts of our experi- 
 ence. There is a relation between the action of the nerve 
 fibres and cells, both sensory and motor, and an experience of 
 our own, properly designated personal experience. How much 
 is involved in the expression " personal experience " may after- 
 wards appear ; what is meanwhile to engage attention is the 
 relation of two distinct sets, of facts. When my hand is laid 
 now on one surface and again on another, nerve sensibility is 
 acted upon in each case, but besides this I am conscious of 
 a series of sensations, and I distinguish between contact with 
 a rough or smooth, a soft or hard surface. And so, taking 
 account of the phenomena of personal activity, or the experi- 
 ence connected with physical exercise, I am conscious of 
 willing to move one or other of my limbs, and I observe by 
 sight movement of my hand or foot accordingly. An influence 
 is transmitted along the motor nerves, and I am conscious of 
 determining the action. These two classes of facts, know- 
 ledge of various sensations, and knowledge of efforts put forth 
 by myself, together belong to that set of facts which makes up 
 " personal experience." Such facts are characteristic of human 
 life. The question to be specially considered is, How far are 
 such facts accounted for by the recognised functions of nerve 
 and brain ? 
 
 In order to present clearly the relation of the facts considered 
 in previous chapters with those now to be brought under 
 review, it should be remarked that consciousness does not 
 involve any knowledge of brain action. " Consciousness does 
 
212 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 not even tell us that we have a brain." 1 Brain action is not 
 matter of experience with us. Nor have we any direct know- 
 ledge of what is involved in the action of the nerve fibres. 
 The person who is well aware of the sensitiveness of nose, 
 eyes, and ears is not thereby made acquainted with the struc- 
 tural arrangements by which such sensitiveness is induced. 
 The person who freely uses his limbs has not attained to this 
 freedom of action by any knowledge of the mechanical contriv- 
 ances by means of which the movements are effected. We begin 
 in early life the use of sensibility and motor energy with as little 
 knowledge of the conditions of their exercise as any of the 
 lower animals possess. Only by the slow and laborious methods 
 of anatomical and physiological research has the human race 
 become aware of the physical conditions of sensory impressions 
 and motor activity. But the utmost advance of anatomical 
 and physiological science does not bring the investigations 
 within the region of consciousness. On the other hand, how- 
 ever carefully we study our consciousness, we do not thereby 
 attain to any knowledge of the nerve system. This severance 
 of the two departments of inquiry must impress all who study 
 the relations of brain and mind. Professor Tyndall has said — 
 " The passage from the physics of the brain to the correspond- 
 ing facts of consciousness is unthinkable. Granted that a 
 definite thought and a definite molecular action in the brain 
 occur simultaneously, we do not possess the intellectual organ, 
 nor apparently any rudiment of the organ, which would enable 
 us to pass, by a process of reasoning, from the one to the other. 
 They appear together, but we do not know why. Were our 
 minds and senses so expanded, strengthened, and illuminated 
 as to enable us to see and feel the very molecules of the brain ; 
 were we capable of following all their motions, all their group- 
 ings, all their electric discharges, if such there be ; and were 
 we intimately acquainted with the corresponding states of 
 thought and feeling, we should be as far as ever from the solu- 
 tion of the problem, How are these physical processes connected 
 with the facts of consciousness?" 2 The facts are clearly dis- 
 tinguished from each other, but how the one set of facts is 
 
 1 Maudsley, Physiology of Mind, p. 21. 
 
 2 Fragments of Science, p. 121. 
 
vii.] EXPERIENCE AS CONNECTED WITH SENSATION. 213 
 
 connected with the other is not matter of perception, and 
 cannot be directly ascertained. We must now, therefore, make 
 a complete change, of position, passing over to the facts of con- 
 sciousness, which are to he studied as carefully as the facts 
 bearing on the structure and functions of nerve and brain. 
 This new order of facts may in the earlier stage of investigation 
 be taken in two divisions, the one correlated with the action of 
 the sensory apparatus, the other with the action of the motor 
 apparatus. I begin with the facts of experience dependent on 
 nerve sensibility. 
 
 One of the most common and simple facts in personal 
 experience is the relation between touch and sensation. Ex- 
 perience makes certain to us a relation between sensibility 
 on the surface of the body and a form of knowledge we desig- 
 nate Sensation. Anatomy and physiology intervene to explain 
 the appliances for maintaining surface excitability and com- 
 munication with the nerve centre. Psychology points out the 
 essential features of sensation as the lowest type of human 
 knowledge, and classifies the various phases of experience 
 coming under this designation. But, quite apart from science 
 and philosophy, ordinary human experience makes palpable 
 the relation between surface sensibility and knowledge depen- 
 dent on such sensibility. A person lays his finger on a sheet 
 of note-paper, thereafter on the table-cover, and next on the 
 ink-bottle; each successive instance of contact gives him a 
 distinct item of experience. A repetition of the same acts 
 gives the same results. This person steps out of doors, he feels 
 a gentle breeze play upon his face, he strikes his foot against a 
 stone which lies on the path, he is jostled by a person hurrying 
 along in an opposite direction: there is for him a distinct 
 experience connected with each example of contact. So con- 
 stant is this relation that we are prone to identify sensibility 
 and sensation, and in doing this we speak rather of our sensa- 
 tion than of the sensibility of our finger or face, foot or elbow. 
 As Mr. Lewes has said — " Do what we will, we cannot alto- 
 gether divest sensibility of its psychological connotations, 
 cannot help interpreting it in terms of Consciousness." 1 Our 
 experience includes sensations; observations by sight afford 
 1 The Physical Basis of Mind, p. 188. 
 
214 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 contributory evidence. The observation of external contact 
 and the internal sensation are associated as correlated facts. 
 The observation of the one and feeling of the other belong 
 to personal experience, and the evidence of the causal rela- 
 tion of the contact and the feeling is made clear by repetition 
 of the experiment. It must not be supposed that in this 
 case the ultimate test is sight. It is in reality some deeper 
 power of comparison belonging to us, for a blind man can 
 reach the results as accurately as a man possessed of sight. 
 When a person using the organ of vision experiments as to 
 the sensibility of the finger when brought into contact with 
 a variety of surfaces, there are four essential features in each 
 experiment. There is, first, voluntary application of the finger 
 to the surface ; second, observation of contact, which may be 
 dispensed with, as in the case of the blind ; third, sensation or 
 feeling ; fourth, recognition of the relation of the act of touch 
 to the feeling. 
 
 This brief introductory statement may suffice to indicate the 
 nature of the facts to be considered, the wide range of problems 
 raised by the attempt to explain them, and I venture to add, 
 the impossibility of physiological science presenting an ade- 
 quate answer to these problems. Physiology deals with the 
 functions of those organs which anatomy has brought to light. 
 In doing so it has established sensibility of the terminal organ, 
 integrity of communication with the centre, and reception of 
 impulse by the sensory cell. We must now connect these 
 things with the facts of our experience. A philosophy of ex- 
 perience must follow a physiology of the sensory nerves, and 
 the two together must make up our philosophy of human 
 sensations. 
 
 It is obvious, as Mr. J. S. Mill has said, 1 that we cannot go 
 back in personal experience to the rise of self-consciousness, 
 with the view of constructing a history of the development of 
 our knowledge. Nor will observation of the dawn of intelli- 
 gence in the life of a child supply what is required. There is 
 but one method open, analysis of present experience, in order 
 to discover its essential elements. A succession of sensations 
 is easily recognised in our experience, and easily isolated for 
 
 1 Examination of Hamilton's Philosophy, 3d ed. p. 17 1. 
 
vn.] EXPERIENCE AS CONNECTED WITH SENSATION. 215 
 
 examination. Such experiments as those already described, 
 involving the simple use of the sense of touch, supply the 
 materials needful for the philosophic process. The sensory 
 nerve, wherever found, fulfils the same function. Diversity of 
 experience connected with the action of sensory nerves de- 
 pends on the position of the fibrei or on the terminal arrange- 
 ments at the periphery, or upon the external object which 
 affects it. Our present problem includes all these considera- 
 tions, along with everything additional belonging to experi- 
 ence consequent on sensory activity. 
 
 The examples already enumerated will suffice for illustration. 
 A person touches with the forefinger a sheet of note-paper, a 
 table-cloth, and an ink-bottle. Passing to the open air, the 
 breeze plays on his face, he strikes his foot against a stone, and 
 is jostled by a passer-by. The facts brought under notice are 
 these : simple sensation, succession of sensations, difference 
 of sensations, discrimination of sensations, discrimination of 
 things, or knowledge of external reality by means of sensation. 
 Each sensation is a distinct fact of experience dependent on a 
 single separate action or vibration of the nerve fibre. The 
 fibre must have accomplished its functional action in one case 
 before it is capable of performing another like action. If we 
 try to hurry the actions of the fibre, we lose distinctness. There 
 is thus entire separateness of action in the organism ; the union 
 is in our experience, and nowhere else. The successive sensa- 
 tions, united in experience, are, however, distinguished by us, 
 and that not merely as facts following each other in a certain 
 order, but as forms of experience differing from each other in 
 nature. Nay more, not only are the feelings distinguished, 
 but so also are the things or objects by contact with which 
 the sensations arise. The nerve movements are not dis- 
 tinguished by us, because they are not experienced. But all 
 these other features belong to the experience described by 
 simple enumeration of the six different sensations involved 
 in the experiment now under consideration. A philosophy of 
 human sensations must then be a philosophy of all these 
 elements of experience. 
 
 A single sensation, such as that which follows the touching 
 of a sheet of note-paper, is a distinct experience. It is so far 
 
216 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 accounted for by what physiology teaches, but it is explained 
 thus only in part. In so far as there is sensibility at the tip 
 of the finger, conductivity along the nerve fibre, and recep- 
 tivity or consequent molecular action in the nerve cell, we 
 have exact and important information, but the explanation is 
 incomplete, and is not a philosophy of our sensation. What 
 the receptivity of the sensory cell involves has not yet been 
 made out, but may come to be ascertained. It is admitted, 
 however, that some molecular change takes place as the con- 
 sequence of each distinct act of the nerve fibre, whether the 
 change be represented as a movement, vibration, or shock occa- 
 sioned in the sensory cell. On the other hand, the admission 
 of such molecular change does not help towards a philosophy 
 of sensation, for it is admitted that molecular change must in 
 like manner occur in the motor cell, when there is liberation 
 or discharge of nerve energy along an outgoing or motor nerve. 
 Change in the substance of the brain is granted in both cases 
 on the single or common ground that movement or action of 
 the substance must involve change. Whether the action be 
 sensory or motor does not affect the common law of brain 
 activity. This being so, the admission of molecular change in 
 the sensory cell as the result of the activity of a sensory nerve, 
 gives as yet no help towards the explanation of sensation. At 
 this point we reach the close of the physiological contribution. 
 All that we know of nerve substance, whether fibre or cell, fails 
 to explain the simplest and most familiar fact in our experi- 
 ence. We have exhausted the known properties of nerve 
 substance, and we are precluded from accepting Professor 
 Bain's theory, of " one substance, with two sets of properties -," 1 
 and every similar theory which depends wholly on sensory 
 apparatus. 
 
 What has yet to be explained is our experience. What has 
 been explained is that of which we have no experience, con- 
 ductivity of nerve fibre, and receptivity at the sensory cell, 
 
 action within our organism, but beyond our experience. We 
 still need to account for what is familiar to every man, and is the 
 simplest element in human knowledge, — Sensation, — the sensa- 
 tion consequent on touching a sheet of note-paper. And this, 
 
 1 Mind and Body, p. 196. 
 
vii.] EXPERIENCE AS CONNECTED WITH SENSATION. 2 I7 
 
 it must be noticed, is something quite different from a merely- 
 agreeable or disagreeable state consequent on the sentiency 
 of animal existence. It is, for example, quite distinct from the 
 comfortable condition of the child whose hunger has been 
 appeased, and who is content to sit still in a quiescent state, 
 or the satisfaction of the animal which lies basking in the 
 sunshine. To touch a piece of note-paper is certainly not 
 disagreeable, but neither can it be spoken of as agreeable in a 
 sense analogous to that intended when we speak of any 
 physical satisfaction. When referring to the result of tactile 
 impression, we are not speaking of that which may come within 
 the category of the pleasurable, or of the painful, but of that 
 which may more properly be described as the informing, some- 
 thing concerned with the sensible or knowable, as we intend 
 when we speak of using our Senses. There is sensibility in 
 both cases, but the contrast is this : in the one case we have 
 experience of the agreeable, in the other of the sensible or 
 knowable ; we know that we feel, and we know that we know. 
 The thing waiting explanation may be expressed thus : In 
 touching a piece of paper we are conscious of a distinct ex- 
 perience, beginning and ending within a very few moments, — 
 little more than momentary, and which we call a sensation. 
 This implies that we know this experience as our own, and 
 report it in the terms here adopted as a distinct fact, rather 
 than a continuous state, agreeable or otherwise. Or to put it 
 from the point of view afforded by our own personality, for 
 that is somehow involved in our experience, one may say, 
 I know myself as experiencing this particular impression which 
 has arisen on account of my use of the tactile sense. And 
 here we must keep in view the most important contribution 
 to our study afforded by the facts of reflex action (p. 80). 
 There is an action of the sensory apparatus without sensation. 
 There is excitation at the periphery, activity of the sensory 
 nerve, and receptivity at the nerve cell without any sensation, 
 the result being an action. There is, besides, something 
 voluntary in the use made of the sense of touch in the experi- 
 ment before us, but that important feature may be held in 
 reserve for a later stage of this inquiry. We are not only 
 sentient, but also cognisant of the fact. This is the contrast 
 
218 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 between the child whose appetite is satisfied, whose body has 
 a sufficient degree of warmth, and who lies in placid content- 
 ment just where it is laid ; and the man who uses a special 
 sense, such as Touch. What is meant by the statement that 
 the touch of paper occasions a particular sensation is, that I 
 know myself as experiencing the sensation which a single act 
 of tactile impression has produced. What Physiology has done 
 is to account for tactile impression, — a sensibility belonging to 
 man's organism. What Physiology does not accomplish is to 
 account for that knowledge of himself existing in a particular 
 state, which is for an intelligent being the most simple and 
 ordinary experience accompanying tactile impression. Psy- 
 chology begins with this, as the simplest and the primary fact, 
 knowledge of self as experiencing a particular sensation. Any- 
 thing in experience more simple than this we never have. 
 
 Next, taking account of a succession . of sensations, forming 
 a continuity of experience, Psychology advances a step by 
 simple observation of the fact that human experience involves 
 knowledge of Self as having varied experience, and know- 
 ledge of the different sensations as equally belonging to Self. 
 Professor Bain has admirably shown that difference is in 
 some sense the very condition of our knowledge. " The 
 necessity of change in order to our being conscious, is the 
 groundwork of thought, intellect or knowledge, as well as of 
 feeling." 1 Thus " discrimination is the very beginning of our 
 intellectual life." 2 Sensation is a given amount of knowledge, 
 but each sensation is known to us as a new experience. And 
 in saying this, we say that in each experience of sensation 
 there is more than sensation, — there is knowledge that the 
 particular sensation arising at the moment is distinct from 
 another previously experienced. There is distinction, then, in 
 in respect of time, the one coming after the other. There is 
 besides distinctness in respect of completeness of each fact, for 
 each has its beginning and end, as with three distinct acts of 
 touch. Physiological conditions imply the separateness of each 
 vibration of the sensory nerve as a distinct effect from each 
 act of contact. And in strict accordance with these, con- 
 sciousness recognises distinctness of event. Thus, sensation 
 1 Mind and Body, p. 81. 2 Hid. p. 83. 
 
vil.] EXPERIENCE AS CONNECTED WITH SENSATION. 219 
 
 as a fact in our experience implies consciousness, and con- 
 sciousness of the distinctness of a sensation implies recog- 
 nised distinction of the present sensation from the preceding. 
 To say this is to indicate that sensation and consciousness are 
 not identical, — that consciousness has the particular sensa- 
 tion as its object, — and that consciousness involves a wider and 
 higher exercise of intelligence ; for while sensation is only a 
 particular and single experience, in accordance with the single- 
 ness of nerve action on which it depends, consciousness dis- 
 tinguishes one sensation from another, — an exercise for which 
 we have found no provision in nerve action. By vital union 
 with the nerve centre, the nerve fibre is kept in constant 
 sensibility ; each distinct impact on the periphery is followed 
 by a distinct exercise of conductivity and receptivity. There 
 must be a separate act of contact for exercise of the conduc- 
 tivity of the nerve tract ; and there must be a definite mole- 
 cular change at the centre where the shock is delivered. But 
 here physiological teaching comes to an end. The sensory 
 apparatus provides for diversity of result; but not for com- 
 parison of the differences. The law of nerve action implies 
 the contrary, the cessation of one action as the condition of 
 another. Even if physiological hypothesis were ventured in 
 the form of a suggestion that there may be in the sensory cell 
 a register of the shock delivered there, this would not help us 
 towards an explanation of the facts of consciousness. Even if 
 there were such a register, and the registration were made on a 
 sensitive surface, and were permanent, this would not meet the 
 requirements of the case. A register contains the materials for 
 comparison, but does not institute comparisons. The facts 
 carry us quite beyond mechanical contrivance, inasmuch as 
 one thing not only follows another, but one thing is compared 
 with another ; that is, there is not only one thing distinct 
 from another, but one thing is distinguished from another. 
 
 Eestricting attention now to consciousness, there is recog- 
 nition of the distinction between a present and a past sensa- 
 tion. The psychological conditions of human sensation are 
 knowledge of an experience as belonging to self, and know- 
 ledge of the distinction between the present and the preceding 
 sensation. How far such power of discrimination may be con- 
 
220 THE RELA TIONS OF MIND AND BRAIN. [chap. 
 
 nected with the sensibility of the lower animals, it is impossible 
 to say; but human sensation involves discrimination. Ex- 
 perience in its lowest phase implies knowledge of a difference. 
 Mr. James Mill, Mr. J. S. Mill, and Professor Bain have all 
 favoured the view that sensation and consciousness are not 
 distinct, or at least are not uniformly and of necessity dis- 
 tinguished by us. But the untenableness of such a position is 
 apparent if it be true, as is granted, that " discrimination is 
 the very beginning of our intellectual life." 1 
 
 We must, then, notice how much we are leaving behind to 
 which importance attaches as essential to sensation, though 
 contributing nothing to explain the discrimination involved. 
 " Intercourse of the organism with its environment" 2 is taken 
 into account, but affords no explanation, besides leaving a 
 fresh problem on hand as to voluntary intercourse through 
 tactile sense. "The motion and sensation of cells, and of 
 organism built up of cells," 8 are made account of as affording 
 a condition essential for the experience which follows touch of 
 a piece of note-paper, but though involved in sensory activity 
 they do nothing to explain discrimination. The simple experi- 
 ences of the agreeable and the disagreeable — what Haeckel 
 speaks of as "the simple sensations of delight and aversion 
 (Lust und Unlust)" 4 — do not play any important part in this 
 experience dependent on tactile impression, and they show us 
 nothing as to the discrimination which is implied in the suc- 
 cession of sensations. All these being granted, they do not 
 render any assistance towards the explanation required. 
 
 The outstanding fact remains — human experience implies 
 discrimination. This is not accounted for by the sensibility of 
 nerve fibre, nor by the sensation which results from the exer- 
 cise of such sensibility. It clearly involves a power higher 
 than both. Tactile impression implies touch, and a new im- 
 pression a new touch ; sensation implies impression, and a 
 new sensation a new impression ; but comparison of sensations 
 
 1 I have elsewhere discussed this question at length, Handbook of Moral 
 Philosophy, pp. 100-108. 
 
 2 Herbert Spencer's First Principles, p. 16. 
 
 3 Haeckel's Die heutige Enlioiclcelungskhre im VerhaUnkse ztir Gesammt- 
 wissenschaft, p. 14. 4 /j;^, p. 14, 
 
vii.] EXPERIENCE AS CONNECTED WITH SENSATION. 221 
 
 implies a knowledge of a sensation which has passed away, 
 and a knowledge of a sensation which still exists, and an 
 intelligent discrimination between the two as completely dis- 
 tinct realities. The known laws of train action do not provide 
 for this; they imply that the nerve system is not equal to such 
 work. It is a law of nerve action that the nerve fihre must 
 be clear of one impression before it can be made the vehicle 
 of another. That is, singleness of action is a law of exercise 
 for the sensory nerve. Successive touches of the note-paper, 
 table-cloth, and ink-bottle give successive vibrations and 
 distinct sensations, but an attempt to combine all three im- 
 pressions in one would end in confusion, not in discrimination. 
 Accordingly, the discrimination which takes place is the dis- 
 tinguishing of sensations as separate and successive events, 
 each one of which ends before the other begins. Further, it is 
 a law of nerve action that any sensory nerve is thrown into 
 vibration by contact ; accordingly any number of unemployed 
 fibres may be brought into use at the same time. If at the 
 same moment we use two fingers, rubbing the tip of one on 
 the leather of the desk, and the tip of the other on the polished 
 wood, two distinct impressions are made, two distinct sensa- 
 tions are experienced at the same time, but each fibre does its 
 own work quite apart, and each sensation is a perfectly distinct 
 event. The separateness of the two sensations is the simple 
 result of the distinction of the nerve fibres, but the discrimina- 
 tion of the two as rougher and smoother is not secured by 
 the action of the fibres. Action of a sensory nerve results 
 from impulse, whatever be the nature of surface which com- 
 municates it ; marking the differences of sensations, implies 
 practice in comparison and large use of memory. Next, let 
 the whole ten fingers be moved over the same surface at the 
 same moment, and we fail to distinguish ten distinct sensations. 
 The failure in discrimination does not occur because there are 
 not ten distinct impressions, with ten distinct molecular changes 
 in the brain, and ten distinct sensations, but because we have 
 not discriminating power enough to deal with so many. In 
 this way it happens that multitudes of impressions are made 
 on the sensory nerves which are never noticed by us. The 
 failure in this case to keep the distinction sharply confirms 
 
222 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 the view that the discriminating power is quite distinct from 
 that which determines the existence of the sensation. The 
 nerve fibres can do more work than the discriminating power 
 at our command can interpret, Thus the intricacy of the 
 ramifications of the sensory system confirms the conclusion 
 here maintained. 
 
 The general result becomes obvious. If I experience a sen- 
 sation, I experience it as mine, and in doing so distinguish it 
 from that which preceded it. This implies these three things : 
 knowledge of self as influenced in some way from without, 
 recalling something which has passed away, and comparing 
 the present state with a past. So far as here appears, self- 
 knowledge, as illustrated by the lowest phase of experience, 
 Sensation, is knowledge of Self as possessing a power superior to 
 sensation, that is, a discriminating power, which is Intelligence. 
 
 Tbis conclusion is strongly confirmed when we take account 
 of the additional fact, that by means of our sensations vie dis- 
 tinguish the surfaces brought into contact with the tips of the 
 fingers. When we distinguish the smooth surface of the paper 
 from the rougher and softer surface of the woollen table-cloth'; 
 and when we proceed to still nicer discrimination, distinguish- 
 ing between the smoothness of the paper and the smoothness 
 of the glass, there is a clear advance in the exercise of dis- 
 criminating power. It is the advance from what is properly 
 named Sensation, to what we more properly designate Percep- 
 tion} By aid of auxiliary appliances, that is, by voluntary 
 use of powers at our command, which may include several of 
 the special senses, we attain to knowledge of qualities in the 
 objects, or distinguishing characteristics of the objects coming 
 into contact with the sensory nerves. The nerve system is 
 such as to admit of its being readily put to such exercise ; but 
 it is not in itself such as to explain the exercise. A series of, 
 sensations provides the materials from which we gather our 
 knowledge, but neither the sensations themselves, nor the imr 
 pressions by which they are originated, can account for our 
 knowledge. Here also, as in the case of sensation proper, 
 comparison and memory are at work, and both have enlarged 
 
 1 See Hamilton's edition of the Works of Dr. Thomas Reid, p. 876, — 
 Hamilton's Dissertation, — Note D* — Perception proper, and Sensation proper. 
 
yn.] EXPERIENCE AS CONNECTED WITH SENSATION. 223 
 
 exercise, while a voluntary use of several instruments of know- 
 ledge shows an intelligent nature at work for intelligent ends. 
 There is a repetition of touch applied to the same surface, to 
 establish the identity of the sensation ; touch is next applied in 
 succession to the different surfaces, to establish the exact con- 
 trast of sensations ; the eye also is brought to bear on the several 
 surfaces, to give increased definiteness to the contrast between 
 the objects. Discrimination is carried still further, even to 
 the distinguishing of two phases of sensation dependent on 
 a single act of touch, as when both " smooth " and " cold " are 
 recognised by a single touch of the ink-bottle. Thus again is 
 a new series of contrasts instituted, inasmuch as the sense of 
 cold is found to be induced by touch of the ink-bottle in a 
 greater degree than by touch of the note-paper, while it is not 
 recognised by touch of the woollen surface. By acts of dis- 
 crimination extended in this way, we come to know a set of 
 qualities belonging to one object, and a distinct set belonging 
 to another, and so we reach Conceptions of objects, by the aid 
 of which we can discriminate one individual of a class or 
 species from another, as, for example, different qualities of 
 note-paper, differing from each other in size, colour, and the 
 preparation of the surface. 
 
 Now, all this work, which is quite familiar to us, and which 
 can be done by a very young child, being indeed the simplest 
 form of instruction for a child, is work to which brain and 
 nerve contribute, but which they do not accomplish. The in- 
 sufficiency of brain and nerve to perform such work is really 
 involved in the statement of the laws of brain action, and the 
 functions identified as belonging to fibres and cells. As to the 
 nerve fibres there is scarce room for debate. The sensibility 
 of the peripheral extremity of the fibre is one, and is acted 
 upon in precisely the same manner by any surface which 
 comes into contact with it. The conductivity of the fibre is 
 one, and fulfils its single function, whatever be the impression 
 which has set the fibre in motion, the only difference involved 
 in successive examples of action being connected with the 
 intensity of. impression made. As to the nerve cells, it is 
 granted that they evolve nerve energy, that they receive 
 impulse from the vibration of the nerve fibre, and propagate 
 
224 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 the impulse to other cells. But all this takes place in the 
 cellular substance of the Spinal Cord, as well as of the Cere- 
 brum; and if it does, molecular change in the cellular sub- 
 stance will not explain the facts. We thus reach on this line 
 no further conclusion than that the Cerebrum is ■& more 
 important organ, more widely influential in its relation to the 
 nerve system, than the Spinal Cord. Any characteristic which 
 can be helpful towards accounting for higher exercise of the 
 Cerebrum, than of lower portions of the nerve centre, and 
 explaining discrimination of sensations and perceptions, must 
 be distinctive of the cellular substance of the brain proper, and 
 not equally characteristic of the cellular substance wherever it 
 is found. There is consciousness of impression carried to the 
 brain, while there is not consciousness of impression carried 
 only to the spinal cord, unless pain be started there and cause 
 impulse to pass to the brain ; but this contrast cannot account 
 for higher work, such as voluntary and intelligent discrimina- 
 tion leading to conceptions of things. The supposition that 
 the action of a nerve fibre makes some impression on the nerve 
 cell does not aid the hypothesis that the grey substance of the 
 Cerebrum does intellectual work, while the grey matter of the 
 Spinal Cord does not ; or that the cellular tissue of the Frontal 
 Lobe in the Cerebrum can be credited with power of discrimina- 
 tion which does not belong to the grey matter of the Occipital 
 Lobe. That we discriminate between sensations and percep- 
 tions, and consequently form conceptions of things, are facts 
 towards the explanation of which all that is known concerning 
 the action of nerve fibres and cellular substance contributes 
 nothing. 
 
 If we next advance from nerve fibres and nerve cells to the 
 resultant sensations, these are insufficient to explain the 
 discrimination of themselves, and subsequent discrimination of 
 things. A sensation of smoothness rises in experience and 
 fades away ; a sensation of roughness follows in experience, and 
 that also vanishes; a third sensation arises, in which com- 
 mingle the effects of impression from a surface both smooth 
 and hard, and this also comes to a complete end. The same 
 sensory apparatus provides for these three distinct forms 
 of experience ; the diversity is accounted for by difference of 
 
vn.] EXPERIENCE AS CONNECTED WITH SENSATION. 225 
 
 surface acting upon the touch corpuscle; but neither the 
 objects -which come into contact with our organism, nor the 
 parts of the nerve system affected, account for the discrimina- 
 tion we make. The distinct sensations experienced give no 
 token of discriminating power. A sensation from a rough 
 surface does not perform work in the way of comparing itself 
 with a sensation from a smoother surface. A sensation which 
 is the effect of impression from a smooth and hard surface 
 does not compare itself with that from a rough surface. Mr. 
 J. S. Mill, while favouring the theory which would accept 
 a series of feelings as the philosophy of mind, has so clearly 
 shown its insufficiency, that I prefer to quote his words on 
 the subject : " If, therefore, we speak of the mind as a series 
 of feelings, we are obliged to complete the statement by calling 
 it a series of feelings which is aware of itself as past and 
 future [present?]; and we are reduced to the alternative of 
 believing that the mind, or ego, is something different from 
 any series of feelings, or possibilities of them, or of accept- 
 ing the paradox, that something which ex hypothesi is but a 
 series of feelings can be aware of itself as a series." 1 The 
 alternative "that the mind, or ego, is something different 
 from any series of feelings, or possibilities of them," is tenable. 
 The intelligence which distinguishes the sensations, and dis- 
 criminates the objects which come into contact with the 
 organism, is so different from the sensations, as well as the 
 objects, that it contemplates a past sensation, comparing it 
 with the present. And when this has given place to a third, 
 the intelligence renews the exercise of discrimination, and 
 extends its range by including all three sensations. The 
 alternative of a distinct mind is thus a tenable theory, con- 
 sistent with the facts. But the other alternative, that the 
 mind is " but a series of feelings," " aware of itself as a series," 
 is untenable, as insufficient to meet scientific requirements. 
 It proposes to regard a succession of facts as a series, without 
 discovery of any connecting bond, and on the mere hypothesis 
 of union, it attributes functions to the several members of the 
 series, which ex hypothesi they do not fulfil. On this line of 
 hypothesis, inquiry is reduced to acceptance of a "paradox," 
 
 1 Examination of Hamilton's Philosophy, p. 242. 
 P 
 
226 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 which, under the laws of scientific inquiry, must be rejected. 
 There is a unity and intelligibility of experience which it fails 
 to explain. The impressions at the periphery are distinct and 
 separate things. Any unity they have is the unity which the 
 voluntary experimenter gives them, by connecting successive 
 impressions for an intelligent end. The unity which the con- 
 sequent sensations have is the unity of personal experience. 
 Their union is where Self is observing and comparing its own 
 states, No less manifest is it that the discrimination of the 
 qualities of things, by means of the impressions they make on 
 our nerve system, is a continuous and harmonious exercise of 
 self-directed intelligence. It is dependent throughout on the 
 determination and effort of the Self which knows. It is 
 an observational result which does not follow inevitably, 
 but is recognised only when there is curiosity or interest 
 enough to mark the contrasts. Taken in themselves, as mere 
 forms of feeling, the sensations are successive experiences, 
 destitute of any element of understanding, and consequently, 
 as mere feelings, their full meaning is not disclosed. Their 
 intelligibility depends on some higher power, which they cannot 
 originate, as they do not possess any of its elements. This higher 
 power is intelligence, which, in exercising itself, knows itself, 
 and discriminates successive forms of experience, not merely as 
 facts distinct in order, but distinguishable in their own nature, 
 and capable of being interpreted so as to afford information 
 concerning things without. That the view thus taken of 
 experience is in entire harmony with the facts of human 
 history is obvious, for there is no man who does not regard all 
 things from, the point of view afforded by personal observation 
 and thought. Such a standpoint is the essential condition of 
 intelligent life ; and, as it implies superiority to things external 
 and to the contributions which such things make to the course 
 of experience, our relations to the outer world through the 
 senses are insufficient to account for our mental life. 
 
 The line of observation which has been followed as to Touch 
 might be carried out in like manner, and with like results, by 
 reference to the special senses, Taste, Smell, Hearing, and 
 Sight. But, for purposes of demonstration this is unnecessary, 
 however valuable it might be for extended illustration. I 
 
vnj EXPERIENCE AS CONNECTED WITH SENSATION. 227 
 
 prefer, therefore, to take the position now reached as a starting- 
 point for a wider course of observation. By Intelligence, so far 
 as yet appears, we mean a self-conscious discriminating power. 
 Taking now the existence of such intelligence as a fact in- 
 volved in the discrimination of our sensations, and of the 
 objects which give rise to them, I propose to inquire how far 
 illustration of still higher exercise of intelligence is afforded by 
 the use of the physical organs, known as the organs of special 
 sense ; and, in doing so, the actions of men will fall to be com- 
 pared with analogous actions of animals, so far as. such are 
 observed. 
 
 We have previously seen how elaborate is the structure of 
 the terminal organs of special sense, and how singularly adapted 
 for variety of impression, and we have now seen that there 
 is a self-conscious intelligence exercising discrimination as to 
 successive sensations arising in ponsciousness. Taking next 
 the two senses whose terminal organs show the greatest com- 
 plexity — Sight and Hearing, — I propose to inquire how far 
 these organs become the servants of Intelligence, and minister 
 to a higher life in the history of the Discriminating Nature 
 within. I desire to draw a contrast between these terminal 
 organs as merely sensitive surfaces liable to be acted upon, 
 like all sensory nerves, and as instruments for discrimination, 
 capable of being used for higher ends by a nature able to employ 
 such instruments to the utmost of their capacity, and to assort 
 and retain the results. As both Eye and Ear present surfaces 
 sensitive to external impact, they are, in accordance with the 
 uniform characteristics of the sensory system, liable to be acted 
 upon from without, irrespective of any controlling power which 
 may come from the conscious and reflective life of the man. 
 These terminal organs are even specially sensitive to external 
 influence, on account of the extreme delicacy of their structure, 
 and the consequent excitability of the delicate fibres. There 
 is sensibility wherever a sensory nerve terminates ; yet greater 
 sensibility where the Pacinian corpuscles are gathered around 
 the extremity of the nerve (p. 42), as at the tips of the fingers ; 
 but a still higher degree of sensitiveness exists in the delicate 
 arrangements of the eye and ear. Besides this, there is some- 
 thing additional in the open eye and open ear. In these two 
 
228 THE RELATIONS OF MIND AND BRAIN [chap. 
 
 cases, as also in the organ of smell, there are special con- 
 trivances for catching the impression suitable to the organ. 
 The outer arrangements of the eye are adapted for bringing 
 the light to a focus ; those of the outer chamber of the ear 
 for attracting sonorous vibration. With eye and ear con- 
 stantly open, there are sights which we cannot but see, and 
 sounds which we cannot but hear. There is, indeed, some con- 
 trast between these two senses in this respect, for we have 
 natural appliances for covering over the transparency of the 
 eye, and thereby separating the retina from the action of light. 
 The use of this covering seems to be essential for the rest of 
 the organ, by protecting it from undue continuance of nerve 
 excitement, while the action of winking seems to imply some 
 requirement for continual recurrence of temporary darkening, 
 which may be connected with the colouring matter of the 
 retina (p. 65), as it is rapidly used up by the chemical action 
 of the light. The ear, on the other hand, has no such contriv- 
 ance, by means of which we can at pleasure close it off from 
 the influence of sound. There is, indeed, one example, that 
 found in the whale (p. 186), of adaptation for closing and open- 
 ing the organ of hearing ; but that operates in the case of an 
 animal moving rapidly through the waters. With man there 
 is no such arrangement to be used at pleasure, as in the case 
 of the eye. The ear must be allowed to stand open to all 
 sounds. 
 
 I take, first, man's use of the eye as illustrating a higher 
 -exercise of intelligence than we find in the lower animals, and 
 higher than appears in human life by the use made of touch. 1 
 Even though man has much more extended and greatly finer 
 sensibility over the body than the lower animals have, he is 
 more obviously in approximation with the animals in the use 
 of touch than of sight or hearing. The presiding intellectual 
 nature, which shows its presence in exercise of the rougher 
 appliances of touch, reveals its discriminating power still more 
 in the use we are continually making of the organ of Vision. 
 The animals, with few exceptions, are indeed like us in their 
 possession of eyes. The organ of sight appears at a very early 
 stage in the scale of animate existence. The mere possession 
 
 1 Plato likens the Soul itself to the Bye : Republic, B. vi. 508. 
 
vii.] EXPERIENCE AS CONNECTED WITH SENSATION. 229 
 
 of such a sense is therefore no evidence of high intelligence. 
 It is even compatible with a very low degree of intelligence 
 indeed, being associated with low brain development. But 
 while, from the fish and frog upwards, all have eyes, a very 
 marked difference appears in the use made of these organs. So 
 far, however, is sight from being a measure of intelligence, that, 
 as we have seen (p. 126), the centre of vision is in the fish greater 
 than the entire cerebrum. Considerable difference appears in 
 the use made of vision, according as the eyes are placed in the 
 side of the head or in front. Still more is involved in the 
 muscular appliances for use of the organ, and in man these are 
 at the maximum, there being not fewer than six distinct 
 muscles connected with the management of each eye in man, 
 or ten, if we include the muscles of the eyebrows. Such appli- 
 ances obviously point to a superior use of the organ. They do 
 not of themselves supply evidence of higher intelligence, but 
 they so far favour the probability of its existence, as they show 
 that the instrument is capable of a vast variety of exercise, 
 if the Discriminating Nature be capable of bringing it into 
 full play. 
 
 In starting, however, prominence must be given to the 
 common characteristic of the eye wherever found. It every- 
 where indicates the presence of a special sensory nerve ; it is 
 an organ in all cases sensitive to the action of light, and 
 adapted to secure sensibility to the presence of external objects 
 as they reflect light. Animals and man thus start from what 
 may be named a common basis of vision. If they differ 
 greatly in the use made of the organ, the chief part of the 
 explanation depends on the discriminating power brought into 
 exercise in connection with that use. If a man and a dog are 
 moving together along a road, both may see the same objects, 
 but their modes of distinguishing objects differ greatly. If 
 both are attracted by the sight of a large-sized bird, and by 
 the heavy whirr of the grouse accompanying that bird's flight, 
 there does not appear any essential difference in the use of the 
 organ of vision on the part of the man and of the animal by his 
 side. In both cases the eyes are turned on the same object, 
 and no difference appears as to the range of vision. But 
 as the man and dog continue their way along the road, the 
 
230 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 diversity in their modes of observation becomes very marked. 
 The dog appears to see many things to wbich the man gives 
 no heed ; and it is further to be remarked of the dog that he 
 first sees objects, and next advances to .apply to them the 
 organ of smell. This mode of testing objects is in harmony 
 with what we have seen (p. 134) as to the dog's brain, that the 
 olfactory bulb is large, and is placed prominently in front of 
 the brain. In man's brain the olfactory bulb does not project 
 in front. Accordingly man makes hardly any use of the 
 organ of smell in distinguishing objects along the road ; 
 where he does use this sense, he first employs the eye to dis- 
 tinguish objects known to give forth a pleasant odour ; but he 
 makes a much more extended use of sight than the dog. 
 These elementary distinctions between man and the dog 
 would not deserve to be noted, were it not that in such in- 
 quiry as this every step in the process must be subjected to 
 scrutiny ; and as the dog is the animal of highest intelligence, 
 and most associated with man, our present purpose requires 
 that we condescend upon the most familiar and commonplace 
 distinctions. There is, however, the less need to dwell upon 
 them that they are so familiar, though they are on that very 
 account the more important. The whole set of the dog's 
 observations are such as are most closely connected with 
 smell; by far the largest number in the man's successive 
 observations are of a kind for which mere nerve sensibility, 
 whether optic or olfactory, is quite inadequate. The dog's 
 inferiority here may to some extent be consequent on want of 
 training. That question I do not stay to discuss. The pro- 
 blem under consideration is simply this, how far does the 
 ordinary use of the power of vision bear testimony to the 
 action along with it of a higher power than sensibility, that is, 
 intelligent discrimination ? My object is to show that man's < 
 observations cannot be explained by reference to mere sensi- 
 bility, such as belongs to the optic nerve. 
 
 Any set of observations will suffice to illustrate the higher 
 Tange of service assigned to the eye in human life than to the 
 same organ in the dog. The man as he walks may, for 
 example, take note of the different orders of trees growing 
 alongside the road. He distinguishes on6 as an elm, another 
 
vii.] EXPERIENCE AS CONNECTED WITH SENSATION. 231 
 
 as an oak, a third as a pine, a fourth as a mountain ash, a 
 fifth as a beech ; and at the same time he observes the com- 
 parative size and symmetry of the several specimens coming 
 under observation. Now, the materials for such distinctions 
 are provided by sensory impressions. It is true that environ- 
 ment has something to do with the man's experience, and, as 
 Haeckel has said, such a piece of " soul life" (Seelenleben), as he 
 describes it, is " ultimately referable to the elementary function 
 of sensibility." 1 But these things do not explain the result 
 described. Environment is the same for the dog and the man. 
 The elementary function of sensibility belongs also to the dog ; 
 he, as well as the man, may observe the trees, but he does not 
 classify them. So far is this classification from being a simple 
 product of sensibility, or a development of it, that while all 
 men seeing the trees recognise a difference between them, only 
 some men distinguish the various orders. Before such classifi- 
 cation takes place, the eye is brought largely into action to aid 
 comparison, being turned first upon one specimen, then upon 
 another. And it is only when this has been done, and essen- 
 tial differences are noticed, that so many trees are classified as 
 oaks, and so many more as pines. There is an exercise of 
 classifying power, and in this we reach a fuller knowledge of 
 the intelligent nature which makes the work of classification 
 altogether its own. This work is not independent of the facts 
 of nature, nor of physical sensibility, but yet it is accomplished 
 by a process superior to both. Confirmatory evidence, which 
 need not be considered in detail, may be gathered from every 
 department of skilled workmanship depending largely on the 
 eye. 
 
 Still further in advance of this is the extent to which the eye 
 ministers to the sense of beauty. The beauty of nature is in a 
 measure reflected in every eye gazing upon it, but it is really 
 seen only by the observer who discriminates the various points 
 of the landscape. The scene spread out before the view at any 
 point of the road is the same to all observers, yet how different 
 according to the training of the inner life ! To some it is a 
 source of pure, refined, and intense enjoyment ; to others it is 
 merely a gathering of fields and mountains, with a rapid flow- 
 
 1 Die heutige EntwickehmgsUhre, p. 1 4. 
 
232 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 ing stream running in the hollow. There is a sensibility other 
 than that of the eye, a sensibility which can be moved and 
 cultivated only by an exercise of discrimination which is beyond 
 the reach of nerve sensibility. Without the sensitiveness of 
 the retina, and conductivity of the optic nerve, we should lose 
 the whole ; and so we have learned to compassionate the loss 
 sustained by our fellow-men whose blind eyeballs are incapable 
 of receiving such impressions. But the immense difference of 
 experience on the part of those who gaze unrestrainedly on 
 the scene shows that there is a sensibility which is touched 
 only by exercise of discrimination, and is cultivated by a more 
 careful and habitual use of the distinguishing power which 
 ministers to it. Large is the reward of such training, increasing 
 delight with widened experience. To choose well the stand- 
 point, and occupy it at fit time, when the few thin clouds 
 floating overhead are tinged with radiance, when the mountain 
 heights in the far distance stand out on either hand in sharpest 
 outline against a clear blue sky ; when every bold feature on 
 the mountain-side is lighted up, having its brightness sustained 
 by the darkened recesses behind ; when the tumbling waters 
 are sparkling in the sunshine, and the long spreading pool 
 close at hand is traversed by a pathway of golden brightness, 
 is to fill the inner being with calm delight, soothing and 
 elevating in its influence. Many eyes behold the scene with 
 inner nature little moved. Yet from many a humble home 
 in these remote uplands there comes forth at the eventide the 
 quiet observer, seeing, appreciating, and rendering thanks 
 to the Creator, who with liberal hand spreads such profusion 
 of beauty and grandeur over lone mountain sides and narrow 
 glens. 
 
 Other and still higher forms of beauty there are than those 
 which nature discloses even when bathed in the glories of the 
 sunshine. But enough has already been done to demonstrate 
 the demand upon an inner power of discrimination for true 
 development of aesthetic taste, without carrying the argument 
 up to these loftier regions of human experience. It may suffice 
 to suggest that the true artist, while depending on the sensi- 
 bility common to our organism, depicts his ideal scenes, and 
 presents to our admiration combinations never witnessed in the 
 
vn.] EXPERIENCE AS CONNECTED WITH SENSATION. 233 
 
 most favoured lands. He who interprets nature can best illus- 
 trate nature, and help us all in the work of interpretation. 
 By his power of discrimination and cultivated sensibility, and 
 by skill in colouring attained through apt and patient use of 
 vision, he can make the canvas to reflect a beauty far away 
 from us, or present startling combinations, which, if they re- 
 flect anything, reflect only the fancies of an inner life where 
 visibility is unknown. 
 
 What has been said as to sight may be extended in similar 
 manner to the sense of hearing, provided for by arrangement 
 of successive chambers adapted to the action of sound-waves, 
 and their effects on manifold minute and sensitive points of 
 the auditory nerve. It is quite unnecessary to produce an 
 extended line of evidence. Here as elsewhere the sensory 
 arrangements have common features such as provide for sensi- 
 bility in all animated existence. Some animals are indeed 
 more sensitive to sound than others ; but in no case is the 
 auditoiy arrangement at all so conspicuous as is the olfactory 
 bulb in many cases. Auditory sensibility is, however, a charac- 
 teristic shared with man by all the higher orders of animals. 
 The contrast between man and animals may be carried along 
 a single line of evidence by reference to the influence of 
 music. Many animals show lively sensibility to the effects 
 of harmony. Very low in the scale the appreciation is found, 
 as in the case of the singing birds. On an intermediate 
 part of the scale, the appreciation is decidedly small, as with 
 the cat and the dog; higher up the scale, it becomes again 
 much greater/as in the horse and the elephant, either of which, 
 after a little training, will move in time, the one animal mani- 
 festly in his tread, the other by the oscillation of his trunk. 
 Among birds the contrast is great between the smaller songsters 
 and an imitative bird such as the parrot. The latter can be 
 taught to whistle an easy air, and, after the tune has been 
 learned, he will repeat the performance with manifest delight. 
 But let the family begin some concerted piece of music, in 
 which the harmony of instrument and several voices is in- 
 volved, and the contrast in effect is -great, — the canary sings 
 with high delight, its throat swelling with effort to share in 
 the performance, — the parrot simply screeches, ill-naturedly 
 
234 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 repeating a succession of the most sharp discordant notes it 
 can produce. In my own home I have daily illustration of the 
 contrast. The merely imitative animal has far less sensibility, 
 and has narrower range of capacity, but it has ample supply of 
 the irascible tendency, and it shows its anger as resolutely as 
 the smaller bird shows its delight. The cat and dog, on the 
 other hand, evince little appreciation of music, the cat being 
 comparatively indifferent, the dog sometimes uneasy, showing 
 a sense of the disagreeable under more complicated movements, 
 tempting him to disturb the company by barking. On the 
 other hand, there is no one who marks the graceful movements 
 of a horse keeping time to the performance of an orchestra, or 
 the more ungainly swaying of an elephant marching in front 
 of a military band, who can fail to be interested in the sight. 
 Some share of the sensibility which so delights and soothes 
 the human race is manifestly experienced by many of the 
 animals. 
 
 Very far in advance of all this is the work of the composer, 
 from whose pen come the productions demanding study from 
 others, if they would understand them, and become interpreters 
 of the master. Or, to take an illustration drawn from lower and 
 more common ranges of experience, there is an immense advance 
 upon all that is characteristic of the ordinary use of an organ 
 of hearing, in the intellectual exercise of one who understands 
 the works of a great master in musical composition, and shares 
 in feeling unknown to man save by such appreciation. To 
 understand and delight in the music of Handel or Mozart, of 
 Beethoven or Mendelssohn, implies large exercise of discrimi- 
 nation as to musical expression. Musical feeling is not feeling 
 apart from intelligence, but feeling essentially dependent on 
 intellect. Wave-sounds striking on the tympanum, followed 
 by vibrations of the auditory nerve, do not account for 
 what Felix Mendelssohn meant when he wrote of having a 
 chorus " in his head," or " two new symphonies haunting his 
 brain." There is a sense in which it may be said that these 
 forms of experience are " ultimately referable to the elementary 
 function of sensibility," for it may be allowed that a Mendels- 
 sohn or Beethoven born deaf would never have become the 
 Felix Mendelssohn or the Ludwig van Beethoven whom we 
 
vii.] EXPERIENCE AS CONNECTED WITH SENSATION. 235 
 
 know and admire, any more than Kaphael or Michael Angelo 
 could have become what they were had they been born blind. 
 Yet, undeveloped though they had been, the artist would still 
 have been within all the four, only awaiting unfolding in a 
 more favouring sphere, and giving out occasional tokens of the 
 indwelling power, as stray impulses strike in upon the region 
 of inner life by other pathways than the auditory or optic 
 tracts. It is the inner life which makes outward circumstances 
 what they are for such a soul as that of Beethoven ; it is a dis- 
 crimination unattained by nerve susceptibility. If any confir- 
 mation were needed, it is supplied in the sombre experience 
 and sad restraint laid on the life of Beethoven, when deafness 
 came upon him, and it proved impossible for him to hear the 
 performance of his own compositions, even when he was him- 
 self the conductor. It is thus the hampered soul expresses 
 itself, " One of my most precious faculties, that of hearing, has 
 become very defective." 1 "I must withdraw from everything. 
 My best years will thus pass away, without effecting what my 
 talents and powers might have enabled me to perform." 2 Who 
 can describe the wealth of musical composition which came 
 from that hampered mind revelling silently up and down the 
 vast ranges of musical combination ? Who can fail to experi- 
 ence a tender compassion, or to recognise tokens of superiority 
 to the disabled organism, as Beethoven seeks the help of touch 
 by striking the notes of his piano ; or maintains his post with 
 the conductor's baton, aided by sight of the bows as they sweep 
 up and down, while he reads the score ? 
 
 Or, let us take an example from another standpoint, illus- 
 trated by the brighter experience of Felix Mendelssohn, whose 
 inner life is seen daily providing fresh enjoyment for the 
 sensitive ear, and for those finer, deeper sensibilities which 
 all composers share. Internal discrimination of the varying 
 phases of human emotion, and sensitive appreciation of musical 
 combinations expressive of the finer shades of feeling, together 
 afford the only possible explanation of the new composition 
 which at length finds outward expression by action of the 
 fingers along the key-board, followed by resonance through the 
 auditory chambers, and vibration along the auditory nerve, 
 1 Beethoven's Letters, vol. i. p. 17— Lady Wallace. 2 lb. p. 19. 
 
236 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 to react upon that feeling out of which the performance 
 originated. " When I have composed a piece just as it sprang 
 from my heart, then I have done my duty towards it." 1 
 If a composition of a special kind is asked of him, so much 
 has the region of thought to do with his work, that he will 
 say, "Till I have the words, is it not better I should try 
 nothing?" 2 If we would judge of what may be described as 
 musical inspiration, we may take this reference to his compo- 
 sition of sacred music : " I have recently written a good deal of 
 sacred music, because this is as much a necessity to me as the 
 impulse that often induces people to study some particular 
 book, — the Bible, or others, — as the only reading they care for 
 at the time." 3 So also in a region of discrimination superior to 
 all the distinctions which sensory apparatus supplies, we find 
 his refusal to attempt music for libretti stained with expres- 
 sions of immorality, and his deep aversion to many forms of 
 operatic performance : — " I have no music for such things. I 
 consider it ignoble ; so if the present epoch exacts this style, 
 and considers it indispensable, then I will write oratorios."* 
 Fit utterance for the artist who, after having said that he must 
 compose as the piece springs from his heart, adds, "And 
 whether it brings hereafter fame, honoiir, decorations, or snuff- 
 boxes, etc., is a matter of indifference to me." 6 There is some- 
 thing grander in a Beethoven, or a Mendelssohn, a Schumann, 
 or Schubert, than can be explained by a finely-strung and 
 sensitive nervous system, even though it be no less clear 
 that no one of the number could have been to us what he 
 became, without the nerve sensibilities with which he was 
 endowed. 
 
 1 Mendelssohn's Letters from Italy and Switzerland, p. 203 — Lady Wallace. 
 » lb. 3 lb. 4 lb. p. 300. 6 lb. p. 203. 
 
vin.] EXPERIENCE CONNECTED WITH MOTOR ACTIVITY. 237 
 
 CHAPTEE VIII. 
 
 EXPERIENCE AS CONNECTED WITH MOTOR ACTIVITY. 
 
 The facts connected with the activity of the motor system, 
 which now fall to he considered, are closely related with those 
 attending on the activity of the sensory system. The relation 
 between the two systems is, as we have seen, very intimate. 
 They are, indeed, two divisions of one system, and cannot he 
 contemplated altogether apart from each other. This relation- 
 ship will, therefore, determine the order of inquiry in the 
 present instance. 
 
 First there are the facts which illustrate reflex action, or 
 motor activity induced by the sensory apparatus, without con- 
 sciousness on our part. Next in order are the facts of sensori- 
 motor activity, when, as the result of a conscious impression, 
 there is movement of certain muscles. We here come upon 
 the classification of muscles, previously alluded to as "voluntary 
 muscles." Passing to a third division of facts, we find examples 
 of motor activity which cannot be traced to any sensory impres- 
 sion, but depend upon personal determination. And still 
 further beyond these, we shall reach a class of actions which 
 cannot be explained by any recognised activity either of the 
 sensory or of the motor apparatus. 
 
 Dr. Marshall Hall showed (p. 80) that the sensory nerve 
 may be an " excitor nerve," and that many of the sensory 
 nerves are capable of providing for motor activity through the 
 spinal marrow. 1 The nerve force, as a stimulating power, acts 
 along the double lines, the result being reflex action. " The 
 vis nervosa, or motor influence, acts in directions from the 
 branches of the nerves towards their trunks into the spinal 
 marrow, and upwards as well as downwards in the spinal 
 marrow, . . . and lastly in reflected directions into the 
 1 Diseases and Derangements of the Nervous System, p. 42. 
 
238 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 extremities." 1 Such action is illustrated in the case of a 
 decapitated animal while the vitality of the nerve system 
 remains. Stimulation taking effect at the extremity through 
 a sensory nerve, reacts in movement of that extremity. A 
 duck will run for a considerable distance after being decapi- 
 tated. There is an example on record of a tiger running for 
 half-a-mile after having been shot through the heart. 2 In 
 our ordinary experience, a touch on the border of the eye-lid 
 leads to its instantaneous closing. If we only make a begin- 
 ning in walking, contact with the ground will so act upon the 
 sensori-motor apparatus as to keep up the exercise. In this 
 way the action of many of the vital organs is explained, as for 
 example respiration, and such an act as that of swallowing. 
 These then are examples of reflex action, a phase of motor 
 activity illustrated in the lowest forms of animal organism 
 (see above, p. 123). Such activity is accomplished in the 
 higher orders of animals without interposition of the cerebrum. 
 This lowest example of nerve action is common to all forms of 
 animal life. Eefiex action is, therefore, the most complete 
 illustration of the similarity of nerve organism up the whole 
 scale of animal existence, including the physical nature of man 
 as the most elaborate structure of the whole. We are here 
 contemplating facts at the opposite extreme from those which 
 imply discrimination and voluntary determination. By the 
 law of nerve action, motor activity is in such cases inevitable 
 when sensory stimulus is applied. 
 
 From this common level of purely reflex action we rise a 
 stage higher to take account of sensori-motor activity, involv- 
 ing consciousness of sensation and of muscular action as two 
 distinct facts in our experience. This class of actions is best 
 illustrated by reference to our sense of pain, and the inevitable, 
 because spontaneous, shrinking of the muscles subjected to 
 injury. At this stage we reach an intermediate position in 
 the order of muscular actions. This higher class of actions is 
 
 1 Diseases and Derangements of the Nervous System, p. 43. 
 
 2 " Afterwards upon opening this tiger, we found it had been shot through 
 the heart, and had actually run full half-a-mile after receiving the mortal 
 injury." — Bradley's Narrative of Travel and Sport in Bitrmah, Siam, and the 
 Malay Peninsula, p. 83. 
 
viii.] EXPERIENCE CONNECTED WITH MOTOR ACTIVITY. 239 
 
 connected with reflex actions on the lower side, and with the 
 exercise of voluntary power on the higher. As in the case of 
 reflex actions, this higher, form of motor activity is provided 
 for by means of relations established between the sensory and 
 the motor apparatus. There is a mechanical contrivance for 
 its execution. Nerve sensibility with nerve energy supplies 
 the conditions requisite for securing motor activity when the 
 needful impression is made on the sensory nerve. If any one 
 apply a needle or a lighted match to the hand of a person 
 unaware of what is being done, the hand will be instantly 
 withdrawn. We have thus an example of spontaneous motor 
 activity, as in the lower order of cases where consciousness is 
 wanting. 
 
 But in relation with such acts as these, we have clear evi- 
 dence of a voluntary element. Whether such element may 
 mingle in any measure with the experience of lower animals, 
 may be difficult to decide. I do not here deal with that ques- 
 tion. There is no uncertainty as to the fact in our own expe- 
 rience. We are here brought to the threshold of the whole 
 problem concerning will-power. That power is recognised 
 working in relation with nerve force, but it is recognised as 
 also distinct from it, and the distinction is all the more clear 
 on account of the diversity of law operating in the two cases. 
 "The one power comes into competition with the other, thereby 
 affording the best possible means of experiment in order to 
 establish the difference. Examples are not difficult to find, 
 for they are sadly plentiful under the general liability of men 
 to suffering. Voluntary endurance of pain in any form, with- 
 out shrinking, introduces the new element, presenting a con- 
 trast to ordinary motor activity. It may be exemplified in 
 mere diversion, as in the case of a cadet in the United States 
 Military College at West Point, who on a warm summer 
 evening, bared his arm and endured mosquito bites without 
 wincing, until an artful comrade, coming behind, tried him 
 with the point of a red-hot wire. The power of self-restraint 
 in checking nerve action is often seen as a manifestation of 
 high courage in the surgical department of our public hos- 
 pitals. Some threatening malady has attacked the system, and 
 the sufferer, who has placed himself under the surgeon's care, 
 
240 7'HE RELATIONS OF MIND AND BRAIN, [chap. 
 
 submits to an operation without a wince or a groan. It is 
 recorded of an able-bodied seaman that, after having quietly 
 submitted to an operation, he cried out when a needle was run 
 into his arm by the dresser who was binding up the wound. 
 The dresser expressed surprise that one who had endured the 
 operation itself so quietly, should cry out under the puncture 
 of a needle. To this the sharp-witted tar promptly replied, 
 that he expected the cut of the knife, but he did not expect 
 the prick of the needle. Expectation, and the preparedness of 
 mind it implies, makes all the difference, and that difference is 
 as wide as the distinction between voluntary and involuntary 
 action. Two forces meet each other, and the will-power masters 
 the nerve-power, the result being inhibition of motor activity ; 
 that is, an effectual restraint on the ordinary law of action, 
 which regulates the sensory nerves and cells, with the corre- 
 lated motor cells and nerves. 
 
 There are, no doubt, certain physical characteristics which 
 have a bearing on the balance of motor activity and will-power. 
 There are persons of a more acute sensibility for whom even a 
 slight form of injury is much worse to endure than greater 
 injury is for others. There are conditions of physical prostra- 
 tion in which extreme nervous irritability makes muscular 
 control next to impossible. Such a case illustrates the ascend- 
 ency of the physical, with the temporary subjection of the 
 mental power. And there are cases in which a patient passes 
 through the earlier stages of a protracted operation with great 
 self-command, and yet completely loses control during the 
 later stages of it, vanquished by exhaustion and anxiety as to 
 the result. But these, and similar considerations, throw no 
 doubt over the distinction between the laws of motor activity 
 and those which apply to control of the will. They bear upon 
 modifications of experience appearing in different cases ; but 
 they leave untouched the fact, that while the laws of the excito- 
 motor system provide for motor activity, personal resolution 
 places a restraint upon the nerve system, preventing the action 
 which would otherwise result. 
 
 If the full significance of this be noted, the contrast of 
 powers operating is very marked. The laws of motor activity 
 which regulate the nerve system are perfectly definite. The 
 
vm.] EXPERIENCE CONNECTED WITH MOTOR ACTIVITY. 241 
 
 infliction of pain involves a convulsive movement of the sen- 
 sory nerve; this operates upon the sensory cell, whence the 
 impulse is communicated to the motor cell, and thence by the 
 motor nerves to the muscles. But what we have, in addition 
 to this, and in direct contrast, is a restraint imposed upon the 
 natural action of nerve force along the double line. It is true 
 that inhibitory action is characteristic of some parts of the 
 nerve system itself. Thus certain conditions of body imply an 
 inhibitory action, through the nerve system, upon the heart, or 
 lungs, or stomach. But there is no law applicable to the sen- 
 sory and motor apparatus which implies the imposition of a 
 check on the transmission of the impulse communicated at 
 the peripheral extremity of the sensory nerve, when an inci- 
 sion is made. Spontaneous shrinking is the one inevitable 
 result under the laws of nerve action. 
 
 On the other hand, it is matter of clear and unquestionable 
 experience, that personal determination is the explanation of 
 the restraint imposed in such cases as those to which I am 
 referring. The contrast between preparedness and unprepared- 
 ness for endurance is the presence or absence of personal 
 determination to endure suffering for a clearly recognised end. 
 And the evidence is most striking, as it is most valuable for 
 my present purpose, when endurance of suffering does not 
 take place under pressure of a greater agony to be escaped, but 
 under a quiet and deliberate resolution in order to avoid an 
 anticipated yet remote result. For demonstration of the 
 present point, there is great difference in the value of the 
 evidence coming from the sudden resolution to submit to the 
 extraction of a tooth on account of incessant torture from 
 severe toothache, and that coming from the quiet determination 
 to submit to surgical treatment when there is no present 
 suffering to awaken a powerful desire for deliverance from 
 pain r and when the advice of a skilful practitioner is the only 
 ground for submission. A dog suffering torture will put itself 
 in the hands of a familiar and trusted keeper, and submit to 
 increase of suffering while a thorn is being extracted, without 
 showing any disposition to bite his benefactor. But dogs 
 troubled with a swelling on the limb do not consult, do not 
 listen to advice with which a consultation closes, and do not 
 
242 THE RELA TIONS OF MIND AND BRAIN. [chap. 
 
 deliberately prepare for the operation which veterinary skill 
 may suggest as desirable in the case. It is deliberation first, 
 and power of control over nerve action consequent upon such 
 deliberation, which together illustrate the strength of will 
 power in conflict with nerve power. In such a case it is 
 not mere power of endurance which is tested. That may be 
 tried in the experience of any sentient being. It is power of 
 self-control for a contemplated result to be reached in the 
 future, and not merely for present escape from insupportable 
 anguish. 
 
 From this I pass to the third, and higher phase of action, 
 where motor energy is brought into use as the servant of 
 intelligence and will, in absence of any sensory impulse, or 
 physical condition, which could account for motor activity 
 under laws regulating the nerve apparatus. In our experience 
 there are examples of motor activity not explained by sensi- 
 bility to external influence, — nor by the power of the cellular 
 tissue in the cerebrum to evolve nerve energy, — but which 
 are accounted for by previous deliberation on our part, and 
 consequent determination to act for an end which has already 
 been matter of choice. The actions referred to are not of any 
 singular or high order illustrating peculiar power, but are such 
 as occur in every man's life all hours of the day. Every 
 man using a tool in handicraft, every one uttering a sentence 
 in expression of his thoughts, every person writing a few 
 lines for the same end, illustrates the ascendency of intelli- 
 gence and will over the motor system. There is no need at 
 this point for founding anything upon the additional plea that 
 handicraft, and spoken discourse, and written language are 
 peculiar to men, distinguishing them from lower animals. 
 These actions are illustrations of a fundamental feature of 
 human life, regulation of motor activity by personal thought 
 and purpose, and it is better to deal with the fact of such 
 regulation, as exemplified in thousands of cases, even where 
 human actions, so far as outward appearances indicate, closely 
 resemble the actions of the lower animals. I take them, there- 
 fore, only as examples of a distinct class of human actions. 
 
 The new features involved will be most readily ascertained 
 by taking a familiar example. Skill in workmanship by the 
 
vm.] EXPERIENCE CONNECTED WITH MOTOR ACTIVITY. 243 
 
 apt use of tools involves considerable variety of action. In 
 a PPtying the tool to wood or other material, the motor apparatus 
 is brought into use, giving exercise to muscles, nerve fibres, and 
 motor cells. Such actions depend, in the first instance, upon 
 contractility belonging to the muscles, and excitability of the 
 nerves which bring the muscles into action. Thus far the 
 originating power is in the nerve cell. But an explanation of 
 the activity of the nerve cells is required. There is a selection 
 of nerve cells and fibres as those which alone are suited for 
 bringing into exercise the muscles of the two arms required for 
 management of a tool. But cells, fibres, and muscles are not 
 objects of contemplation to the worker. His concern is with 
 the material and the tool, and with his own purpose or inten- 
 tion in the use of them. The matter of interest to us is what 
 takes place before the tool is lifted and directed ; and there- 
 after how much is involved in acquired skill of the workman, 
 resulting from frequent return to his work. The very simplest 
 aspect of such work includes observation of the tool to be 
 used, and of the material to be worked upon ; determination to 
 grasp the tool and apply it ; a definite plan or purpose as to 
 what is to be accomplished by means of the work ; and con- 
 tinual exercise of intelligence and will as the work proceeds, 
 adapting each movement so that it may contribute to the 
 desired end. The primary exercises of observation involve 
 mere sight of the tool and of the material. In a sense 
 this observation may be quite possible to an animal such as the 
 dog, though there may be reason enough for supposing that, to 
 the dog, a chisel or plane is merely a thing, and not a tool or 
 instrument ; and that the piece of wood is only a thing, and 
 not material out of which some other thing may be produced. 
 The sight of the tool and the material goes a very little way 
 towards explaining the action of the workman. The know- 
 ledge which physiology affords as to the laws of action of the 
 motor apparatus is an additional contribution towards the 
 explanation. "When, however, we have combined these two 
 elements — sight and its influence, the motor cell and its 
 impulse — the main part of the explanation is wanting. The 
 origin of the action, the intelligent purpose of continued work, 
 and the sustained effort extended over a considerable time, sus- 
 
244 THE RELA TIONS OF MIND AND BRAIN. [chap. 
 
 pended for a season, and renewed again : these are the most 
 important features in the case. Without these the action is 
 reduced to a lower level, and becomes nothing more than 
 mechanical exercise of a reflex type, such as is exemplified in 
 a person continuing to walk along the street. But some under- 
 standing of his work, some conception or ideal of what is to be 
 made, and some regard to size and proportions, are essential 
 before the work is begun. All these are personal occupations 
 of which the moving arms give no tokens ; they are essential 
 antecedents of motor activity, which is only the mechanical 
 consequent of volition. Intelligence is needful for handicraft, 
 and it is in the same sphere as that in which the intelligence 
 works, that the determination is formed which originates motor 
 activity. Until that volition is formed, there is no motor 
 impulse; as soon as the volition is brought to bear on the 
 organism, the motor impulse speeds on its way, and forthwith 
 the muscular energy is liberated and actively at work. We 
 may calculate the time involved in the course of motor activity, 
 just as it has been found possible to reckon the time taken to 
 experience an impression made on a sensory corpuscle. But 
 in the order of events, thought will come first, and volition or 
 self-determination second, as facts known with certainty, that 
 is, elements of our own experience, while thereafter we allow 
 for excitation of the motor cell, then of the nerve, and ulti- 
 mately of the muscle, facts which are not known in experience, 
 but which are admitted on scientific grounds to be the organic 
 conditions of the visible activity of the arms. We are here 
 dealing with successive features of personal action which are 
 indisputable. Thought is the origin of volition, and volition is 
 in this case the cause which liberates nerve energy, and the 
 nerve energy becomes the cause which liberates muscular 
 energy. If the relation of the two first-named actions to the 
 muscular activity be disputed, it can be made matter of 
 experiment. A resolution will be sufficient to lift the tool at 
 any moment; resolution not to touch it will suffice to keep 
 the arm at rest, and even to throw it into a rigid attitude if any 
 attempt be made by others to bring the hand into contact with 
 it against our will. As to the facts, including thought, volition, 
 nerve action, and muscular action, there is no room for doubt ; 
 
viii.] EXPERIENCE CONNECTED WITH MOTOR ACTIVITY. 245 
 
 the certainty as to the two first being that of experience, of the 
 two last that of scientific testimony. 
 
 Possible controversy is thus restricted to the theory which 
 may be propounded by way of accounting for the two first 
 facts. The theory that action and reaction of nerve tissue 
 carries the explanation of all that belongs to human life must 
 try itself here, — must here make good its claims, or fail utterly. 
 It has been said that " all soul-life is ultimately referable to the 
 two elementary functions of sensation and motion, and their 
 conversion into reflex action." What is required is demonstra- 
 tion of the assertion in the case before us. Here is the motion, 
 — industrious use of the arms in the exercise of mechanical 
 art. Where is the sensation and where the evidence of a reflex 
 process from sensory activity to motor ? To suggest that the 
 sensation of grasping the tool causes the action which leads to 
 its use would be of no avail. The suggestion is at fault on 
 both sides. In the case of continuous action it may be 
 admitted that the sensation involved in grasping the tool con- 
 tributes some stimulus to the motor apparatus brought into 
 activity, but this would be a continuous, uniform impulse as 
 long as the activity lasted, and would not account for the 
 origin of activity, or for regulation or guidance such as is 
 involved when the results of handicraft are worked out. To 
 make plain the distinction between reflex and regulated 
 activity when they commingle in the same occupation, let us 
 take the illustration of weaving, where the worker uses the 
 treadles and the shuttle. The pedal and the manual work 
 illustrate the two opposite conditions of activity. There is 
 voluntary exercise in starting the whole process, for the work is 
 one, as it is one man's work, and depends upon personal resolu- 
 tion for its being attempted. But when it is begun, the feet follow 
 the hands, not the hands the feet. The manual activity is the 
 determining feature. And if we inquire how this appears, the 
 answer brings out the distinction. The eyes are guiding the 
 hands, but they are not in the same way directing attention on 
 the movements of the feet. And the guidance of the hands by 
 sight is regulated according to a pattern ^hung within reach, 
 and which is constantly being compared with the web, while 
 the shuttle flies backward and forward. The feet are playing 
 
246 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 an essential but quite subordinate part; nerve sensibility is 
 enough to provide for such activity, and their movement will 
 continue without direct intention so long as there is nothing to 
 disturb. The hands, in like manner, are doing an essential 
 part, but theirs is a far more important part, and illustrates 
 action of a higher order. Intelligence is not directing the 
 feet, intelligence is directing the hands. Under guidance of 
 eyesight, the hands are working out what the worker aims at 
 producing ; and any deflection or deficiency is not only seen 
 as fact, but recognised as departure from the design. By per- 
 sonal determination the hands are stopped, as by the same 
 means they were kept in motion, while, as an inevitable con- 
 sequence of what has happened, the feet are stopped as a mere 
 mechanical result, without any express determination concerned 
 with their activity. The manual activity is voluntary, the 
 pedal is reflex ; the latter is explained by the laws of activity 
 which belong to a sensori-motor apparatus, the former is not. 
 A case in contrast is presented in playing upon the organ, 
 where feet and hands are equally engaged in the same exercise, 
 all four being employed in execution of the piece of music. 
 Here feet and hands together illustrate voluntary movement, 
 an illustration which is of special value, as showing how the 
 single power of will takes complete control of a whole series 
 of cells, nerves, and muscles determining their co-operation for 
 a harmonious result. If, then, we take a phase of handicraft 
 in which the feet are not engaged, but the whole work is done 
 with the hands, we have an example of muscular activity 
 which is throughout voluntary, that is, continually determined 
 by exercise of will power, in contradistinction to activity 
 which is accounted for by sensori-motor relations. To suggest 
 that the grasping of the tool is sufficient to account for the 
 manual labour done by skilled workmanship is to overlook 
 the direction which the eyes give to the hands, and to forget 
 the light of intelligence thrown from the inner sphere, as well 
 as the sunlight from the outer. It is to forget the essential 
 difference between mechanical action and voluntary activity, — 
 the difference between the machine and the worker. The 
 machine can work as well in the dark as in the daylight ; not 
 so the artificer. Keflex action may readily enough be done 
 
vin.] EXPERIENCE CONNECTED WITH MOTOR ACTIVITY. 247 
 
 by men without light to guide ; it may even be continued when 
 the agent is fast asleep ; but voluntary activity can be done 
 only when the agent brings the directing power and the con- 
 trolling power belonging to his personality into effective exer- 
 cise. The muscular activity of man is not all of a single type, 
 and does not admit of being brought under a single form of 
 explanation. There is reflex activity, and there is voluntary. 
 The attempt to identify them is a failure. A sensori-motor 
 scheme is insufficient to embrace the most simple and familiar 
 forms of human activity. 
 
 Passing from the illustration of reflex action, suggested as 
 the normal type of all muscular action, we have now to con- 
 template more particularly the origin of such action as is 
 exemplified in ordinary handicraft. Here we must inquire 
 what is the exact nature of will power, — what we mean by 
 personal resolution or determination, as an alleged fact standing 
 at the opposite extreme in human experience from sensory im- 
 pression, in which some would affirm that all muscular activity 
 originates. Here also we must try the suggestion that the 
 action and reaction of the nerve system is adequate to ac- 
 count for human activity. What we mean by volition or 
 exercise of will power is best shown, in the first instance, by 
 marking its contrast with nerve action. It is not that which 
 moves the muscles, but that which moves the nerve cells 
 to act upon the muscles. It is not that which moves the 
 limbs, but that which determines that they shall be moved. 
 In its lower and simpler aspect, this may be illustrated by 
 reference to sensory activity. A falling stick touches the 
 hand, or a neighbour jostles the elbow. By contact of some 
 external body, an impulse is given to the sensory nerve which 
 is transmitted to the sensory cells. Let us turn now to motor 
 activity. In so far as the originating power acts wpon the 
 motor apparatus, its action is, in a sense, analogous to that 
 which produces tactile impression, — it operates as an exter- 
 nal power, that is external to the apparatus. Or, to take 
 a form of expression more familiar, there comes from an 
 inner sphere, from the region of personal experience, an im- 
 pulse which acts upon the motor cell, and throws it into 
 activity. That which acts upon the motor cells is as certainly 
 
248 THE RELA TIONS QF MIND AND BRAIN. [chap. 
 
 external to the system as is the object which comes into con- 
 tact with the sensory system. But in the case of voluntary 
 muscular activity, that which operates acts directly on the cell. 
 And what is not reflex, as not being the product of movement 
 of the sensory nerve, must be accounted for by energy from 
 some other quarter, that is, from a sphere external to the nerve 
 system, though within the nature of the person. The working 
 of the arms by any craftsman is not a case of spontaneous 
 working of the nerve cells. It is not alleged, in such a case, 
 that nerve cells evolve nerve energy simply because their supply 
 of energy is so great that it seeks outlet, or forces for itself a 
 path of activity. The activity is, indeed, impossible without 
 nerve stimulus and muscular energy, but its present manifesta- 
 tion and direction are not explained by these, but by the 
 workman's purpose. Consequently, this purpose must be 
 something distinct from the motor apparatus, — something which 
 acts upon it, — just as certainly as the sensory apparatus is 
 shown to be distinct from the motor on which it acts. By 
 this merely negative test the theory of action and reaction 
 within the nerve system is brought into perplexity. The facts 
 of motor activity require further explanation, some power 
 external to the motor apparatus, just as obviously as the facts 
 of sensory activity. These two divisions of the nerve system 
 act singly as well as unitedly ; and in the former case the com- 
 munication of impulse must come from beyond the apparatus 
 itself. Further and most striking illustrations of this fact 
 connected with the action of the motor apparatus might be 
 given by reference to the other two examples previously named, 
 articulate expression of thought and written expression. But 
 there is no need for extending the lines of evidence beyond 
 what has been already done,, and I content myself with naming 
 the examples as additional tests. To suggest that a man's 
 words are accounted for by external influences, such as the 
 appearance and statements of a friend, is to contribute nothing 
 to the present inquiry. No one can listen to a public speaker, 
 when carefully guarding his words, without admitting that 
 while external circumstances have to do with what is spoken, 
 their influence tends only more fully to illustrate self-control, 
 by revealing intelligent appreciation of what is befitting. 
 
via.] EXPERIENCE CONNECTED WITH MOTOR ACTIVITY. 249 
 
 I now take the more positive side of the problem. What 
 is to be said of the Will, as the power which acts upon nerve 
 power ? The facts of personal experience supply the answer. 
 These facts alone can provide evidence on which our account 
 of will power can proceed. The facts are familiar, much better 
 known than those connected with nerve action. Their nature 
 will be best indicated by passing from motor activity and its 
 apparatus, to consider the true rise of voluntary muscular 
 effort. A craftsman has some conception of an object, or some 
 plan before him of an article to be manufactured ; he occupies 
 himself with the best methods for its construction ; he resolves 
 to make the attempt, and by an act of his own will he gathers 
 his tools around him and begins work. It is exactly in the 
 same manner the artist begins who would produce a picture, 
 and the author who would write a book. Thought and will 
 are connected in this early stage, which is the true commence- 
 ment even of muscular action, when it is properly described as 
 voluntary. So it is when a person gives audible expression to 
 his opinion on any question. His thoughts on the question, 
 and the feelings awakened by them, are not the cause of utter- 
 ance. Such thoughts and feelings are often present in his 
 consciousness, without finding expression. Kb occasion seems 
 to arise for uttering them, or at least he feels no inducement in 
 the circumstances. At times, when the thoughts and feelings 
 are present, silence as to their nature is matter of personal 
 determination. There is a deliberate purpose to refrain from 
 expressing his thoughts. And when he does speak, he wills 
 to use his voice, and guides it in the process of articulation 
 needful to convey to others what he wishes to state. The 
 process is still the same when he records his thoughts by 
 writing. As in the previous case, he wills to formulate his 
 thought, ponders the matter, and selects carefully the fittest 
 forms of expression. The sole difference is found in the mus- 
 cular apparatus he brings into exercise. He now wills to use 
 the muscles of his arm, and by aid of the pen he produces the 
 written characters which are conventional signs for his mean- 
 ing, easily interpreted by those familiar with the language he 
 employs. Personal determination or will is the origin of all 
 three actions. The points of difference and of similarity in the 
 
250 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 three cases bring out the common feature connected with their 
 commencement, namely, volition. In a sense the three actions 
 are similar throughout. They are only different examples of 
 the same class of actions, known as voluntary muscular acts. 
 All three begin in an exercise of personal determination or 
 power of will ; all imply activity of motor apparatus ; all involve 
 efficient use of muscular energy ; and all accomplish a previ- 
 ously contemplated and intelligent end. In certain aspects each 
 action is different from the other two. The difference is found 
 in what belongs to the outer field of activity ; the closest re- 
 semblance in what belongs to an inner and invisible sphere 
 of action, the sphere of experience proper, where we have 
 actual certainty. The difference is concerned with different 
 sets of nerve apparatus, and different sets of muscles, the local 
 difference being considerably more marked when we compare 
 vocal expression with manual exercise in the use of a sharp- 
 edged tool, or in wielding a pen. The similarity consists in 
 the exercise of will power, which equally originates all three 
 actions. When we compare these three volitions, we can only 
 speak of them as successive acts of the same power. Eefer- 
 ence to local differences, such as is fitly made when we speak 
 of the action of nerves and muscles, entirely disappears as in- 
 applicable. These volitions are simple exercises of a power of 
 control over our organism which we find ourselves to possess. 
 So thorough and simple is this control, that it is possible, by 
 mere act of will, to use at the same time the organs of speech, 
 and the muscles of the arm and hand required for the act of 
 writing, or for use of a sharp-edged tool. The unifying power 
 which harmonises the action of nerves and muscles far apart is 
 the Will Power which governs both. How the Will exercises 
 this control over the cells, fibres, and muscular tissue is un- 
 known ; but that such control is exercised admits of no doubt ; 
 the result being normal action of nerve and muscle, according 
 to the purpose of the agent. What takes place within the 
 physiological sphere is a liberation of nerve energy, propagated 
 along the motor nerve, and communicating the impulse need- 
 ful for liberation of muscular energy, which thenceforth con- 
 tinues to work according to the Will's behest, and is instantly 
 stopped when the Will decides upon cessation of effort. The 
 
viii.] EXPERIENCE CONNECTED WITH MOTOR ACTIVITY. 251 
 
 truth illustrated by the large multitude of muscular acts 
 properly described as voluntary may be included under some 
 such formula as the following : — Man has the mastery of his 
 organism, so as to determine the use of its muscular energy in 
 the field of exercise appropriate to it, and within the limits 
 assigned to it. If in individual history this mastery be 
 abridged, as in cases of motor paralysis, disease has been 
 induced, and an abnormal condition established. But, accord- 
 ing to the constitution of our being, and consequently in 
 accordance with the laws which regulate the correlated activity 
 of thought, volition, nerve, and muscle, it is the normal condi- 
 tion of human existence that intelligent control can be easily 
 exercised over bodily movements. 
 
 On the ground to which this conclusion has brought us, we 
 are completely beyond the region within which that theory can 
 be applicable which relies exclusively on the action and reaction 
 of sensory and motor apparatus. The only hypothesis which 
 such a theory can present is this : that beyond the range of 
 sensori-motor activity there are still other correlated cells and 
 fibres by the action of which thought and volition are induced ; 
 that by some obscure and mysterious process the thought 
 cells become active; that these, by evolving intellectual 
 energy, propagate movement along an intellectual fibre ; that 
 this intellectual fibre communicates an impulse to a volitional 
 cell, causing it to evolve voluntary energy, propagating move- 
 ment along a volitional fibre; and that this volitional fibre 
 moves the motor cell by the action of which on the motor 
 nerve the muscle is set in motion. This is a hypothetical 
 scheme, constructed according to the analogy of the sensori- 
 motor system, and intended to embrace the wider range of facts 
 known as intellectual and volitional. It is supposed that such 
 a theory is favoured by the general acknowledgment that a 
 central governing power belongs to the frontal lobes in the 
 cerebrum, and also by the fact that the frontal and occipital 
 lobes yield no response to electric stimulation, while the 
 greater part of the central lobes, upper and under, yield a 
 ready response. This is the theory which must find favour 
 with those who believe that all human activity can be ex- 
 plained by " the irritation and contractility of animal tissue," 
 
252 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 or that " mind is a function of brain/' and it must be explicitly 
 accepted by those who are prepared for the very definite 
 declaration of Cabanis, that " the brain secretes thought as the 
 liver secretes bile." How far such a theory can bear the test 
 of facts, and specially how far it is compatible with our know- 
 ledge of will power, must now be considered. And here, it 
 must be observed, that human experience alone can afford the 
 test to be applied. Whether the lower animals exercise any 
 such control over their actions as we do, when we speak of 
 voluntary determination, there are no means of knowing. So, 
 far as the evidence afforded by their actions can be supposed 
 to bear on the question, there is little to favour the supposition 
 that rational self-determination belongs to them. The great 
 majority at least of their actions can be accounted for by 
 sensori-motor activity, and a very small margin is left for cases 
 which may be held to leave some room for doubt. With 
 human actions it is not, indeed, exactly the contrary, but the 
 distribution is so different that when we have excluded the 
 play of vital organs by means of the sympathetic system, only 
 the smaller proportion of human actions can be attributed to 
 purely sensori-motor activity; by far the greater proportion 
 give evidence of voluntary determination. The completeness 
 of this contrast occasions perplexity for any theory which seeks 
 to account for all forms of human conduct by the action and 
 reaction of sensory and motor nerves. 
 
 Considering the direction in which physiological inquiry 
 proceeds, by study of the cerebro-spinal system, it was inevit- 
 able that a theory reducing all human action to the play of 
 nerve force should be propounded. Such a hypothesis natur- 
 ally arises as one of the alternatives to be discussed. A real 
 service has, therefore, been rendered to scientific research in 
 the department of physiology, and also to mental philosophy, 
 by the attempt to include all forms of human activity under 
 the sweep of physiological law. Only by means of a clear and 
 certain rejection of such a theory on the ground of its insuffi- 
 ciency to account for the facts can there be a thoroughly in- 
 structed acceptance, under scientific and philosophic warrants, 
 of the theory that man possesses a higher order of life than 
 the physical, yet in entire harmony with his physical organism, 
 
 & 
 
vin.] EXPERIENCE CONNECTED WITH MOTOR ACTIVITY. 253 
 
 and so governing it that the two constitute a unity of being. 
 The question, then, is this — Is the exercise of Will Power as a 
 familiar fact in personal experience of such a nature that it 
 can he accounted for by a form of nerve action analogous to 
 sensory or motor activity ? Seeking an answer to this question 
 along the lines suggested by the nerve theory, we shall see 
 what claim that theory has to acceptance. Granting that much 
 uncertainty still hangs over the action of nerve cells, what 
 evidence is there to support the hypothesis that, there are 
 intellectual cells and volitional cells ? 
 
 1. There is neither anatomical nor physiological evidence in 
 support of the theory. There is clear anatomical evidence of 
 two orders of fibres, sensory and motor, each one of which is 
 directly connected with its own appropriate nerve cell; and 
 there is equally satisfactory evidence that, at least .in very 
 many cases, the two sets of cells are so connected together that 
 impulse can pass over from the one order of fibre to the other. 
 Physiological evidence is in strict harmony with the anatomical 
 evidence. (See above, Chapters III., IV., and V.) But there is 
 no proof presented either by anatomical or physiological re- 
 search of the existence of two additional orders of cells. There 
 is no scientific warrant for maintaining an intellectual-volitional 
 or volitional-intellectual order of fibres and cells within the 
 cerebro-spinal system. 
 
 2. The theory, though purely hypothetical, has the merit of 
 being formed in strict accordance with the analogies suggested 
 by the sensori-motor system. The sensory apparatus and the 
 motor, as they exemplify the law of action and reaction, 
 afford the scientific groundwork on which are arranged the 
 details of this hypothetical scheme of intellectual and volun- 
 tary activity. This must be acknowledged as a merit in a 
 scheme of thought which claims to be regarded as illustrating 
 " the scientific uses of imagination." But valuable as it is to 
 have a scientific ground-work to guide us in the exercise of 
 scientific inventiveness, it must be remembered that analogy 
 proves nothing. 
 
 3. The facts relied on as auxiliary to the theory do not in 
 reality support it. These facts are the admission of a general 
 governing power as belonging to the frontal lobes of the cere- 
 
254 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 brum ; and the absence of response from the frontal and occi- 
 pital lobes when electric influence is directed upon them. That 
 these two facts are clearly established by ample evidence 
 admits of no doubt. But that the frontal lobe has a governing 
 influence in nerve organism is a fact which may equally har- 
 monise with either theory, and proves nothing for either. On 
 the theory that the brain is the organ of the mind, by means of 
 which provision is made for the mind's government of bodily 
 movements, it is quite in harmony with this to say, that the 
 frontal lobe is the leading division of the central organ, by 
 means of which control is maintained. And so, on the other 
 hand, if brain explain all, the frontal lobe may well be the 
 sphere of central government within the brain proper. This 
 fact makes nothing for either side. 
 
 Again, it is true that the frontal and occipital lobes are 
 silent when the electrodes are directed upon them (see p. 117). 
 While stimulation of the central portions of the brain proper 
 leads immediately to distinct movements, there is no such re- 
 sponse when the portions of the organ to the front and back 
 are subjected to test. For the theory which finds the origin of 
 all human activity within the cerebro-spinal system, there is 
 some advantage here. These " silent regions " present a con- 
 siderable unexplored territory, and so afford "locality," an 
 element essential for such a theory. These " blanks " within 
 the organism can be filled up with imaginary apparatus for in- 
 tellectual and volitional activity. Only, this may be done as 
 a draftsman can fill in a plan with villas and gardens which 
 never had any existence. No scientific value can belong to 
 such imaginative exercise. While "locality" is there, and 
 it is an advantage to the theory that the frontal region is a 
 part of that locality, these regions are silent in the brains of 
 lower animals, such as the dog and cat, and it is the observa- 
 tion of their silence in such brains, not in the human brain, 
 which has given rise to this speculation. This fact is un- 
 favourable to the theory. There is inherent weakness in the 
 argument which seeks help towards discovery of the key to 
 the intelligent self-direction of human life, in the fact that 
 there are certain regions in the brains of animals greatly inferior 
 in intelligence of which nothing can be made by the most per- 
 
Viii.] EXPERIENCE CONNECTED WITH MOTOR ACTIVITY. 255 
 
 severing use of electric stimulus. The perplexity is increased 
 when we add the fact that, as we descend the scale of animal 
 life, including animals of greatly inferior intelligence, the pro- 
 portion of area yielding no response to electric stimulus is still 
 larger. Dr. Terrier records the results of his own observations 
 in the following terms : — " The brain of the pigeon, as well as of 
 the common fowl, on which I have also made experiments, 
 though apparently constructed on the same type as the brain 
 of rodents, differs from these in the fact that electrical irritation 
 fails to excite analogous movements." 1 The "locality" re- 
 maining silent under the electrodes, and still requiring to have 
 its functions determined, is seen extending before the view, 
 but in the wrong direction, that is, down the scale of life and 
 further away from intelligent self-control. On the other hand, 
 a great amount of sensory and motor activity remains to be 
 accounted for beyond the forms of action illustrated by electric 
 stimulus, and the " silent regions " are largely needed to give 
 room for the requisite nerve action. 
 
 4. The facts to be explained, — voluntary control of muscular 
 activity under guidance of intelligence, — do not manifest re- 
 semblance to the known facts of nerve action, but present a 
 decided contrast. To attain some reasonable degree of plausi- 
 bility, the theory which allows only for action and reaction of 
 animal tissue in human life must make out some degree of 
 resemblance between the facts of nerve sensibility and nerve 
 stimulus of muscular fibre, and the other set of facts, namely, 
 intelligent deliberation as to means and ends, and consequent 
 personal determination to put to use the muscular energy at 
 command. But this the theory fails to do. Besemblance be- 
 tween the facts there is not ; and in place of what is required 
 by the theory in order to make good its claim to existence, 
 there is a thorough-going contrast between the two sets of facts. 
 The action of sensory and of motor apparatus is instantaneous 
 and uniform under the normal conditions of activity; under the 
 different conditions which apply to thought and volition, there 
 are such successive stages in experience as suspense, delibera- 
 tion, and determination. If the artificer work from a plan set 
 before him, it cannot be said that his workmanship is explained 
 
 1 Ferrier's Functions of the Brain, p. 159. 
 
256 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 by the impression which the light reflected from the surface of 
 the plan makes on his retina, the transmission of influence along 
 the optic nerve, the action upon the sensory cell, and the trans- 
 mission of influence to all the motor cells concerned with the 
 control of the muscles brought into exercise. If apparatus can 
 provide for such work, we need more of it than the sensory and 
 motor. We have such experience of what is involved in these 
 cases, that we know there is a series of personal actions essen- 
 tially connected with the work, and which are not included in 
 the description just given. There is comparison of different 
 parts of the plan, in order to gain an intelligent appreciation 
 of it as a whole. And it is only when such a conception is 
 obtained, that the craftsman attempts the task of realising 
 by his handicraft what is present as a conception in his mind. 
 So far is the conception of the plan from being a mere 
 mechanical result consequent on the impression made upon 
 the retina, that each workman has his own conception, — the 
 beginner having a much less adequate conception than the 
 experienced artificer. This difference of conception is in some 
 degree dependent on the greater facility in the use of his 
 powers of observation possessed by the experienced workman. 
 But the chief part of the explanation is to be found elsewhere. 
 It is found in the power of discrimination vested in an intelli- 
 gent nature, and which, in the previous chapter, has been 
 shown to be characteristic of man's use of the sensory appar- 
 atus. Hence the man of larger experience may be slower to 
 begin his work than an inexperienced workman. And this 
 suspension of muscular effort is the result of his own exercise 
 of Will power. He deliberately holds in abeyance his muscular 
 energy, in order that he may use to full advantage his power 
 of intelligence. The distinctive feature of volition, as the 
 exercise of a power of self-control, appears equally in the 
 suspension of muscular effort, and in the direction of intel- 
 lectual. The difference between a skilful and an unskilful 
 workman may be variously expressed. We may say of the 
 two men, each man sees only what he has the eye to see, 
 or the one has not head enough, or perhaps has not brains 
 enough, to recognise or attempt what the other does. But, 
 when we test our meaning, we find that what is really intended 
 
VIII.] EXPERIENCE CONNECTED WITH MOTOR ACTIVITY. 257 
 
 is that there is higher intellectual work in the one case than in 
 the other. And this intellectual action illustrates a higher 
 exercise of Will power, namely, that kind of control which a 
 man is capable of wielding over his own Intelligence. Any 
 diversity of intellectual power between the two men does not 
 obscure the distinctive place of volition. The difference of 
 work in the two cases is not necessarily the result of higher 
 intellectual gifts in the skilled workman than in the unskilled. 
 Tor the beginner, as yet so unfit to make full use of his 
 power, may as the result of discipline and study prove himself 
 able to surpass the man who was vastly his superior at an 
 earlier stage. But such discipline and study imply continu- 
 ous exercise of Will power, controlling sometimes purely 
 intellectual effort, sometimes muscular effort so as to attain the 
 manual dexterity needful for the outward expression of what 
 lives in the mind. Will power finds exercise where intelligence 
 operates, for volition is rational determination, in contrast with 
 a mere sensory or motor impulse. It is in the midst of intel- 
 lectual exercises, in the realm of Mind proper, that we find the 
 seat of central government exercised by Will. And yet, though 
 there is a difference, amounting to duality of being, between the 
 intellectual and the physical, there is such harmony of the two, 
 such unity by means of duality, that Will governs both with 
 equal facility, directing the muscles in their work, as readily as 
 the intellect in its reflection by means of deliberate exclusion 
 of extraneous topics. The intellectual and the physical nature 
 constitute one being, and Will directs the action proper to both 
 elements of the one life. While, however, these two thus really 
 constitute one being, and the unity is apparent in the unity of 
 controlling power which the Will exercises over them, the 
 two natures are so distinct that muscular power can be 
 kept in a state of inactivity, while the intellectual nature 
 is busily occupied. Yet the converse is not possible in the 
 doing of any skilled work, for the intellectual nature cannot 
 be left inactive while muscular activity proceeds. On the 
 contrary, intellectual action is continually needed while the 
 acquired manual dexterity is brought into requisition. The 
 Will governs the muscular activity by means of intellectual 
 insight determining the work to be done by the hands. Thus 
 
 K 
 
258 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 the Will is a power controlling the whole being, intellectual and 
 physical, but a power which has its seat, and the source of all 
 its dominion, in the mental or intellectual sphere. Human life 
 is not governed by the action and reaction of sensory and 
 motor apparatus. Its government is from an inner and higher 
 sphere, within which the higher powers of man operate so 
 freely, that the true personality of the man is seen in the 
 voluntary exercise of the intellectual nature. Whether there is 
 activity of the nerve cells while the artificer is merely ponder- 
 ing his plan there is no evidence to show ; that there is a large 
 amount of work done by the nerve cells while he is engaged 
 with his manual effort we have clear and abundant evidence to 
 prove, — evidence not drawn from any experience we have in 
 such cases, but obtained by physiological research. Eestricting 
 attention first to physiological evidence, the position is this — 
 absence of evidence in the one case, abundant evidence in the 
 other. Turning next to the facts of experience, we know cer- 
 tainly that by exercise of Will we set the muscles into action 
 for the accomplishment of work, and we voluntarily stop their 
 activity. In like manner, we know that by the same Will 
 power we govern our thoughts. Further, we know that this 
 Will power is essentially connected with our intellectual nature, 
 as a discriminating or seeing power, insomuch that the volun- 
 tary direction of muscular activity is intellectual direction of 
 it, and intellectual direction is voluntary. Putting the case 
 most guardedly, there is no evidence that nerve action produces 
 volition; there is clear evidence that volition controls nerve 
 action. When this control is examined, it is found to be some- 
 thing more than mere determination of nerve action by com- 
 munication of impulse, such as occurs when an external object 
 comes into contact with a sensory nerve. There is communi- 
 cation of impulse to the motor cell in some way unknown to 
 us; but there is in addition, what is not fouud in sensory 
 activity under tactile impression, or in reflex activity of the 
 motor system, discrimination of possible forms of action, and 
 determination of a particular line of action by personal purpose, 
 on intelligible grounds, and for attainment of a selected end. 
 
 Thus we recognise in personal activity a ruling feature, most 
 conspicuous in human life, which stands in complete contrast 
 
viii.] EXPERIENCE CONNECTED WITH MOTOR ACTIVITY. 259 
 
 with all that is known of nerve action, and consequent mus- 
 cular activity. In obedience to volition, the motor impulse 
 goes from the motor cell, just as the sensory impulse goes 
 instantaneously from the touch-corpuscle after tactile impres- 
 sion. But before the volition there was suspension of all 
 muscular action, — there was voluntary reflection, turning first 
 in one direction, then in another ; as the result of comparing 
 these different lines of thought, there was the formation of a 
 definite resolution as to how to act, and the volition to use the 
 muscular energy came later, as the result of all this prior in- 
 tellectual and voluntary activity, which gave no visible tokens 
 of its procedure, save the expression on a preoccupied face. 
 All this prior action, with its double aspect of Intelligence and 
 Will, is entirely different from the instantaneous and perfectly 
 uniform play of nerve energy under appropriate excitation. 
 This conclusion may be most strikingly confirmed by detailed 
 reference to the work of the artificer or higher artist, who 
 works, not from a plan or copy presented to his eye, but from 
 an ideal conception which has no existence save in his own 
 mind ; but there is no need that this wider course of evidence 
 should be added to confirm what the lower and more ordinary 
 forms of action clearly establish. 
 
 Having now some definite account of what is meant by self- 
 control of our whole nature, as illustrated by muscular action, 
 we are in a position to remark upon the distinction adopted 
 in physiology between " voluntary muscles " and " involuntary 
 muscles," previously mentioned (p. 45). Distinguishing be- 
 tween the action of the sympathetic system and of the cerebro- 
 spinal system, it is not unnatural to introduce a reference to 
 volition as pointing to some ground of distinction. But it 
 needs to be observed what this distinction really is, and how 
 much it involves as illustrating certain characteristics of human 
 life. ' We speak of voluntary and involuntary actions ; but 
 while this is in point of form a classification of actions, it really 
 amounts to a double use of the word " action." In the one case 
 the type of activity involves the action of the whole being, — the 
 man as man acts. In the other case it is not so ; the type of 
 activity is not an action of the whole being, — the man as man 
 does not act. We speak of the action of the heart, or of the 
 
260 7W£ RELATIONS OF MIND AND BRAIN. [chap. 
 
 lungs, but this is a mere organic act, — a spontaneous move- 
 ment of a vital organ, requisite for physical existence. It is 
 movement rather than action, — the movement of vital organism, 
 characteristic of all animal life. It is essential to animal life, 
 but is not characteristic of the higher, self-regulated life of 
 man; it is not, in any proper sense, a human action. It is 
 as regularly performed in the life of the unconscious infant as 
 in mature life; in sleep, as in waking hours; in the uncon- 
 scious state induced by chloroform, as in the hours of active 
 exercise. If, from such actions, we pass over to muscles 
 named "voluntary muscles," can we describe all their "actions" 
 as " voluntary actions " ? We can not. Prick a man's hand, 
 and it is instantly withdrawn, — that is involuntary. The man 
 stretches out his hand to lift a book from the table, — that is 
 voluntary. What is the difference ? In the first case, the 
 man as man does not act. Sensibility of nerve fibre is 
 sufficient to account for all that is involved. In the second 
 case, the muscular action is as simple as in the first, but the 
 man as man acts, — there is intelligence and personal purpose 
 in the action. It is not the result of sensory stimulus, or of 
 physical craving, or of irritation operating within any part of 
 the organism. Simple as the action is, it illustrates a higher 
 phase of life, an exercise of control, which is not a uniform 
 characteristic of animal life. Thus the distinction to be drawn 
 between two different phases of action (which are never- 
 theless accomplished by the use of exactly the same nerve 
 appliances), introduces us to the difference between a lower and 
 a higher phase of life, and points directly to the pre-eminence 
 of man, as he is capable of intellectual and voluntary activity. 
 To speak of a sheep grazing, or a dog hunting, or a horse run- 
 ning in a carriage, as illustrating voluntary action is a mis- 
 application of terms. It is to confound things which differ, — 
 to mix up in confusion things lower and higher. Scientific 
 interpretation of such activity requires that a distinction be 
 drawn between such actions of the sheep, dog, and horse, and 
 the action of the man skilled in some handicraft. Keflex 
 activity will account for breathing and walking, but only in- 
 telligent, voluntary self-direction can account for the work- 
 manship of the artificer. 
 
VIII.] EXPERIENCE CONNECTED WITH MOTOR ACTIVITY. 261 
 
 One thing more must here be remarked in order to complete 
 the view of muscular activity in man. Under dominion of 
 Intelligence and Will, facility in muscular action is attained, 
 by means of which the demands of physical energy on the 
 higher nature of man are abated, and the possibilities of 
 intellectual action are increased. This introduces an addi- 
 tional element connected with manual skill. The work which 
 has first to be done slowly, and with careful direction of 
 the hand, and even of the separate fingers, becomes easier. 
 So it is with the artificer, with the musician, with the artist, 
 and in general with every one who seeks to acquire skill in 
 manipulation. Skill means facility in doing work finely, — 
 ease of management, and fineness of result. This possibility 
 shows us'not only the man as man acting, but the whole man 
 coming to the best or highest type of effort attainable. It is 
 an illustration of self-directed intelligence gaining ascendency 
 over bodily powers. It is an example of the higher life bring- 
 ing down so much of its power into the midst of the sensory 
 and motor apparatus, and obtaining a lodgment for itself in 
 the very midst of mechanical contrivances. Efforts once slow 
 and irksome become rapid and delightful; aptitude becomes 
 established in the very midst of the tissues. All such results 
 illustrate the power of Mind over Body, — the dominion which 
 the Will of an intelligent being is capable of establishing 
 over a sensitive muscidar system. 
 
 With this examination of muscular activity, the present 
 division of the inquiry may be closed. Yet must it be remem- 
 bered that there is a much higher range of intellectual actions 
 than those concerned with the government of muscular power. 
 And all these remain to present difficulties for the theory 
 of action and reaction within the nerve system much greater 
 than any of those encountered in course of the study of the 
 laws of muscular activity. 
 
262 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 CHAPTEE IX. 
 
 RETENTIVENESS OF ACQUISITION — MEMORY. 
 
 In treating of the uses of the sensory nerves as instruments 
 for acquiring knowledge, it has been shown that memory is 
 essential for experience in distinguishing successive sensations 
 (p. 222). At the earlier stage of our inquiry, however, the 
 simple fact of knowledge received attention rather than the 
 increase of our acquisitions, resulting in stores of knowledge. 
 We must now briefly consider what additional light is thrown 
 on our activity, and the higher development of human nature, 
 by the possibilities and laws of acquisition. From this point 
 we carry forward with us a more complex conception of our 
 nature. This conception now embraces all that belongs to the 
 sensory apparatus, and to the motor apparatus of the nerve 
 system, which is the governing power over the body ; and all 
 that belongs to Intelligence and Will power as the governing 
 powers of a higher life, and thereby the true governing powers 
 of the whole life. 
 
 The question which now arises is this, — How far is human 
 life influenced by varied acquisitions ? how far is the nature 
 expanded and enriched by storing up the fruits of earlier 
 effort? We must now regard memory not merely as a con- 
 necting band or cementing power, giving unity to a series of 
 sensations, but a power performing an important part in the 
 very midst of that higher life where Intelligence and Will are 
 working out their best results. We must begin where physio- 
 logical laws operate, including all phases of acquisition which 
 come from use of the sensory and motor apparatus, but we 
 shall end where psychological laws find application, and the 
 higher efforts of intelligence and will supply the materials. 
 
 Keverting, for illustration, to the skill of the artificer, we are 
 brought into view of both physical and intellectual aptitudes, 
 
IX.] RETENTIVENESS OF ACQUISITION— MEMORY. 263 
 
 and have a double phase of acquisition presented. The true 
 source, of his skill is the intellectual action by which the manual 
 effort is guided. But the form of skill for which he is distin- 
 guished is concerned with a definite number of the nerves and 
 muscles, in the use of which an acquired facility has [been 
 attained. Take away the intellectual action, and the entire 
 result is wanting. Voluntary intellectual effort is the common 
 condition for attainment of all forms of skill. Disable the 
 muscles of the arm, and the active use of skill possessed be- 
 comes temporarily impossible; but restored muscular energy 
 shows that the aptitude belongs to hand and fingers just as 
 before. 
 
 In order to reach an exact theory of the laws of personal 
 acquisition, it is needful carefully to distinguish these two 
 features of skill. They present two distinct phases of acquisi- 
 tion, — the one connected with nerves and muscles, the other 
 with intelligence and will. There is " a memory " or retentive- 
 ness in both, in accordance with which it is clear that facts 
 point to a twofold theory of acquisition. Taking into account 
 the relations of the higher and lower forms of action belonging 
 to our nature, we observe a feature of retentiveness peculiar to 
 the intelligent nature, and another belonging to the physical 
 nature. These two can neither be identified nor separated in 
 any explanation of dexterity in muscular effort and manipula- 
 tion. I shall consider them in succession, rising from the lower 
 to the higher, afterwards contemplating the union and harmony 
 of the two as characteristics of one life. 
 
 There, is a physical acquisition, resulting in physical aptitudes. 
 Evidence of the familiar fact can be gathered in a multi- 
 tude of forms. There is no artistic attainment which does 
 not illustrate it. In every such case there is a real attain- 
 ment, a retentiveness of something acquired. The seat of the 
 acquisition is partly in the nerve system, partly in the mus- 
 cular, and is definitely restricted to the portion of the organism 
 concerned in the form of activity. In accordance with the fact 
 pointed out when treating of the nerve system (p. 56), repeated 
 use of any part of the motor apparatus leads to a gradual 
 increase of power. Consideration of the conditions under 
 which this increase proceeds will guide us to the laws which 
 
264 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 determine the retentiveness belonging to the nerve system, and 
 to the muscular system as controlled by it. 
 
 Though retentiveness, in that form to which we commonly 
 give the name of memory, is generally regarded as concerned 
 with knowledge, it will be noticed that that to which attention 
 is meanwhile turned is connected with activity rather than 
 receptiveness. Accordingly, it is the motor system rather than 
 the sensory which engages observation. It is outflow of energy 
 along the lines of motor nerve and connected muscular tissue 
 which we find leading us to a theory of retentiveness ; it is not 
 an inflow of knowledge. And yet this outflowing energy, with 
 all its attendant results, is so connected with the exercise of 
 intelligence that it will not be possible altogether to separate 
 the two in our study of the facts. Nevertheless, we are, in the 
 first instance, mainly concerned with a law of retentiveness 
 found operating in connection with certain forms of muscular 
 action. This prominence of the motor apparatus, as compared 
 with the sensory, is important and suggestive. There is, in- 
 deed, a degree of increase in sensibility as well as in the 
 efficiency of the motor apparatus. But the illustration of 
 retentiveness supplied by the sensory apparatus is much more 
 restricted, and, as I took occasion at an earlier stage to remark 
 (p. 55), such increased sensibility, acquired and retained, in- 
 volves much more than sensibility. It really much more 
 illustrates an acquisition by means of intellectual activity. 
 
 Eetentiveness as exemplified in the history of motor activity 
 is a real physical acquisition, resulting in greatly enlarged 
 physical aptitude. Analysis of the facts is sufficient to show 
 that the retentiveness attributed to the motor system involves 
 in the first aspect of it development of power possessed by the 
 motor apparatus. Fully expressed, it is development for which 
 there is natural capability, along with conservation of the 
 fruits of such development. This illustrates the contrast 
 between mere mechanism and vital organism. The machine 
 remains what it was when it was constructed, tending only to 
 deteriorate as the result of tear and wear. Living organism is 
 so far an example of mechanism that it also wears out ; but it 
 is so superior to mere mechanism that development is the law 
 of its existence. This law of life is characteristic of all life, 
 
ix.] RETENTIVENESS OF ACQUISITION— MEMORY. 265 
 
 and in its simpler applications the law governs human life, as 
 it does lower animal life. This law of development applies to 
 our life from its first stage onwards until the period of physical 
 decay is reached, when phenomena appear in human history 
 which cannot be attributed to any other form of life known to 
 us — a manifest decay of physical life with progress of a higher 
 life. There is with man, as with all animals, development 
 through a series of fixed periods. There is the embryonic 
 period, during which from a germinal beginning life is devel- 
 oped in vital relation with a higher life on which its existence 
 depends, until the maturity of embryonic life is reached, and 
 birth into an advanced stage of existence takes place. There 
 is the development of infant life, of childhood, and next of 
 manhood, and thereafter a fixed period of decline, involving the 
 contrast in human history to which reference has been made. 
 Now, in all these successive stages of development the results 
 are retained as essentially belonging to the life itself. If, as is 
 very commonly proposed from a physiological standpoint, we 
 describe the retentiveness of the physical nature as a phase of 
 memory — and it seems to me there is a sufficient analogy to 
 warrant the suggestion, and to afford to physiological theory 
 the advantage which the admission implies — it must be noticed 
 that the admission involves acknowledgment of embryonic 
 memory, and infantile memory, as well as the memory which 
 belongs to more advanced stages, when life develops through 
 the periods of childhood and youth to manhood or maturity. 
 This no doubt involves a vastly wider range of meaning for the 
 word " memory " than has commonly been attributed to it ; but 
 as it is granted that there is acquisition and retentiveness of 
 acquired results, we may admit a species of Physical Memory, 
 granting at the same time that the admission must impose 
 upon mental philosophy the requirement that it make good 
 a radical distinction between Memory Proper and a purely 
 physical acquisition. 
 
 Having regard to the demands for demonstration of a dis- 
 tinctly higher life than the physical, as these demands fall in 
 the present division of the subject, it is of consequence to give 
 some prominence to the lowest phases of acquisition and reten- 
 tiveness. In embryonic life there is acquisition derived from 
 
266 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 the life of the mother, leading to enlarged life of the embryo. 
 What is thus derived becomes an essential portion of the 
 slowly unfolding life which has its fixed period of existence 
 within the womb. When the child is born the full formed 
 bodily life which it possesses has been derived from the 
 maturer life of the mother. And now the child, beginning its 
 separate existence, makes its start in life with retentiveness of 
 all that the mother's life has communicated, that is, with 
 definite features of life fixed for it, constituting a phase of 
 individuality by which the child may be distinguished from 
 other children. And here two things come under attention, 
 which well deserve to be considered, involving not a few 
 perplexities. These are the two correlated facts — heredity and 
 retentiveness. A law of heredity applies to every form of living 
 organism born into the world. This fact brings all animal 
 life and human life as well within sweep of a common law. 
 And in close relation with this law of heredity comes a most 
 interesting phase of the law of retentiveness. A few references 
 to animal life will considerably aid illustration. Earlier stages 
 in this inquiry have shown the prominence to be assigned to 
 the dog in treating of questions of comparative physiology, and 
 there is no animal which more interestingly illustrates the law 
 of heredity. Within the one species there are so many distinct 
 orders, with marked diversities of nature, that each order 
 carries in its history a definite contribution to the general 
 ■evidence. The pointer, the retriever, the greyhound, and the 
 collie, all illustrate this in a most definite manner. Every 
 young dog, of whatever order, gives evidence of a retentiveness 
 of qualities transmitted to it in the line of its descent. If then 
 we take every phase of retentiveness as a kind of memory, the 
 young dog in a sense embodies in its own nature a memory of 
 its ancestors' achievements, and our modern discoveries in em- 
 bryology present us with a modification of Plato's doctrine of 
 reminiscence which Plato did not contemplate, 1 reminiscence 
 of what has been acquired in a prior state of existence. 
 
 What is illustrated in animal life also finds illustration in 
 human life. The child inherits from its parents certain cha- 
 racteristics which determine many phases of its life. The day 
 
 1 Meno, 86. 
 
ix.1 RETENTIVENESS OF ACQUISITION— MEMORY. 267 
 
 of its birth witnesses fixed forms of existence which have been 
 gradually developed during the embryonic stage. This young 
 life, sensitive to surrounding influences, yet unconscious of its 
 own being, has not only the common characteristics of the race, 
 but inherited specialities which mark its parentage. This is 
 the earliest stage of retentiveness. And this is followed by 
 another stage in which the same law applies. The progress of 
 infant life is progress in development, connected with which 
 there is further exemplification of the retentiveness which 
 belongs to organism. "What is acquired in course of develop- 
 ment is retained. A stage further in advance 'we have the 
 tokens of the opening of a higher life, aided not merely by 
 sight, and smell, and touch, but by discrimination and infer- 
 ence, and aided by language, conveying instruction to a nature 
 fitted to receive and retain it. Here we find evidence of a 
 higher phase of memory, a retentiveness of a new order, which 
 has as a distinctive feature an imperfection in the retentive 
 power nowhere found in animal tissue. Now, in contrast with 
 earlier stages, things acquired in the course of development are 
 not invariably retained. Eetentiveness takes place under a 
 new law. As it passes into a new and higher phase it becomes 
 a more difficult exercise — indeed a new exercise, introducing 
 a higher law of progress than appears in lower orders, or at 
 lower stages in human existence itself. There is now a process 
 adapted for retention, — "laws of memory," — which can be 
 recognised by us as applicable in the case, by voluntary com- 
 pliance with which we can acquire knowledge, adding to stores 
 already in our possession. The true significance of this new 
 phase of retentiveness is seen by reference both to the difficulty 
 and the facility of retaining knowledge. 
 
 There is in this case a difficulty in acquiring which needs to 
 be encountered and mastered. Lower forms of acquisition 
 proceed according to a law which simply illustrates spontane- 
 ous development under favourable external conditions. There 
 is acquisition without choice, and without any effort save what 
 is common to all animal life from birth, in the reception of 
 food, with the amount of sensory and motor activity involved 
 in the search for it. But in the higher phase of activity now 
 under consideration it is a new order of food which is sought, — 
 
268 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 food for a higher life, — and the conditions of acquisition and 
 retention are changed. Besides, these new conditions or laws 
 apply to a much more advanced stage in the course of activity. 
 There is here a marked contrast hetween the activity of 
 animal life in obtaining food, — a form of acquisition which 
 affords the key to the greater amount of all animal activity, — 
 and the action of a higher life appropriate to the acquisition of 
 food for its own sustenance and satisfaction. In the animal 
 economy, if the food only be found and appropriated, the pro- 
 cess of assimilation goes on spontaneously by chemical action 
 within the organism, and all that is received is retained, save 
 inappropriate material, which is separated and carried off. 
 But the action of the higher life proceeds according to laws 
 entirely different. To acquire knowledge and to acquire food 
 do indeed involve to a certain point analogous effort, search, 
 and appi'opriation. Betentiveness in the two cases differs so 
 thoroughly that in the one case it implies effort, in the other 
 no effort. The two characteristics are illustrated in human 
 life, the one by mental life, the other by animal. In the 
 higher, retentiveness requires personal effort; in the lower, 
 retentiveness is inevitable, unless there be some derangement 
 of health, — some disturbance of natural action of the vital 
 organs. The contrast is notorious and familiar from the very 
 earliest stages of education in the life of a child. Lessons in 
 the alphabet introduce a marked distinction between the hour 
 for instruction and the hour for dinner. There are, indeed, in 
 the history of the lower animals examples of difficulty in 
 acquiring and retaining. But these are not connected with 
 the life in its natural state. It is not in running, or leaping, 
 or gamboling, or eating that any difficulty is experienced. 
 But if you would train a dog to ring a bell, lift a latch, or 
 walk on its hind legs in a semi-erect posture, the thing can 
 be accomplished only by slow, irksome, and repeated efforts. 
 These things will not be attempted by the dog spontaneously. 
 The design must come from without, and the determinations 
 to continue the effort must also come on each occasion from 
 beyond the ordinary range of organic impulses. The difficulty 
 comes from want of anatomical adaptation for the work to be 
 done, and the want of natural impulse to its execution. If 
 
ix.] RETENTIVENESS OF ACQUISITION— MEMORY. 269 
 
 the effort be sufficiently long continued there is in the 
 nerve and muscular system a law of retentiveness which will 
 induce greater aptness, or, we should rather say, diminish 
 the awkwardness and disagreeableness experienced by the 
 dog in walking on the two hind legs. There is a law of 
 retentiveness in every living organism which provides for 
 as much as this, so that training to do what is unnatural is 
 a possible thing under our management of the lower animals. 
 But when the singular movement has been acquired, the dog 
 does not spontaneously take to the exercise. However long 
 we keep on with the training, the animal does not itself begin 
 practising. If it be left to itself, by neglect of practice it soon 
 loses the accomplishment. But the difficulty of men in 
 acquiring knowledge is of a quite different order. There is 
 nothing constrained and unnatural in the effort. But there is 
 a new order of law introduced, and the distinctive feature in 
 the case is that we must voluntarily apply the law — that is, we 
 must recognise the law as the condition of attainment, and 
 must apply it with the special end in view. Take the two 
 familiar laws of Memory, — attention and repetition ; and the 
 distinction between mental action and the action of nerve and 
 muscle is at once apparent. That distinction is all the more 
 striking that there is an application in a modified and restricted 
 sense of both attention and repetition in training an animal. 
 Whoever would train an animal to such acquirement as that 
 described must command its attention, and constrain it to 
 repeat the irksome effort. There is enough analogy between 
 these facts and those of child life to account for less or more 
 of similar constraint employed in the earlier stages of human 
 life. But effort here is soon aided by intellectual interest or 
 curiosity, which seeks for gratification in the direction in which 
 the teacher is guiding. The sight of a class of children under 
 the management of a competent teacher sufficiently illustrates 
 this. It is indeed true, whatever interest be thrown around 
 the subject taught, that learning is a task, and tasking any 
 power, bodily or mental, implies effort, and effort may become 
 irksome. But the essential difference between the animal and 
 the child in meeting the demand for effort, is that the one does 
 not voluntarily take to the task, whereas the other does volun- 
 
270 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 tarily apply the law of attention and repetition. Learning 
 is a self-discipline. There is deliberate concentration on the 
 subject, and return over the ground, in order to make sure that 
 the lesson has been acquired. When this has been done, 
 something entirely different is accomplished from estab- 
 lishing facility in nerve action, and aptness in muscular 
 activity. A broad line of demarcation separates the mode in 
 which skill is acquired in the gymnasium, from that by which 
 knowledge is acquired in the school. The two things are not 
 on the same line. Knowledge of geography is not an attain- 
 ment only a little further on than gymnastic exercise. The 
 physical exercise may, indeed, contribute to the readiness and 
 energy with which one takes to mental effort. But it is the 
 contribution of an auxiliary, playing a very subordinate part, 
 when a new and higher power comes into action. Contrast 
 appears in this, that all through life a definite amount of 
 physical exercise must be taken, along with persistent and 
 concentrated study. But the one involves no progress, the 
 other implies advance to heights of attainment not even within 
 sight of the student at the earlier stages of life. Physical 
 exercise may be continued until the effects of failing physical 
 energy are very apparent ; and at the very same period of life 
 intellectual acquirements may be accumulated and retained 
 more rapidly than before. There is an illustration of voluntary 
 determination on both lines. Even when there is less aptness 
 for physical exercise, it is continued, because of the importance 
 which the student assigns to the laws of physical health ; and 
 even with the consciousness of greater aptness for acquisition 
 of knowledge, and greater delight in it, there is still voluntary 
 concentration, and exercise of mind dwelling upon the phases 
 and relations of facts brought under attention. There is volun- 
 tary application of the laws of attention and repetition, that 
 there may be retention, reproduction, and representation of the 
 acquired knowledge, in accordance with the threefold aspect of 
 memory admirably brought out in the analysis of Sir William 
 Hamilton. 1 
 
 A stronger light still is thrown upon the distinction between 
 the retentiveness belonging to vital tissue and that which is 
 
 1 Metaphysial, vol. ii. p. 205. 
 
IX.] RETENTIVENESS OF ACQUISITION— MEMORY. 271 
 
 connected with intellectual exercise, when we notice the con- 
 trasts between the two forms of facility. Skill in execution, 
 and facility in acquiring fresh knowledge, amply illustrate the 
 difference. Facility of manipulation becomes fixed in the 
 muscles, nerve fibres, and nerve cells. The right hand has 
 acquired a cunning so marked, that you cannot witness the 
 first movements of the hand on the part of a skilled performer 
 on a musical instrument, or of one who has skill in the use of 
 any implement, without noticing that the muscular movements 
 indicate aptness belonging to the tissue itself. The preliminary 
 run of the right hand over the key-board of a piano, before 
 the performer begins in earnest the piece of music to be per- 
 formed, is an indication of a muscular sensibility connected 
 with the use of the acquired skill. So certainly is there 
 facility of a nervo-muscular type that many of these acquired 
 actions can be done quite readily by a person while asleep. 
 The law of mental acquisition applies in the opposite direc- 
 tion. Facility in acquiring knowledge, diminishes the effort, 
 but does not abate the demand on attention. The performer 
 at the piano, or the artist working at some portion of his 
 picture, may speak with you on some subject quite apart from 
 his more immediate engagement. But the person busy 
 acquiring a language, or seeking to lodge in his mind minute 
 details of scientific classification, cannot do this. Hence also 
 the difference in after use of what has been acquired. The 
 skilful performer or experienced artist wants only his key- 
 board before him, or his brush in hand, in order to put into 
 exercise a facility of manipulation which he cannot explain. 
 But if one want to recall a word which has escaped his 
 memory, or a poetic passage, or a scientific distinction, it is 
 altogether otherwise. The possession is not stirring at the tips 
 of the fingers, or moving among the nerve cells eager for 
 egress. The laws of association, accepted universally as laws 
 of memory, imply the contrary, for they can be used to aid us 
 in a search, which, after some time and effort, will help us to 
 alight on the possession we want to recall for immediate use. 
 There is nothing in the working of vital tissue at all analogous 
 to this. These laws of association are so powerful that, within 
 the realm of mind, they are sufficient to account for involuntary 
 
272 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 recollections, but they are primarily and essentially instru- 
 ments for the use of a voluntary intelligence. Things similar, 
 things dissimilar, and things contiguous or brought into 
 affinity, become so connected in our intelligence, that they 
 tend to suggest each other. 1 What then is involved in the 
 application of these laws ? Voluntary intellectual exercise, 
 and that carried with deliberation and care into minute details. 
 There is observation of resemblances, of differences, and of rela- 
 tions as an introductory requirement before these laws of 
 association can become to any great extent influential in the 
 history of mind. The extent to which this prerequisite, in the 
 form of intellectual discrimination, has been carried, makes all 
 the difference between individuals in respect of the stores of 
 knowledge they possess, and accounts for the pre-eminence 
 which belongs in this region to the man of science. 
 
 Professor Bain has ventured upon a hypothesis as to reten- 
 tiveness of our knowledge in the substance of the brain itself. 
 He suggests "the possibility of storing up in three pounds' 
 weight of a fatty and albuminous tissue done into fine threads 
 and corpuscles, all those complicated groupings that make our 
 natural and acquired aptitudes and all our knowledge." 2 
 What has just been said affords materials for testing such a 
 hypothesis. Most important for this purpose is the broad 
 contrast between physical aptitudes and retention of know- 
 ledge in accordance with laws of a character quite different 
 from those which determine results in the nerve and muscular 
 system. 
 
 The most important part in the hypothesis is contained in 
 the following statement, that "renewed feeling occupies the 
 very same parts, and in the same manner as the original feel- 
 ing, and no other parts, nor in any other manner that can be 
 assigned." It is an interesting and not improbable suggestion 
 that this may be true in the history of brain action, in so far 
 as impressions on brain through the sensory apparatus are con- 
 cerned. I incline to think the hypothesis in this restricted 
 form highly probable. But everything which makes it pro- 
 
 i Hamilton's Metaphysics, vol. ii. p. 233. Mill's Examination of Hamilton's 
 Philosophy, p. 219. 
 
 2 Mind and Body, p. 89. 
 
IX.] RETENTIVENESS OF ACQUISITION— MEMORY. 273 
 
 bable in connection with the recalling of sensations, seems to 
 me to make it improbable as bearing upon the more advanced 
 forms of intellectual exercise. Since sensibility at the peri- 
 phery implies movement of the nerve cell, it seems not at all 
 unlikely, that when a particular sensation of colour, or light, 
 or heat, or sound is remembered, some distinct movement of 
 the nerve cell belonging to the sensory nerve concerned may 
 take place. This is supported by well-known facts as to the 
 power of the imagination in acting upon the nerve system, 
 inducing agitation which has no external explanation. It is 
 quite supposable, and in keeping with such analogy, that the 
 recollection is aided, and in part sustained, by movement in 
 the appropriate nerve cell. But this does not account for the 
 fact of recollection. Let us suppose that when a man recalls a 
 sensation of sweetness, there is in the brain some movement 
 in the cellular matter related to the sensory fibres coming 
 from the tongue and palate. The manner in which the organs 
 of taste can be affected, so as to act upon the salivary gland, 
 even by the imagination alone when directed upon favourite 
 articles of food, lends considerable support to this view. But 
 the essential question is, — What accounts for the fact of recol- 
 lection ? Whenever the organism is acted upon from without, 
 as by the sight of ripe fruit or other article pleasing to the 
 palate, it is comparatively easy to find the explanation. The 
 impression made on the optic nerve may, by established co- 
 ordination within the brain, act .upon the sensory cells con- 
 nected with the fibres coming from the mouth, and the 
 movement so induced may be propagated along the connected 
 fibres, producing that result known to us as " teeth-watering," 
 and which may be not unreasonably described as a reminiscence 
 of taste. If a fresh sensory impression in any degree stir the 
 cells belonging to the sensory apparatus, we have in the new 
 impression what accounts for the rise of recollection. But if 
 there be no impulse from without, how shall we explain the 
 fact of recollection ? It cannot be maintained that all recol- 
 lection is connected with new sensory impression. Nothing is 
 more obviously within our reach than the power of devoting 
 ourselves to the exercise of recalling the scenes and events of 
 early life. When so occupied, a person is readily charged 
 
 s 
 
274 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 with " absent-mindedness," and his look conveys the impres- 
 sion of remoteness from present influences. This exercise of 
 recollection may, indeed, be involuntarily started ; but it may 
 be voluntarily and quite deliberately undertaken, and this fact 
 is unexplained by the hypothesis. Again, it cannot be alleged 
 that the brain spontaneously begins to vibrate, so as to throw 
 a series of cells into excitement ; and that these cells, ringing 
 changes upon once familiar combinations, keep us in a tumult 
 of recollections. There are, indeed, recollections which may 
 be said to haunt the brain, and which gain a mastery over the 
 individual ; but such experience is unusual, and for the most 
 part abnormal. Human experience is not thus at the mercy 
 of recollection. Even if the nerve cell be vibrating while we 
 recall a particular sensation, what starts this vibration? If 
 we are to follow the analogy afforded by the nerve system, we 
 may say that as with the original impression the impulse came 
 from without, the revived impression must, in absence of 
 external influence, depend upon an impulse coming from 
 within. Professor Bain forcibly states his case in the following 
 sentences : — " If we suppose the sound of a bell striking the 
 ear, and then ceasing, there is a certain continuing impression 
 of a feebler kind, the idea or memory of the note of the bell ; 
 and it would take some very good reason to deter us from the 
 obvious inference that the continuing impression is the per- 
 sisting (though reduced) nerve-currents aroused by the original 
 shock. And if that be so with ideas surviving their originals, 
 the same is likely to be the case with ideas resuscitated from 
 the past — the remembrance of a former sound of the bell." The 
 suggestion is admirably put, though it seems unwarrantable to 
 speak of the " continuing impression " which attends on the 
 gradual cessation of the current as " an idea or memory " of that 
 of which it is still a part, — a continuance. What is wanted 
 is to account for the fact of the revival of the impression, and 
 this is not done. If sensations are " resuscitated from the 
 past," we need to ascertain how such resuscitation takes place ; 
 and it does not help us towards an explanation even if we allow 
 that " the renewed feeling occupies the very same parts, and in 
 the same manner as the original feeling." 
 
 There is, besides, an inconsistency in supposing that a nerve 
 
ix.] RETENTIVENESS OF ACQUISITION— MEMORY. 275 
 
 cell, or any number of such cells conjointly, can be not only 
 the seat of the renewed impression, but also can exercise both 
 a retentive power preserving some record of the past impres- 
 sion, and a reproductive power bringing it back to conscious- 
 ness. This difficulty is greatly increased if, while such functions 
 are attributed to a cell, it may in the interim be occupied with 
 other impressions. Previous investigations show that repeated 
 exercise of the same sensory or motor combinations, under 
 voluntary direction, will secure facility of exercise. A certain 
 impression is made on the tissue, which shows itself by the 
 subsequent facility in acting. But this facility is the result of 
 a continuous influence to which each successive instance of 
 voluntary use of the apparatus contributes. The result is not 
 a separate and separable record of single acts, but a cumulative 
 result, in which the quota contributed by each action or vibra- 
 tion of the apparatus is indistinguishable. We may not unrea- 
 sonably describe this as a kind of memory belonging to hiving 
 organism, for it holds good of animal tissue even where the 
 guidance of will comes into play. But there is in these facts 
 nothing analogous to what is here suggested ; nothing of that 
 form of exercise which is required of a memory retentive of 
 distinct acts, afterward to be recalled as distinct. If, in addi- 
 tion, we must suppose either that the Derve cells retain such a 
 record of a past impression, and all the while continue function- 
 ally active in the reception of fresh currents ; or that the nerve 
 fibre, after having acted upon one cell, selects another from 
 those still unoccupied, and so continues encroaching on an 
 available number of cells assigned to each sensory nerve, the 
 complications of the hypothesis become serious. Each alterna- 
 tive is beset by its own perplexities, which seem to me fatal to 
 its claims. The first is clearly untenable. No single cell or 
 small group of correlated cells, connected with a single sensory- 
 fibre, could keep on receiving fresh impressions sent along the 
 fibre, and also retain some record of those which have gone 
 before. The only feasible alternative is the second, and to that 
 accordingly Professor Bain gives the preference. But the 
 demand thereby made on cellular tissue transcends available 
 area to a degree far beyond what can be reckoned on the most 
 favourable supposition. There are very great difficulties in the 
 
276 THE RELATIONS OF MIND AND BRAIN, [chap. 
 
 way of supposing that the cerebrum — " three pounds weight of 
 a fatty and albuminous tissue" — is, in addition to all its other 
 functions, a storehouse of sensory impressions. We have seen 
 what a vast amount of work the brain has to do in providing 
 for the sensori-motor activity which is at least its primary 
 function. Every portion of the surface of the body has to be 
 maintained in a sensitive condition ; nerve currents have to be 
 received from all parts ; correlated action has to be propagated 
 between each sensory cell and a variety of motor centres ; and 
 nerve currents have to be directed upon any or all of the 
 motor nerves, in order to act upon the muscles, at the behest 
 of the will. Even if we claim no portion of the cerebrum for 
 purely intellectual action, and so considerably abate the diffi- 
 culties for a theory of cellular retention, the space available 
 for storing purposes cannot be large. When further we deduct 
 from the " three pounds weight " the whole mass of nerve 
 fibre in the centre, which is conducting fibre, requisite for the 
 ingress and egress of nerve currents, the want of storing-room 
 becomes a pressing difficulty. If every bell which sounds, and 
 every musical note we hear, and every word spoken to us, and 
 every object seen by us, and every act of tasting, and every 
 sense of odour, and every excitation of tactile fibres, lodges an 
 abiding impression on the cellular tissue, even though the 
 nerve cells were reckoned by millions, they would soon be 
 exhausted. Professor Bain takes the grey substance as equi- 
 valent to 300 square inches, and allows a " quarter of a million to 
 the square inch," — a very liberal calculation in each particular. 
 This reckoning does not sufficiently take into account the 
 differences known to exist between the outer and inner portions 
 of the grey substance, and the area appropriated for functions 
 quite distinct from retentiveness. In the outer layer of the 
 cortex, there is more neuroglia and less cellular substance. 1 
 The space appropriated for the sensory and motor functions 
 includes a great part of the mass of cellular tissue. Besides, 
 if we agree to deduct the vast range of intellectual operations, 
 assigning them to a higher nature, we still need distinct local 
 provision for all the forms of control over the organism re- 
 quisite for intelligent regulation of physical activity. Without 
 1 See above, p. 188. 
 
ix.] RETENTIVENESS OF ACQUISITION— MEMORY. Yfl 
 
 deduction for these demands, Professor Bain proceeds to 
 estimate the probable number of acquisitions, and the space 
 available for them. Eeckoning upon the whole area, he says : 
 " With a total of 50,000 Acquisitions of the assumed types, 
 evenly spread over the whole of the hemispheres, there would 
 be for each nervous grouping at the rate of 20,000 cells, and 
 100,000 fibres. With a total of 200,000 Acquisitions of the 
 assumed types, which would certainly include the most reten- 
 tive and most richly endowed minds, there would be for each 
 nervous grouping 5000 cells and 25,000 fibres." 1 In this cal- 
 culation the fibres, as connecting tissue, may be kept out of 
 account, except as representing an acquired facility in acting. 
 The calculation as to cells must, I think, be greatly modified, 
 the figures representing cells being greatly reduced, and those 
 representing Acquisitions greatly increased. On the one side, 
 it is impossible to proceed upon a calculation that apportions 
 the whole cellular substance for retention. On the other, 
 if retentiveness be a function of the cellular tissue con- 
 nected with all nerve activity, the extent to which the nerve 
 tracts are in use every day is such, that 50,000 would be 
 reckoned in the course of a few months of an ordinarily active 
 life. It may be that 200,000 acquisitions is a number suffi- 
 ciently large to embrace the whole acquirements of the best 
 endowed minds, — we are really without data to guide us here, 
 — but it would not nearly represent the number of nerve 
 vibrations bringing the apparatus into action. If we reckon 
 words alone, without counting the thousands of sensory im- 
 pressions experienced daily, Mr. G. P. Marsh says that " the 
 number of English words not yet obsolete, but found in 
 good authors, . . . does not probably fall short of one hundred 
 thousand." 2 These are not used by any one man. Shakespeare 
 is reckoned to have used 15,000 words, — Milton, in his poetical 
 works alone, 8000 ; but these do not include the inflections of 
 the same root. 3 What shall we make, however, of a case like 
 that of Cardinal Mezzofanti, who spoke fluently thirty lan- 
 guages ? 4 Professor Bain, in estimating the demands made 
 
 1 Mind and Body, p. 107. 2 Lects. on the English Language, p. 181. 
 
 3 Professor Masson's Essay on Milton's English, — Milton's Poetical Works, 
 j ; x _ 4 See infra, pp. 305-6. 
 
278 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 on the cellular mass in the cerebrum, assuming "an inde- 
 pendent nervous track for each separate acquisition," has not 
 allowed sufficiently for his subsequent statement in the follow- 
 ing sentences : — " It is not at all likely, however, that the 
 entire brain can be portioned equally among the various sub- 
 jects to be remembered or acquired. Besides the fact that a 
 great part of the brain substance exists for mere battery power 
 — to propel muscles, and to keep up energetic volitions and 
 manifestations of feeling — there seems often to be a duplication 
 of the same embodiment in different parts. 1 The two hemi- 
 spheres apparently repeat one another ; when one is injured, the 
 other keeps up the trains of memory, although with weakened 
 energies. It is even supposed that in the same hemisphere 
 there may be duplicates, since injuries in the forepart of the 
 head have occurred without destroying any single class of 
 acquisitions." 2 The grounds on which such acknowledgments 
 rest have been already presented. But important as these 
 statements are, Professor Bain has not prepared a' modification 
 of the figures in harmony with the admission's. When the 
 calculations have been adjusted, it will, I apprehend, appear 
 plain that there does not exist in the cerebrum cellular 
 substance sufficient to support a hypothesis that there is 
 " an independent nervous tract for each separate acquisition." 
 Under the hypothesis, it is impossible to restrict or select the 
 sensory impressions to be stored in the brain. If the retaining 
 of impressions is the result of functional activity, it follows that 
 every act of the sensory apparatus must find a nerve cell 
 within which to lodge a distinct and separate impression. This 
 appropriation of nerve cells becomes needful for renewal or 
 recalling of sensory experience, in order that the cellular activity 
 may occupy "the very same parts, and in the same manner as 
 the original feeling." On the conditions implied, there is no 
 possibility of limiting the number of impressions to be retained, 
 and so inquiry passes over to the available number of cells, 
 whither, indeed, Professor Bain directly "conducts it. Allowance 
 must, no doubt, be made for diversities in the power of im- 
 pression, and thus some place may be found for a theory of 
 organic " forgetfulness." A faint impression must produce a 
 1 For evidence of this, see above, p. ] 10. 2 76 p 108 
 
ix.] RETENTIVENESS OF ACQUISITION— MEMORY. 279 
 
 slighter effect on the cellular tissue than a vivid and powerful 
 one. But the henefit thus accruing to the hypothesis on the 
 one side is more than balanced by disadvantage on the other. 
 On the supposition before us, it would naturally follow that 
 louder sounds should be more effectually retained, by making 
 a more distinct impression on the nerve cells, than fainter 
 sounds. But if we refer for illustration to the words we hear, 
 we find it often otherwise. Words uttered in a subdued tone, 
 or even in a whisper, are better remembered by us than many 
 words uttered with great volume of sound. The law of reten- 
 tion in such a case is the reverse of what it should be, if it were 
 provided for by mechanical action of the sensory apparatus. 
 If a public speaker in the midst of an animated discourse, 
 were gradually to slow his rate of utterance, soften his tones, 
 and with all appearance of strong personal conviction, utter 
 some warning with subdued voice, that passage would be re- 
 membered more vividly than many others which have been 
 declaimed with animation, and great power of voice. The 
 deeper impression is dependent partly on sensibility, partly on 
 intelligence ; and the latter is the determining power as to 
 memory. The law of contrast does, indeed, apply in the region 
 of sensibility. For if " change of impression is necessary 
 to our being conscious," 1 a very marked change, as from 
 loud and rapid utterance to a slow subdued expression, is 
 clearly marked as something new, and arrests attention on 
 that account. It is narrated of a preacher who observed a 
 considerable number of persons in his audience fast asleep, 
 that he suddenly paused, and, having remained silent for some 
 minutes, he had the satisfaction of seeing all the sleepers wake 
 up to ascertain what had happened. There is not a very 
 high exercise of intelligence in such waking ; it is apt to be a 
 dawning intelligence, but it illustrates the fact that there may 
 be an impression from the very want of sensory impression, 
 observational power which takes account of contrasts. It is 
 intelligence in the hearers which mainly accounts for specially 
 vivid recollection of a passage delivered in slow and subdued 
 tones. But should the public speaker resort to such a mode 
 of address for utterance of a commonplace, the law of recollec- 
 
 1 Mind and Body, p. 43. 
 
280 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 tion is so far from being satisfied, that there will be no such 
 aptness in recalling the utterance, as otherwise would have 
 been experienced. Intelligence is the key to memory ; while 
 sensibility is the key to any retentiveness in tissue. There is 
 thus a broad contrast between two distinct phases of reten- 
 tiveness, each depending upon the application of different 
 laws. There is a memory which is entirely dependent on 
 discrimination and laws of association. Towards the explana- 
 tion of this the activity of sensory apparatus contributes only 
 a small share. There is a " memory " dependent on the simple 
 activity and sensibility of tissue, quite apart from intelligent 
 discrimination, under purely mechanical law. So far as mere 
 retentiveness is concerned, the physiological explanation of 
 this is complete. If we restrict attention exclusively to 
 the latter, we enormously reduce the demand upon the storing 
 room which the brain affords, and so add considerably to the 
 probabilities in favour of Professor Bain's theory ; but we do 
 so by holding completely in reserve all the main characteristics 
 of memory as commonly exercised by man. Even with this 
 sweeping restriction, however, I doubt if retentiveness of nerve 
 tissue, which is admittedly a fact, can receive such breadth of 
 interpretation as to warrant us in regarding it as a uniform 
 and constant law of nerve action. It is an interesting and 
 valuable suggestion that when we recall a sensory impression, 
 there is awakened some vibration in the very same part of the 
 tissue as was originally thrown into action by the impulse sent 
 from the periphery. But it is a much more perplexing and 
 less fruitful suggestion that the normal action of a sensory cell 
 involves retentiveness of impression, and that this retentiveness 
 is adequate to the task of reviving the feeling. The whole 
 body of ascertained truth included under the physiology of the 
 nerve system is against the supposition. The utmost which 
 ascertained results warrant is increased facility of action within 
 the nerve system, and an increased sensibility to sensory im- 
 pulse, which increases the power of external impulse. In this 
 way local associations, distinct from the organism, and standing 
 at the opposite extreme from the " laws of association," requir- 
 ing an exercise of intelligence for their application, act upon 
 an increasingly sensitive organism and present facts closely 
 
IX.] HETENTIVENESS OF ACQUISITION— MEMORY. 281 
 
 analogous to those of memory proper. Illustrations are so 
 numerous and familiar that I need not dwell upon them. 
 Whether this will account for the manifestations of memory 
 in the lower animals is not quite clear. So far as my observa- 
 tions have gone, I incline to think it does ; though I have 
 several times considered the results perplexing. Even a blind 
 horse becomes familiar with the road frequently travelled over. 
 One of the most striking facts I have observed in this relation 
 is afforded by a cat which has been for ten years a favourite in 
 my family circle. It is accustomed to lie on the hearth-rug, 
 sleeping in front of the fire. At the same hour each evening 
 it is lifted, and carried away to its quarters for the night. 
 Often when the door is opened, and it is approached at this 
 hour, and while the person is still some paces off, a slight 
 tremor is seen to pass over its body, and the animal wakes, 
 lifting up its head, and giving a slight purr, as the hand is 
 stretched towards it. The opening of the door has, I fancy, 
 something to do with it ; but I notice also a slight vibration of 
 the floor. These impressions, however, produce no . effect at 
 any other hour of the day. This is much more striking than 
 appears with the dog, which is simply called, and ready to run 
 at once. But in his case, the slightest sound produced by 
 opening or closing the biscuit-box makes him prick up his ears. 
 When the family are seated at table, it is not uncommon to 
 shut the lid cautiously, in order to avoid noise, and it is 
 astonishing how slight a sound will arouse him from sleep. 
 This cautious closing of the lid is in accordance with the 
 tactics adopted by the shepherds in a southern county of Scot- 
 land, who sat still in church while the benediction was being 
 pronounced, thereby " cheating the dogs," and preserving de- 
 corum, by delaying the sudden stretching of the limbs and 
 scampering along the lobbies. From such cases it seems fair 
 to conclude that nerve sensibility goes far to account for 
 manifestations of " memory " in the lower animals. In almost 
 all the examples I have seen, external influences clearly con- 
 tribute a part, by acting upon the sensory apparatus at the 
 time when revived feeling is apparent. 
 
 Increased sensibility, by frequent use of the same nerve 
 tracts, and a phase of retentiveness harmonising with the 
 
282 THE RELATIONS OF MJND AND BRAIN. [chap. 
 
 nature of the organism, are clearly established facts. They 
 seem, however, to lead no further than to the conclusion of 
 increased facility in cells and fibres, without contributing any- 
 thing towards a theory of particular memory. 
 
 There still remains, however, even on this theory, the one 
 essential point, How does resuscitation take place ? If it be at 
 the bidding of external impression, the nerve apparatus may 
 be competent for the work to be done, that being to rouse a 
 form of cellular activity. But there is nothing in the normal 
 action of the nerve system which fits it for originating sensory 
 activity within its own substance. The sensory cell is not 
 self-acting; it does not of itself originate sensation. It is 
 indeed possible that an excited and abnormal condition of a 
 sensory portion of the cellular tissue might awaken what we 
 should regard as equivalent to sensation. But this does not 
 favour the view that the sensory cell is a self-acting agent. 
 And if it be not, we need, in default of impulse from without, 
 impulse from an inner sphere of experience, where intellectual 
 activity proceeds under laws quite different from those which 
 apply in connection with purely sensory action. 
 
 Thus in attempting to account for the facts of memory, 
 familiar from early life, we pass the boundary into the region 
 where intelligent discrimination is a first requisite for remem- 
 bering. "Within this region the laws of association require 
 intelligence as essential for their application. Under these 
 conditions we exercise a particular memory or power of recall- 
 ing the exact combinations formerly recognised. There is 
 indeed here, as in the region where tissue alone operates, an 
 acquired facility, a facility in retaining, recalling, and repre- 
 senting things past ; but in this case facility is attained only 
 on condition of voluntary exercise of intelligence perseveringly 
 repeated. The effort to recollect gradually becomes less diffi- 
 cult, the task less irksome, and a pleasure is experienced in the 
 use of the gradually developed power. Thus the painfulness 
 of the task assigned in early life when memory-work is 
 imposed by authority disappears, and man uses his memory 
 as an important auxiliary in the sphere of intelligence. The 
 bond of union established by an exercise of intelligence may 
 become so strong as to lead to spontaneous recollection. But 
 
IX.] RETENTIVENESS OF ACQUISITION— MEMORY. 283 
 
 so much is this power of Memory under voluntary control, that 
 we voluntarily recall combined scenes and thoughts. Practice 
 in this department may be carried so far as to enable a speaker 
 to retain, and call up as required, a lengthened discourse. 
 And a still more striking example of the power of will in this 
 matter is shown by the fact that we may set ourselves to 
 banish from our memory what we feel it a duty to forget. 
 The task is difficult and irksome, requiring a higher degree 
 of self-control than our early efforts at recollection, and it is 
 attended by repeated sense of failure. But there is a possible 
 victory, — not by mere inaction of the memory, but by con- 
 flict with spontaneous activity of memory, and reconstruction 
 of a new class of associations, which shall take the place of 
 those dislodged. Mental associations are not indissoluble. 
 The power which constructs can break up the union. But a 
 voluntary forgetfulness is possible only by voluntary construc- 
 tion of new associations under guidance of intelligence. 
 
 Becollection following upon intelligent discrimination is an 
 essential characteristic of our experience. Such a power being 
 established, as distinct from acquired facilities of nerve action, 
 its importance as providing for attainment, and thereby for the 
 unfolding of a higher intellectual life, must be obvious. If 
 memory is needful for the simplest acts of discrimination as 
 we mark the points of contrast between successive sensations, 1 
 in a higher region of attainment, and at a point more advanced 
 in the history of mind, it becomes an essential requisite for 
 the development of our nature. It is by aid of this power of 
 Memory, storing up our acquirements as our study is continued, 
 recalling the lessons of a past experience as enabling us to 
 profit by past blunders, and making it possible for us to form 
 a conception of our entire life as a unity, that Intelligence and 
 "Will reach those heights of attainment which raise man im- 
 measurably above the possibilities of mere animal life. On 
 this aspect of the problem, Professor Hermann Lotze has written 
 with great clearness and force. After urging that in man's 
 life there is " freedom from the compulsion of mere mechanical 
 order," and a consequent impossibility of comparing physical 
 and mental processes, he says :— " As the decisive fact of 
 
 1 See above, p. 122. 
 
284 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 experience which compels us in the explanation of spiritual 
 life (des geistigen Lebens) to affirm in place of mere matter a 
 supersensuous being as the subject of the phenomena, we must 
 mark the unity of consciousness, without which the sum of 
 our inner conditions could not become the object of Self- 
 observation." l A knowledge of Personality we have, by 
 simple contrast of sensations ; a knowledge of Personal Iden- 
 tity, only by that higher exercise of Memory belonging to an 
 intelligent nature recognising the unity of our being through 
 widely separated periods of existence. 
 
 1 Mihrokosmus, i. 170. 
 
x l USE OF SPEECH. 285 
 
 CHAPTEE X. 
 
 USE OF SPEECH. 
 
 We have now seen that personality, known to each indi- 
 vidual as the essential characteristic of his own life, is self- 
 conscious, self-directed Intelligence. We have further seen 
 that the knowledge of personal identity is knowledge of the 
 unity of personal experience, as we recall events in our own life, 
 and manifold stores of knowledge accumulated during past 
 years. Personality is thus the central feature of human life, in 
 accordance with which each member of the race regards him- 
 self as a distinct being, possessed of powers all his own, and 
 hedged round by obligations which he must respect, and which 
 none but himself can fulfil ; karvgag within himself the govern- 
 ment not only of the organism which he calls InVown, but alscr 
 of his life as a whole, so as to determine what it shall be under 
 the discipline of events. 
 
 Having dealt with our acquisitions, both organic and intel- 
 lectual, I proceed now to contemplate Speech as an additional 
 fact prominent among the distinguishing features of human 
 life. If a Memory, operating within the sphere of Intelligence, 
 enables us to store up our acquisitions, the power of Speech, at 
 command of intelligence, provides not only for the outflow and 
 natural use of our acquisitions in influencing others, but gives 
 us the signal advantage of being quickened by their thoughts, 
 as organism cannot be quickened by other individual organisms 
 of the same species. 
 
 A power of vocalising, very restricted in its range, does 
 indeed belong to the lower animals, and affords a natural sub- 
 ject of consideration by way of introduction to this branch of 
 the main question. Each animal possessed of this power emits 
 its own special cry, and is capable of giving forth some grada- 
 tion of sound, the varieties in which are recognisable by others 
 
286 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 of the same species, producing, when heard, an effect analogous 
 to that which has occasioned their expression. This restricted 
 range of vocalisation is adapted to indications of fondness, fear, 
 and pain. There is commonly some form of sound employed 
 by animals expressive of fondness between male and female, 
 and between mother and her young. The mother commonly 
 calls for her young, and the young call for their mother. There 
 is besides an expression of fear at sight of danger, which serves 
 as a warning to those of the same species which are near. 
 Considering how constantly one race of animals preys upon 
 a lower order, this use of vocalising power fulfils, to a very 
 large degree, a protective function. There is besides, the more 
 acute and convulsive cry of pain, such as is uttered by the 
 animal which has fallen a victim to its captor. All these forms 
 of expression are connected with the exigencies of animal life. 
 They all depend on organic sensibility, excited either by organic 
 actions or by external influences. In the case of the ewe, in- 
 creased milk supply may incline her to seek her lamb, as the 
 sense of hunger may incline the lamb to seek the mother. In 
 either case, the famUJ£xbJpati]ig*<jxpresses organic feeling, and 
 4s~TrrtrcTr nrcTe'frequent when organic restlessness is induced, as 
 by separation of the lambs from their mothers. The expression 
 of fear is a direct result of impression made upon the organism, 
 as has been shown by experiments on rats, which are seen to 
 spring forward on each occasion of the utterance of a slight 
 sound in imitation of the movement of a cat. The cry of pain 
 is the uniform expression of the sense of acute suffering when 
 injury is inflicted on the organism. It is thus clear that in all ' 
 these cases we have examples of reflex action of the nerve 
 system by means of fibres connected with organs of vocalisa- 
 tion. There are powers of vocalisation which are acted upon 
 by sensory stimuli, as we have seen that on application of the 
 electrode to No. 9 on the brain of the dog (see p. 103), the 
 animal, though under chloroform, will be heard to bark. 
 Under ordinary conditions, such vocalisation must, therefore, 
 be reckoned as illustrating reflex activity. 
 
 Now, a child has this spontaneous power of vocalising. At- 
 tainment is not needful here, and is not aimed at as any part 
 of the child's training. Experiencing satisfaction or craving, 
 
X-] USE OF SPEECH. 287 
 
 the infant gives forth the sound natural to it. According as it 
 is actively employed with sense of satisfaction in the exercise, 
 or uneasy in its performance, it will be heard crowing or crying. 
 This in the early stage of human life is exactly analogous to 
 animal life. But when we come to consider articulate utter- 
 ance, we have something distinctive of man, for which we need 
 a higher explanation. The line of separation is reached when 
 discrimination begins, as a fact altogether in advance of sen- 
 sibility. Articulate utterance is the expression of intelligent 
 discrimination, not merely of diversity of sensible experience 
 under organic stimuli. If there be speech which is the 
 exponent of reflection, its use, regarded merely as a physical 
 manifestation of an inward reality, becomes a distinct testimony 
 in proof of the existence of a rational nature, acting in accord- 
 ance with laws distinct from those of organism. As Kussmaul 
 has said in his elaborate dissertation on Disturbances of Speech, 
 distinguishing between physical and psychical or mental, " It 
 is self-evident that psychical (mental) activity must exist 
 wherever sensations are perceived, and judgments are arrived 
 at." 1 Accordingly, the language which expresses discrimina- 
 tion and judgment is a testimony for mind, and, as it affords 
 an index of mental procedure, the study of language may 
 become a medium for the study of mind, as implied in com- 
 parative philology. This truth has been amply illustrated by 
 Professor Max Miiller. 2 
 
 In treating here of the use of language, it is needful in the 
 first instance to have regard to the physical contrivances which 
 make articulation possible, — what has been called "the me- 
 chanism of speech." It is by the management of the larynx, 
 tongue, and lips, that articulation is accomplished. The tongue 
 is a muscular structure capable of varied and delicate move- 
 ments ; and in the larynx there are exquisite muscular arrange- 
 ments regulating the movements of the vocal cords. When a 
 high note is to be sung these cords are brought up to extreme 
 tension, leaving but a slight aperture for the emission of 
 sound. When the singer draws a slight breath the cords are 
 
 1 Ziemssen's Cyclopaedia of the Practice of Medicine, " Diseases of the 
 Nervous System," (Translation,) vol. xiv. p. 692. 
 
 2 Science of Language, 2 vols. 
 
288 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 somewhat relaxed, and the opening proportionally enlarged. 
 When a long breath is drawn the cords are still further re- 
 laxed, and a much wider opening is provided for the reception 
 of air. The organs of articulation are connected with the nerve 
 centre by a variety of tracts, and the nerve fibres concerned are 
 numerous and complicated ; but their distribution to the several 
 ganglia, and portions of the cerebrum, is still matter of very great 
 perplexity. There is, however, a sufficient amount of agreement 
 • to admit of a general statement that the medulla oblongata, 
 the basal ganglia, the cerebellum, and the portion of the frontal 
 lobe of the cerebrum next the fissure of Sylvius are all con- 
 cerned in some degree in the control of the organs of speech. 1 
 Kussmaul states the facts in the following sentences : — " For 
 the purposes of speech there exists an apparatus as vast as it 
 is complicated, consisting of nervous tracts and ganglionic 
 centres, which partly occupy the position of the loftiest work- 
 shops of the conscious intelligence and of the will, and are 
 partly reflex agencies, in which simple and ordered sensory 
 stimuli are converted into motion. Such a thing as a simple 
 ' centre of language,' or ' seat of speech,' does not exist in the 
 brain any more than a ' seat of the soul ' in a simple centre. 
 The central organ of speech is, on the contrary, rather com- 
 posed of a large number of ganglionic apparatuses, widely 
 separated from one another, but connected by numerous tracts, 
 and fulfilling certain intellectual, sensory, and motor functions." 2 
 Kussmaul inclines to localise intellectual functions in the brain. 
 Hence the references to the " workshops " of intelligence and 
 will, and to ganglia fulfilling " intellectual functions," adopted 
 on purely analogical grounds. 
 
 Having regard meanwhile, however, to the " mechanism of 
 speech" alone, and holding in reserve the higher questions 
 concerning the manner in which speech is directed for intel- 
 ligent ends, it is clear that the apparatus which provides for 
 articulate speech must be very complex in structure and 
 arrangement. There is a considerable range of motor acquisi- 
 
 1 See Brooa, Sur le Siige de la Faculty du Langage Articuli ; Kussmaul, 
 Disturbances of Speech, as above ; Bateman Ore Aphasia ; Terrier's Functions 
 of the Brain, and his Localisation of Cerebral Disease. 
 
 2 Cyclopcedia of the Practice qf Medicine, Ziemssen, vol. xiv. p. G14. 
 
x - J USE OF SPEECH. 289 
 
 tion, in connection with which the senses of sight and hearing 
 have much to do before the higher uses of speech are possible. 
 From this point of view, Speech presents a phase of acquisition 
 similar to the first or lower class of acquisitions discussed in 
 the previous chapter. And it is only after this preliminary 
 stage has been passed that the higher uses of speech come into 
 view, providing for a new and greatly higher form of acquisi- 
 tion, and a still more advanced exercise connected with com- 
 munication of thought. 
 
 The motor acquisitions requisite for a free use of speech are 
 many. The nerve action needed for their attainment and co- 
 ordination is necessarily complex, and the apparatus must 
 be brought into regular use, in order to make language an 
 instrument available for intellectual purposes. This subor- 
 dinate and preliminary work for acquiring facility in vocal 
 exercise belongs to the early stages of an intelligent life, and 
 is largely concerned with skilful use of suitable apparatus. 
 How the physical appliances are placed under personal regula- 
 tion is no part of the knowledge requisite for bringing the vocal 
 organs into action. Practice is possible, and it is the essential 
 condition for attainment. In its earliest stages such practice is 
 largely an imitative exercise. Personal effort advances by the aid 
 which is afforded through observation of others. When in this 
 connection we say that imitative tendency is strong in a child, 
 we mean that the child observes what his seniors do, and tries 
 to do in like manner. This is something quite different from 
 the spontaneous crowing or crying of infancy, — something 
 quite apart from the expression of fondness, fear, or pain 
 coming from the higher orders of animals, — and something 
 quite in advance of the imitative tendency shown by a few of 
 the animals. The boundary which separates the two first-named 
 classes of facts from those connected with acquirement of 
 language is broad and very conspicuous. The expressions of 
 the infant and of the higher animals, which, notwithstanding 
 interesting differences, may be classed together, are accounted 
 for by sensory stimuli. Impressions on the sensory nerves 
 act upon motor apparatus. This is the whole explanation. 
 But when the child, passing out of the stage of infancy, 
 begins not only to observe, but so far to concentrate ob- 
 
 T 
 
290 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 servation as to notice what others are doing, and in conse- 
 quence attempts imitation, we need further explanation. It 
 is true that even in this case the child is not separated 
 from sensory stimulus, but this influence is not sufficient. 
 There is work done in a higher sense than when a lamb 
 bleats, or when a rabbit starts away, and a hare crouches in 
 its lair at the sound of a footstep. Here a further contrast 
 between child life and merely animal life meets us. Some 
 animals have imitative tendency as well as man, and it becomes 
 needful to remark that animal imitativeness, and that of a child, 
 as exemplified by use of speech, are quite different. There 
 is, indeed, an imitativeness which belongs to the child just as 
 it belongs to certain animals, but it differs from the imita- 
 tiveness which appears in the acquisition of language. Facts 
 become the more striking and interesting here, on account 
 of the limited number of animals to be considered. We are 
 practically restricted to monkeys, apes, parrots, and mocking- 
 birds. Other animals, which might be included as " perform- 
 ing animals," and often are presented for exhibition as such, 
 are to be excluded, not being spontaneous imitators, but con- 
 strained practisers of actions for which spontaneous aptitude is 
 wanting. "Performing" dogs and pigs and birds and mice 
 are not properly imitators. But monkeys, apes, parrots, and 
 mocking-birds are distinctively imitators, and for the purposes 
 of the present division of this inquiry, they are therefore to 
 be regarded as a distinct class, since no other animals spon- 
 taneously imitate human action as these animals do. A sub- 
 division of this " imitative class " is the next requisite, for it 
 is interesting to remark that there is an essential difference 
 in their imitative tendencies. The monkeys and apes have an 
 anatomical organisation closely analogous to that of man, and 
 they imitate, in their use of the general muscular system, 
 mainly use of the limbs, not use of speech. The parrot and 
 mocking-bird are far removed from resemblance of anatomical 
 structure, and they imitate in vocal effort, not at all in general 
 muscular movements. These contrasts involve a large deduc- 
 tion from the value of imitative acts on the part of the lower 
 animals, as testimony in support of similarity of animal 
 and human life. The apparent approximation in reality carries 
 within it important evidence of wide severance. The refer- 
 
x -l USE OF SPEECH. 
 
 291 
 
 ences previously made (p. 170) to the imitative acts of the 
 anthropoid ape show a strong tendency to imitate all the ordi- 
 nary movements of man when walking from place to place, or 
 sitting at table, but they present no evidence of a tendency to 
 imitate the use of speech. The parrot, on the other hand, imi- 
 tates man in respect of vocal exercise, and in no other respect. 
 The less intelligent animal imitates that action which gives 
 highest evidence of intelligence ; the more intelligent animal (I 
 do not say the most intelligent) imitates that action which is 
 least of all the expression of intelligence. The dog, the most 
 intelligent of animals, does not imitate. Another fact, however, 
 needs to be observed, which does something to compensate, and 
 so far restore the balance between the birds and the monkey 
 tribe. If the parrot imitate the higher exercise, it does so quite 
 clearly under sensory stimulus ; it is not so clear that the 
 imitative activity of the monkey race can be fully explained 
 in this way. The listening parrot presents a case somewhat 
 different from that of the observing monkey. Probably muscular 
 organisation, and the tendency to act in accordance with the 
 adaptations of the muscular system, may account for the cir- 
 cumstance that an animal having the anatomical structure of 
 the monkey, capable of readily assuming a semi- erect posture, 
 and of using the fore-feet to perform the functions of hands, 
 has some muscular inducement (really a sensory stimulus) to 
 imitate man, not manifested by the more intelligent animal, 
 the dog, which has no muscular inducement to imitate human 
 actions, but must experience muscular tendencies inclining in 
 an opposite direction. If this consideration be sufficient, the 
 imitative tendency of the monkey and the ape is explained on 
 the ground of sensory stimuli, as well as that of the parrot. 
 The evidence is more obscure in the case of the larger animals, 
 but there seems no doubt that at least part of the explanation 
 even in their case is found in nerve sensibility. The fact that 
 the monkey is more actively imitative than the ape — the less 
 developed brain more imitative than the more highly developed 
 — must be classified along with the other facts which illustrate 
 greater energy and agility in the smaller animal. And it must 
 certainly stand as one of the facts adverse to the theory that 
 brain development and intellect are necessarily associated. 
 
292 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 With these contrasts before us, the superiority of the imita- 
 tive actions of the child in acquiring command over the vocal 
 organs is very marked. The child is intelligently observant of 
 both movements and sounds, and by power of intelligent com- 
 binations does in the very earliest stages of vocal effort what 
 none of the animals can attempt. Physical combinations are 
 preceded by intelligent combinations, without which speech 
 is impossible. The part which intelligence plays is conclu- 
 sively shown by the illustrations afforded in the case of deaf- 
 mutes, and children even more unfavourably placed. By 
 deduction of important external aids, it becomes more obvious 
 how intelligence struggles against its difficulties, and overcomes 
 them. It is not too much to say that mind has triumphed 
 over physical defect, and worked out an escape from a state of 
 dumbness. It is no doubt true that deafness is generally the 
 primary cause of dumbness — one physical defect hindering the 
 development of the functions of an allied nerve tract, so leaving 
 the vocal organs altogether unexercised and undeveloped. The 
 mute is either completely deaf, or nearly so. In the majority 
 of cases he is born deaf as well as dumb. There is, however, 
 loss of speech by accession of deafness in the earlier years of 
 life. Kussmaul says, '' It seems that the time of puberty 
 is the latest period of life at which deafness can deprive 
 persons of the command of speech, which they have already 
 acquired." 1 The vocal organs having been fully developed 
 and persistently exercised, there is not subsequently a loss 
 of power, even though the advantages of hearing be with- 
 drawn. The labours of those who have undertaken the difficult 
 but noble effort to gain for the dumb the power of speech, 
 by mastery of their special disadvantages, have contributed 
 most valuable evidence as to the relations of mind and 
 brain. It is fully one hundred years since Samuel Heinicke, 
 the Saxon schoolmaster (born 1729, died 1790), began his 
 efforts to teach deaf-mutes to speak. 2 Since his time a large 
 mass of evidence has been gathered, conclusively proving 
 
 1 Cyclop, of Prac. of Medicine, (Translation,) vol. xiv. p. 866. 
 
 2 Heinicke published " On Modes of Thought among the Dumb;" "Im- 
 portant Discoveries in Psychology and Human Language ;" " Samuel Heinicke, 
 Sein Leben und Wirhen." Stoetzner. Leipzig, 1870. 
 
x -] USE OF SPEECH. 293 
 
 that deaf-mutes are capable of being educated, not merely 
 to the use of written, but of spoken language. The essen- 
 tial relationship of intellectual and mechanical effort is strik- 
 ingly illustrated by these educational experiments. The eyes 
 are made to do work for the ears, which in ordinary cases 
 do so much to simplify education. First, by drawings to 
 represent familiar objects, the deaf-mute sees what object is 
 referred to by his teacher. Next, by watching the mouth of 
 the teacher while he slowly and carefully articulates the name 
 of the object, the patient is induced to imitate the movement of 
 the lips, and attempt so much of vocalising effort as is involved 
 in adapting the organs of speech to giving forth the sound. 1 
 Thereafter the range of education is extended by the teacher 
 resorting to such pantomimic action as may aid the understand- 
 ing, while the pupil follows with imitative effort. 2 The 
 dependence of the entire process upon intelligence, noticing 
 objects, comparing representations of them, and observing modes 
 of action adapted to the utterance of their names, is manifest. 
 Such training first demands intelligence as its prerequisite, and 
 next develops it in a higher degree, by affording to it a wider 
 range of exercise. The attempt to vocalise, being more compli- 
 cated than the attempt to produce written characters, contributes 
 more powerfully to the training of mind. A boy in Leipzig, 
 seven years of age, who was a deaf-mute, had within a period 
 of six months learned to write, but he had no understanding of 
 the meaning of the words, thus illustrating the lower form 
 of imitative tendency. After that period he began to attempt 
 vocalising, thus connecting pictorial representations and written 
 characters with efforts at articulation, — a higher exercise of 
 imitative power, in which greater demand was made upon in- 
 telligence, and greater development of it was the natural result. 
 Thus have the deaf-mutes aided us in the important experi- 
 ment of separating the distinct exercises involved, and showing 
 more conspicuously how truly intelligence is the director of 
 nerve energy. An intelligent power which is capable of dis- 
 criminating and comparing pictorial representations with the 
 
 1 See note on "lip reading," Carpenter's Mental Physiology, p. 204. 
 
 2 Imagine this experiment tried with a monkey, the most imitative in 
 action, or with a dog, the most intelligent of animals ! 
 
294 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 objects they represent, distinguishing different forms of labial 
 and lingual action employed by another person, and directing 
 the organs of speech in the attempt to produce similar move- 
 ment with vocalisation, places its possessor within the circle 
 of the educable, even though there be organic obstacles to be 
 overcome by him. In such cases, mind conquers the physical 
 inaptitude, and at length makes the formerly inactive organ 
 of speech a pliant servant of intelligence. 
 
 In the present argument, it is important to distinguish be- 
 tween nerve sensibility, intellectual action, and motor activity. 
 Education of the deaf-mute does not proceed without some 
 use of nerve sensibility. If the ear does little, the eye does 
 so much more. The picture, movements of the lips and 
 tongue by the teacher, and accompanying gesticulations, are 
 all essential. The sensibility of the optic nerve is largely 
 employed. But such sensibility is insufficient to account for 
 the facts. The retina, the optic nerve, and the optic centre in 
 the brain all fulfil a distinct part in the process. Destroy the 
 optic apparatus, and a second avenue to the intelligence is 
 closed, as the auditory was in the first instance. But it is only 
 an avenue, a nerve apparatus for conducting a class of sensory 
 impressions. If such impressions are not transmitted, the in- 
 telligence is still the same, even though it is shut off from 
 another inlet of information, and deprived of important occa- 
 sions for its exercise. But while we speak of sensory impres- 
 sion in the brain, the deliberate comparison of one impression 
 made by the pictorial drawing, with another made by the 
 object itself, is an exercise for which the sensory apparatus 
 is inadequate (see p. 220), and motor energy is insufficient, 
 and for which a power higher than both is required. It is this 
 higher power, and it alone, which provides for intelligent appre- 
 ciation of the purpose of the instructor in directing attention 
 simultaneously to the object and its pictorial representation. 
 If the simple perception of the two things with dependent 
 motor activity were the utmost possibilities in the case, the 
 educational process could not advance. The look of recog- 
 nition between pupil and teacher is the conscious agreement 
 of two minds for the accomplishment of a contemplated end. 
 
 In accordance with the facts in this particular case (and 
 
x.] USE OF SPEECH. 
 
 295 
 
 with the general argument as to sensation, p. 220), there is a 
 self-directed exercise of intelligence on the part of the deaf- 
 mute, which is the most potent factor in the process. The 
 most valuable efforts of the instructor, operating on the best 
 developed brain, would have comparatively little influence, 
 were it not for the voluntary and intelligent effort of the pupil. 
 That this effort of the deaf-mute is in part imitative is clear, 
 but the imitative process would be reduced to grotesque panto- 
 mime if evidence were wanting of the direction of the inter- 
 preting mind. In a very important sense, which holds true in 
 all education, the deaf-mute is self-educated. His condition 
 would have involved a very restricted exercise of intellectual 
 power, if the skill and benevolence of the teacher had not 
 brought to him important aid for mastering the restraint placed 
 on the vocal organs ; but that teaching would have been dis- 
 appointingly slow and limited in result had there not been 
 the self-directed and intelligent action of one eager to learn, 
 and to escape the thraldom of enforced silence. 
 
 In confirmation of this view, there are recorded cases which 
 enable us to form some estimate of the intelligence of the 
 deaf-mute at the earliest stages of life. The following case, 
 presented by Kussmaul, may suffice for illustration : — " It has 
 been pointed out that from birth onwards, deaf-mutes have 
 learned to recognise properly both things and relations. A 
 case related by Kruse (Ueber die Taubstumrnen, Schleswig, 
 1853), bearing upon this point, is particularly instructive. 'A 
 deaf and dumb boy was in 1805 found by the police, straying 
 about Prague. Not being able to make anything out of him, 
 they placed him in an institution for deaf-mutes, where he 
 received instruction. When sufficiently educated to give 
 accurate answers to questions put to him, he gave a description 
 of as much of his former life as remained in his memory. His 
 father, he said, owned a mill ; he described the furniture of the 
 house, and also its surroundings minutely; he gave a full 
 account of his life while at home ; told that his mother and 
 sister had died, and that his father had married again; and 
 that his step-mother ill-treated him until he had run away. 
 But he neither knew his own name, nor that of the mill ; he 
 knew, however, that it lay to the east of Prague. Inquiries 
 
296 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 were made, and the statements of the boy were found to be 
 correct. The police found his home, gave him his proper name, 
 and secured to him the succession to his father's property.' 
 Prom this we see that a deaf boy, who had not learned phonetic 
 speech, had nevertheless stored up a multitude of accurate 
 recollections, and "was able, by the exercise of judgment, to 
 arrive, through them, at correct conceptions of very intricate 
 relations." 1 It is quite possible, as Kussmaul suggests, that 
 the boy, after having been instructed, had recalled all the 
 scenes of his youth, and brought the whole into intelligible 
 unity before his mind. Such intellectual exercise on his part 
 is not only probable, but even certain. Yet this does not in 
 the least detract from the value of the evidence that he had, at 
 the earlier stage, "by the exercise of judgment," arrived at 
 " correct conceptions of very intricate relations." The possi- 
 bility of afterwards reconstructing into a harmonious whole 
 the scenes and relations of early life, presupposes that he had 
 previously accurately distinguished and remembered the rela- 
 tions in which he was placed. 
 
 Still lower than this case it is possible for us to go in the 
 records of loss of special sense with loss of speech, and prose- 
 cution of educational effort in face of great difficulties. The 
 celebrated case of Laura Bridgman must be regarded as the 
 crucial test of education with least possible aid of the senses. 2 
 Though it does not illustrate use of speech, I refer to it briefly 
 as of value in the present connection. In her second year, 
 Laura Bridgman, while suffering under scarlet fever, became 
 blind and deaf, and was also in great measure deprived of smell 
 and taste. Her exercise of intelligence in acquisition of know- 
 ledge of the outer world depended exclusively on the sense of 
 touch. When Dr. Howe, her instructor, found her, she was 
 seven years of age, having been born in 1829, and was a "lively 
 girl," living in a village in the mountains. He made arrange- 
 
 1 Cyclopcedia of the Practice of Medicine, Ziemssen, vol. xiv. p. 598. 
 
 2 The case is reported in the Forty-Third Annual Report of the Perkins 
 Institution and Massachusetts Asylum for the Blind. It is referred to by 
 Kussmaul, is given at considerable length by Dr. Ireland in his work on 
 Idiocy and Imbecility, p. 225 ; at still greater leDgth in Kitto's Lost Senses ; 
 it is also described in George Combe's Notes on the United States ; and in 
 Dickens's American Notes. 
 
x.] USE OF SPEECH. 297 
 
 ments for taking her to Boston, received her into his own 
 house, and began the arduous task of instruction. She, for her 
 part, laboured most diligently, and, after having continued her 
 studies for fully twenty years, was able to converse " readily 
 and rapidly " by signs, to read books in raised character, to find 
 any chapter and verse in Scripture, to keep a diary, and to 
 write letters to her friends. The early stages of her education 
 involved the following methods. Dr. Howe took such articles 
 as a pen, a pin, a key, and spoon, — restricting names to mono- 
 syllables ; the articles were laid on the table that she might 
 feel them ; she was then made to feel the doctor's finger as he 
 formed the letters for pen according to the manual alphabet ; 
 and this was repeated until she grew familiar with the signs, 
 and associated them with the things. Next, the printed cha- 
 racters were cut out and pasted on the articles, and thereafter 
 single characters were cut, and she was set to arrange them in 
 proper order, afterwards placing the name on the" appropriate 
 article, in order to test accuracy. She became conscious that 
 she was making out the names " pen " and " pin." The smile 
 of satisfaction passed over her face, and Dr. Howe could 
 say, " I now felt that the first step had been taken successfully, 
 and that this was the only really difficult one." The lessons 
 were extended to embrace a larger number of objects; the 
 numerals were learned, with marks of punctuation and interro- 
 gation. She became so deeply interested that "she worked 
 eagerly and incessantly ;" at times she was " too radiant with 
 delight to be able to conceal her emotions." She carried on 
 the exercise when alone, repeating over and over again the 
 same word. While so engaged, she was seen to detect her 
 blunders ; turning her head a little to the side with a smile, 
 she gave her right hand a slap with the left hand, as her 
 teacher was in the habit of doing. As a stage in advance, 
 types were made for her which could be fitted into openings in 
 a board, leaving only the characters above the surface. "With 
 these she soon became familiar, and she began to arrange them 
 rapidly. Thereafter she became equally well acquainted with 
 the same forms raised on the surface of paper, and she was able 
 to read printing as prepared for the blind. 
 
 At the earlier stages of this educational process, the child 
 
298 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 was only imitating, without recognising any intelligent end to 
 be served; but from the moment she began to understand 
 what was being done, she began the use of written language. 
 Eeferring to the contrast between these two stages, Dr. Howe 
 writes thus : — " The poor child had sat in mute amazement, and 
 patiently imitated everything her teacher did. But now the 
 truth began to nosh upon her; her intellect began to work; 
 she perceived that there was a way by which she could herself 
 make up a sign of anything that was in her own mind ; it was 
 no longer a dog, or a parrot ; it was an immortal spirit eagerly 
 seizing upon a new link of union with other spirits. I could 
 almost fix upon the moment when this truth dawned upon her 
 mind, and spread its light to her countenance." It is upon 
 this intensely interesting period in the history of the case that 
 Mr. Dickens has dwelt with manifest joy, as one not to be for- 
 gotten by her instructor. Very fitly does Dr. Howe express 
 the ground of confidence he had in persevering with a task so 
 puzzling, and so full of suggestions of hopelessness. " Without 
 the belief, and indeed the certainty, that the mind of Laura 
 was endowed with some attributes which the most highly 
 gifted brutes utterly lack, I should not have attempted to 
 bring her out of her mental darkness into light, any more 
 than I should have attempted to bring out the mind of my 
 dog Bruno, which seemed to know as much as Laura then did, 
 and which I loved and prized almost as much as if he had 
 been human." 
 
 This case, along with the preceding illustrations of " lip 
 langiiage," strikingly illustrates the distinction between the 
 merely imitative exercise and the discriminating power which 
 is able to interpret and employ for its own ends arbitrary signs 
 gathered together in a recognised order. As to acquisition of 
 speech, it is obvious that analysis of the process gives us the 
 following distinct facts : — (1.) observation by sight of lip move- 
 ment; (2.) observation by hearing of vocal effects, the latter 
 being the more important and helpful for the end contem- 
 plated, but both possible to animals ; (3.) use of motor energy 
 for vocalising, stimulated by a sensory influence, and possible 
 to some animals; (4.) intelligent appreciation of vocal signs, 
 and accompanying gesticulations, which may be seen in the 
 
x.] USE OF SPEECH. 299 
 
 dog ; (5.) intelligent appreciation of the distinct characters, and 
 their exact relations when combined to represent vocables, an 
 exercise performed by no animal ; (6.) an intelligent voluntary 
 direction of motor energy towards the imitation of vocalisation 
 for an intelligent end ; (7.) voluntary exercise in vocalisation 
 with the view of attaining facility in utterance ; (8.) voluntary 
 use of speech as an aid to discrimination of things, and to 
 direction of the thoughts concerning things. The last intro- 
 duces to the free use of speech as an intellectual exercise, and 
 a powerful auxiliary for the development of intelligence. Prom 
 these considerations it appears that use of speech implies acqui- 
 sition by an imitative process possible to animals, and acqui- 
 sition by means of intelligent discrimination not possible to 
 animals. It further appears — and this is the essential point 
 — that intelligent action is not an after result flowing from the 
 lower imitative exercise, and developed out of it, hut a prere- 
 quisite, without which the educational process could not proceed. 
 The lack of this makes the education of the dog, or horse, or 
 ape, by use of language impossible. The possession of it makes 
 the education of the child possible, even when deprived of the 
 aids of sight, hearing, and smell, the existing intellectual power 
 being sufficient to overmaster the vast perplexities which such 
 privation involves. Brain power is in such a case put at the 
 greatest disadvantage for the use of motor energy in the manage- 
 ment of the vocal organs. But these difficulties are overcome 
 by a higher power operating in a manner superior to normal 
 brain action. Motor energy is first directed by intelligence, 
 and afterwards it is utilised to aid intellectual exercise, and 
 also memory in storing treasures of knowledge. Thus mind is 
 not superinduced on sensori-motor activity, as a later result, 
 but is educed or led forth to aid the senses and utilise them, 
 according to the true nature of education. 
 
 In confirmation of these conclusions, a few sentences from 
 Kussmaul may be added, more especially as this author 
 is disposed to assign a wide range of influence to brain 
 action. Speaking of the German method of instructing deaf- 
 mutes by " lip-language," or attempts at vocalisation, he makes 
 the following statements : — " The instruction is of two kinds, 
 intellectual and mechanical. 1. The intellectual aims at the 
 
3oo THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 production and combination of ideas drawn from sensory im- 
 pressions. ... 2. The mechanical instruction aims at the pro- 
 duction of articulated sounds and words. . . . The intellectual 
 and mechanical instructions are carried on up to a certain time 
 independently of one another, but the intelligence and speech 
 nevertheless react upon one another, and become intimately 
 interwoven." 1 In fact, action and interaction are so essential 
 here, that the mechanical cannot advance without the direct- 
 ing work of intellect ; that is, action which is not originated 
 by sensory or motor stimulus. The first step with Laura 
 Bridgman, " the only really difficult one," as Dr. Howe has 
 said, was the interpreting of certain signs ; it was not sensory 
 impulse, leading to co-ordination and co-action of nerve centres 
 followed by combinations of motor activity. On these grounds 
 the words of Professor Max Miiller, though startling in form, 
 and liable to be misinterpreted, are not too strong when 
 taken in the sense intended — " without speech no reason ; 
 without reason no speech." 2 The two clauses obviously cannot 
 have the same force, for of the two powers one must be superior 
 to the other. It is impossible that speech should be the cause 
 of reason, and at the same time reason be the cause of speech. 
 Cause and effect cannot change places. But if it be meant that 
 reason cannot be developed without use of language, and neither 
 can it be acquired without use of reason, this is the truth which 
 the preceding investigations seem to have established. If there 
 were no discriminating power directing the use of special senses, 
 speech could not be acquired, even though the mechanical ap- 
 pliances for vocalisation were in existence, and nerve force 
 abundant. Intelligence is the essential requisite. But when 
 the mechanical contrivances have been brought into use under 
 the guidance of intelligence, and for rational ends, facility of 
 speech is obtained. Then acquired language, with power of 
 free vocal use of it, becomes an agency for higher action of in- 
 telligence, and higher development of all that belongs to an 
 intelligent nature. This holds true in a still more important 
 sense, when speech becomes the vehicle of communication be- 
 tween mind and mind. Man, by use of language, formulating 
 his own thoughts, gives to them greater clearness and precision, 
 1 Cyclopadia, vol. xiv. p. 872. 2 Science of Language, vol. ii. p. 269. 
 
x ] USE OF SPEECH. 30 1 
 
 and makes them at once helpful to others and contributory to 
 personal advance. 
 
 Here the argument touches upon the disputed question in 
 philosophy, Is language necessary to thought ? There is no 
 need for here entering upon the history of this dispute. The 
 full answer to the question is, that a measure of thought is 
 possible without language; but for free and accurate use of 
 thought, it is needful to formulate our thoughts, and for this 
 language is necessary. The legitimate conclusion obviously 
 is, that language of some kind is needful for full use of intel- 
 ligence. In this connection it is interesting to note that, in 
 the case of Laura Bridgman, it was observed that when think- 
 ing alone she spoke on her fingers, and that the same exercise 
 went on during her sleep when she was dreaming. 
 
 If now we pass from acquisition of speech, to the ordi- 
 nary use of it in communicating thought to others, either con- 
 versationally or in public discourse, very strong confirmatory 
 evidence is found for the distinctness and superiority of 
 mental action. We see a discriminating nature using an in- 
 strument to aid it in its own proper work. Language first 
 becomes an aid to the distinguishing of objects ; next to the 
 recollection of what has been recognised ; by another step it 
 becomes helpful in comparing the observations and thoughts of 
 others with our own ; next, it is an instrument for discovery of 
 truth in a deeper and more abstract sense; and at length it 
 becomes the vehicle of conveying to others the most matured 
 results of reflection on the subjects which profoundly interest 
 an intelligent being. In these familiar facts there is a clear 
 and broad distinction between the mechanical and the intelli- 
 gent. Admitting sensory stimulus and motor activity as 
 quite essential for explanation of the use of our vocal organs, 
 they are quite insufficient to account for the simplest and 
 most ordinary use of speech. It is not at all difficult to find 
 vocalisation which may be adequately accounted for by sensory 
 stimuli. A sudden start, or unexpected infliction of pain, will 
 immediately occasion exclamation (p. 240). The motor centres 
 concerned with the management of the vocal organs have been 
 proved to be co-ordinated with the sensory centres of sight and 
 hearing. Any sudden and powerful action of either of these 
 
3Q2 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 senses may therefore be sufficient to call forth expression. But 
 to attempt to explain the ordinary use of language on the 
 hypothesis that such brain action accounts for all, is simply 
 impossible. The most ordinary conversation will supply ample 
 material to demonstrate the unscientific nature of the attempted 
 explanation. Observe a conversation in which facts are not 
 merely stated, but diversity of understanding concerning the 
 facts is expressed, making it an object for those interested to 
 determine exactly how the matter stands, and it is obvious, 
 after allowance has been made for sensory impression, and 
 voluntary vocal action, that the most important fact, which is 
 the key to the whole, is unexplained. Simple observation of 
 the countenance of those taking part in the conversation makes 
 us constantly sensible of this, and the current of conversation 
 is largely decided by such observation. "We see that our words 
 are being heard and interpreted by others ; but we also see that 
 doubt has been awakened in the mind of some. This could 
 not have been but for the hearing of the words spoken, but 
 neither could it have been without recollection of other statements 
 different in nature, and comparison of the two. The explana- 
 tion lies beyond sensori-motor apparatus. This becomes clear 
 as we listen to the counter-statements which follow. We 
 almost see the doubt finding utterance for itself, and revealing 
 its character as distinct from the sensory impressions and 
 motor actions involved. The eye even more than the lips 
 reveals that there is a discriminating and balancing process 
 going on with the speaker while he utters his thoughts. All 
 are familiar with the difference between the eye of a listener 
 and the eye of the same man when expressing his own thoughts, 
 and carefully guarding his words that they may quite accu- 
 rately state his view of a case. We see the eye moving slowly 
 hither and thither, looking all round the room, with a remote 
 look which tells that the man is seeing nothing, or, we may 
 say, seeing things without seeing them, because caring nothing 
 for the images reflected on the retina. Such action of the eye 
 is never seen in an animal. The speaker is deliberately stating 
 his thoughts, arranging them in suitable order, carefully select- 
 ing his words, rectifying them at times by recalling a word and 
 substituting another. Intelligence is revealing itself by the 
 
*•] USE OF SPEECH. 
 
 3°3 
 
 agency of speech. All the sensory and motor apparatus at 
 command are needed to accomplish the result ; but these are 
 equally necessary for simple narrative, and for the most 
 guarded expression of opinion. In this way deliberate utter- 
 ance bears witness to a power higher than motor force. 
 
 Further evidence is presented by continuity of speech 
 in public discourse when one is guiding the intelligence of 
 many. Take the case of the public speaker who has pondered 
 a subject, distinguished its subdivisions and their relations, 
 resolving upon the general combinations he will adopt in order 
 to convince others, but leaving for selection at the moment the 
 words in which he shall express his thought. Having certain 
 leading conceptions before his mind, he has grasped them in 
 their nature and relations ; but he has not formulated the dis- 
 course which is to be uttered when he is before his audience. 
 He has apparatus, and stores of vocables, and a definite gather- 
 ing of thoughts to be expressed. We listen at first to slow and 
 guarded utterance ; we see the eye kindle, and hear the words 
 come faster and more emphatically; we see the evidence 
 of rising and falling passion; we hear a deliberate course of 
 argument, in which we see and hear the speaker carefully 
 advance from one position to another ; when this is over the 
 aspect of things is changed, and we hear a strong appeal in 
 favour of the conclusion commended to the audience. To say 
 that all this is accomplished not with the aid merely of vocal 
 apparatus, but by vocal apparatus alone, is simply to abandon 
 the attempt to find a scientific explanation. The discriminating 
 power at work cannot be overlooked, nor the careful adaptation 
 to rational ends. "Without long experience in speaking, and 
 acquired facilities in utterance, and stores of vocables in the 
 memory, the thing cannot be done ; but that which we con- 
 template is a self-determined order of thought making itself 
 felt beyond the circle of the personal life from which it comes, 
 and bearing strong marks of the personality to which the 
 utterance is due. There is a common impression made on the 
 audience in so far as the sensory impressions are concerned, 
 but there is a distinct result in the experience of each auditor, 
 according as assent has been given, or doubt entertained, or 
 dissent taken, while listening. 
 
304 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 Striking confirmation of the difference between intellectual 
 action and the sensori-niotor activity involved in the use of 
 vocal organs, is obtained by reference to facts connected with 
 loss of speech, known as Aphasia. Dr. Bateman clearly draws 
 this distinction : — " Speech is a complex faculty, consisting of 
 two distinct elements, one physical, somatic, and material — a 
 movement; the other psychical — the interior speech — the 
 \6yos ; and we must take care not to confound this inward with 
 the outward speech or articulation, which is only a form of ex- 
 pression." 1 This is the distinction which has been made on 
 clear evidence in the earlier part of this chapter, and which it 
 is necessary to apply in order to explain the pathological facts 
 connected with loss of speech. Accordingly, in explaining the 
 use of the term Aphasia by such authors as Trousseau, Broca, 
 Voisin, and others, he says it is used " to designate that condi- 
 tion in which the intelligence is unaffected, or, at all events, 
 but slightly impaired ; where thoughts are conceived by the 
 patient, but he cannot express himself, either because he has 
 lost the memory of words, or because he has lost the memory 
 of the mechanical process necessary for the pronunciation of 
 these words ; or because the rupture of the means of commu- 
 nication between the grey matter of the brain and the organs 
 whose co-operation is necessary to produce speech, does not 
 allow the will to act upon them in a normal manner — the ideas 
 are formed, but the means of communication with the external 
 world do not exist." 2 
 
 M. Broca of Paris has worked long and carefully at the con- 
 dition of brain in cases coming under such a description as that 
 just given, and he adopted the view that there is in general 
 some disease on the rear portion of the frontal lobe, bordering 
 the Sylvian fissure (see p. 18, innermost No. 1), and that the 
 lesion is commonly on the left hemisphere, as previously 
 maintained by Dr. Dax, — a fact which has been ascertained 
 to be connected in some measure with the use of the right 
 hand. 
 
 In other cases the lesion has been found on the right hemi- 
 
 1 On Aphasia, or Loss of Speech, and the Localisation of the Faculty of 
 Articulate Language, by Frederic Bateman, M.D., p. 95. 
 
 2 lb. p. 94. 
 
X -J ■ USE OF SPEECH. 305 
 
 sphere rather than the left. 1 Professor Sanders, Edinburgh 
 University, has found restraint on speech connected with lesion 
 of the Island of Eeil. 2 There is a large amount of evidence in 
 support of the theory that the centre of speech is to the rear 
 of the frontal lobe, but this cannot be regarded as a settled 
 point. 
 
 Many of the recorded cases of loss of speech are full of interest 
 to the psychologist. They illustrate considerable diversities in 
 the degree in which speech is lost, presenting some analogy to 
 the various difficulties in acquiring language, and enabling us 
 the more fully to discriminate between intellectual activity and 
 motor restraint. Those diversities include such facts as the 
 following : complete loss of language under the influence of 
 fever, followed by complete recovery of language after the fever 
 had passed away ; loss of speech in the same circumstances, with 
 necessity for acquiring it anew as in childhood ; permanent loss 
 of speech on account of established disease of the brain, which 
 is often a precursor of impending paralysis. Such a variety 
 of cases greatly aids the work of discrimination between mental 
 and physical activity. The observer, travelling along a path- 
 way at the opposite extreme of human experience, at length 
 discovers a condition as restricted as that of Laura Bridgman 
 in her youth, when a barrier of physical difficulties blocked 
 the avenues to her mind. Some illustration of the three classes 
 of examples will suffice for the requirements of the present 
 argument. 
 
 The first and simplest class of cases includes all those in 
 which there is temporary loss of speech and language during a 
 diseased condition, followed by full return of power along with 
 restoration of health. One of the most striking examples of 
 this occurred in the life of Mezzofanti (Giuseppe Gaspardo), 3 
 who was born at Bologna in 1774, was made Professor of Arabic 
 in the University, 1797, went to Bome, 1832, where he was 
 appointed Librarian to the Vatican, and was in. 183 8 made a 
 
 1 Impairment of Language, the result of Cerebral Disease, by Dr. W. A. 
 F. Browne of Crichton Royal Institution, West Siding Reports, vol. ii. p. 278. 
 Dr. Hughlings Jackson, London Hospital Reports, 1864. 
 
 2 Lancet, June 1866 ; Edinburgh Medical Journal, August 1866. 
 
 3 Life of Cardinal Mezzofanti, by C. W. Russell, D.D., Maynooth. 
 
 V 
 
306 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 Cardinal, and died in 1849. 1 He was capable of speaking 
 fluently in thirty languages, " and was acquainted in various 
 degrees with seventy-two." When installed as a Cardinal he 
 received congratulations from fifty-three members of the Propa- 
 ganda. They offered " their greetings in their various tongues," 
 and to each Mezzofanti replied in the tongue in which the con- 
 gratulatory words had been spoken. " A brief attack of fever 
 completely blotted out the seventy-two languages of which he 
 was master, while the cessation of the paroxysm witnessed 
 their restoration." 2 The effect was "to suspend his memory 
 altogether." 3 A disordered physical condition affecting the 
 brain deprived the sufferer of his vast stores of knowledge, as 
 well as his facility of speech. So far, however, were these 
 stores from being really lost, that removal of the physical 
 disturbance was enough to show that they were still at com- 
 mand. The case does not illustrate a "blotting out" of 
 impressions which needed to be imprinted anew on the sub- 
 stance of the brain, but a temporary obstruction to the use of 
 that which was really in possession. 
 
 One of the most striking examples belonging to this class is 
 that reported by Dr. S. Jackson, of Pennsylvania, as occurring in 
 the experience of a clergyman, 48 years of age, caused by check 
 of perspiration under exposure to the night air. 4 In this case 
 the evidence is complete in proof of perfectly clear exercise of 
 intelligence, with entire loss of speech. Dr. Jackson " found 
 the patient in full possession of his senses, but incapable of 
 uttering a word. The tongue was not paralysed, but could be 
 moved in every direction ; all questions were perfectly compre- 
 hended and answered by signs, and it could be plainly seen 
 by the smile on the countenance, after many ineffectual 
 attempts to express his ideas, that he was himself surprised, 
 and somewhat amused, at his peculiar situation. The face 
 was flushed, the pulse full and somewhat slow, and to the 
 
 1 See Philol. Soc. Proceedings, January 1852. Quarterly Review, vol. ci. p. 23. 
 
 2 Impairment of Langvage. By Dr. Browne. Wat Riding Reports, vol. ii. 
 p. 291. 
 
 3 Life of Mezzofanti, by Dr. Marshall, p. 309. 
 
 4 Reported in American Journal of Medical Sciences, February 1829, 
 p. 272. Quoted by Dr. Batcman, On Aphasia, p. 56. 
 
x d USE OF SPEECH. 307 
 
 inquiries if he suffered pain in the head, he pointed to his 
 forehead as its seat. When furnished with pen and paper, he 
 attempted to convey his meaning, but he could not recall 
 words, and only wrote an unintelligible phrase, ' didoes doe 
 the doe.' Forty ounces of blood were drawn from the arm, 
 and before the operation was completed speech was restored, 
 though a difficulty continued as to the names of things, which 
 could not be recalled. The loss of speech appearing to recur 
 in fifteen minutes, ten ounces more blood were abstracted, and 
 sinapisms (mustard poultices) applied to the arms and thighs 
 alternately. These means were speedily effectual, and no 
 further return of the affection took place." 1 Dr. Jackson's 
 analysis of the case is the following : — " Firstly, sudden sup- 
 pression of the cutaneous transpiration, succeeded by cerebral 
 irritation and determination of blood to the brain. Secondly, 
 frontal pain immediately over the eye. Thirdly, perfect in- 
 tegrity of the sensations and voluntary movements. Fourthly, 
 the general operations of the intellect undisturbed ; ideas 
 formed, combined, and compared; those of events, of time, 
 recalled without difficulty. Fifthly, loss of language or of the 
 faculty of conveying ideas by words, though not by signs — 
 this defect not being confined to spoken language, but also 
 extending to written language." 
 
 From this class of cases it appears not only that intelligence 
 depends for its use of language upon a healthy condition of 
 the motor centres through which it habitually regulates the 
 organs of speech ; but that intelligence may be undisturbed in 
 its own operations, while a complete restraint is placed on the 
 government of the vocal organs. 
 
 A second class of cases, including a considerable number of 
 those reported, is that in which a more serious injury is in- 
 flicted, and language has to a considerable extent to be reac- 
 quired. Professor Graves of Dublin reported 2 the case of a 
 Wicklow farmer, aged fifty, under paralysis of one side, who 
 " was affected with an incapacity to employ nouns and proper 
 names, he being able in other respects to express himself well." 
 He however " perfectly recollected the initial letter of every 
 
 1 Bateman On Apltasia, p. 57. 
 
 2 Dublin Quarterly Journal, February 1851. 
 
3o8 THE RELA TIONS OF MIND AND BRAIN. [chap. 
 
 substantive or proper name for which he had occasion in his 
 conversation. ... He consequently made for himself a little 
 pocket dictionary of the words in most frequent use, . . . and 
 during a conversation he would look in his dictionary till he 
 found the word he wanted." 1 Another case is recorded by Dr. 
 Hun -of Albany, United States, the sufferer being a blacksmith, 
 thirty-five years of age, who, after a long walk under a burning 
 sun, was seized with symptoms of congestion of the brain, and 
 for several days lay in a state of stupor. When he recovered 
 from this state he understood what was said to him, but had 
 great difficulty in expressing his desires in words, on account 
 of which he resorted to signs to convey his meaning. If the 
 name of a thing he wished was uttered in his hearing, he would 
 say, " Yes, that is it," but he still continued unable to name it. 
 " After fruitless attempts to repeat a word, Dr. Hun wrote it 
 for him, aud then he would begin to spell it letter by letter, 
 and after a few trials was able to pronounce it. If the writing 
 were now taken from him he could no longer pronounce it, 
 but after long study of the written word and frequent repeti- 
 tion, he would learn it so as to retain it and afterwards use it. 
 He kept a slate, on which the words he required most were 
 written, and to this he referred when he wished to express 
 himself. He gradually learned these words and extended his 
 vocabulary, so that after a time he was able to dispense with 
 his slate." 2 The striking feature in this case is the slow pro- 
 gress in reacquiring the words, in connection with which it is 
 important to remark that there was no paralysis of the tongue. 
 A complete contrast as to acquisition is found in a case re- 
 ported by Dr. W. A. F. Browne, of the Crichton Institution, 
 Dumfries, the sufferer being a person much more highly edu- 
 cated than either of the two just mentioned. " A young 
 married lady, on recovering from dementia and stupor suc- 
 ceeding hysterical paralysis, was found to have retained no 
 knowledge whatever of any of the events, or acquisitions, in- 
 cluding languages, writing, music, etc., of her previous life, 
 even of her marriage. She learned the alphabet and the lan- 
 guage so long used by her, writing, knitting, etc., as a child, 
 but with much greater rapidity and facility than a child could 
 1 Dublin Quarterly Journal, p. 53. a lb, \>. 58. 
 
x -1 USE OF SPEECH. 309 
 
 have done, and never regained the same command of the ver- 
 nacular as she formerly displayed." 1 
 
 In such cases as these it seems certain that the action of 
 disease produced some disturbance and change of brain struc- 
 ture. The change cannot involve a complete wasting or de- 
 struction of the centres concerned with speech, for some 
 portion of the facility is retained, and there is undisturbed 
 action of intelligence. The Wicklow farmer, while restrained 
 in his use of names, was "able in other respects to express 
 himself well." The Albany blacksmith " understood what was 
 said to him." The young married lady had retained none of 
 her knowledge, but she acquired " with much greater rapidity 
 and facility than a child could have done," a fact which may 
 partly be credited to a remnant of brain acquisition, but chiefly 
 to her previous intellectual training, for the motor acquisitions 
 were less available than the intellectual power brought to bear 
 upon what was for her, in her recovery, completely new intel- 
 lectual work. 
 
 The third class of cases includes those in which there is 
 decided and incurable brain wasting, the loss of speech being 
 only one of several symptoms, and commonly a symptom 
 premonitory of more extensive and serious disorder. There is 
 complete loss of will power over the motor centres which 
 regulate the organs of speech, and yet there are conclusive and 
 strong evidences of accurate intellectual action. Broca's case 
 of Lelong, a labourer, aged eighty-four, in the hospital at Bicetre, 
 where he had been for eight years suffering under senile de- 
 bility, is a very striking one. As the result of a fall down a 
 staircase, he became unconscious, and was treated for apoplexy. 
 In a few days he was convalescent ; but he had lost speech, 
 being able to articulate only five words, and these with diffi- 
 culty. The words were " Lelo " for his own name, and " oui, 
 non, tois (for trois), and toujours." " His intelligence had re- 
 ceived no appreciable shock ; he understood all that was said 
 to him, and his brief vocabulary, accompanied by an expressive 
 mimic, enabled him to be understood by those who lived 
 habitually with him." 2 Having so few words at command, he 
 
 1 West Biding Reports, vol. ii. p. 289. 
 
 2 Bateman's Aphasia, p. 9. 
 
310 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 used them often inappropriately. " Oui " and u non " sufficed 
 for expression of assent and dissent; but every number was 
 named three ; and every thing besides was placed under 
 "toujours;" whatever the object, its name was "always." 
 Nevertheless, the patient clearly recognised the error involved 
 in his utterance, and did his utmost to correct it. If asked 
 how long he had been at Bicetre, he said " tois," but gave the 
 correct number of years by holding up eight fingers. At ten 
 o'clock he was asked what o'clock it was, and, as usual, he said 
 " tois," but he held up his ten fingers. 
 
 A very important case is recorded by Dr. Bateman, as having 
 come under his own observation, that of a waterman named 
 Sainty, fifty-one years of age, and who " seemed possessed of 
 more intelligence than most men of his class." At the close of 
 1864, after unloading his vessel, he suddenly experienced loss 
 of the power of speech, which continued for about three days, 
 after which it began gradually to return. About two months 
 later, February 1865, he felt numbness of one of the fingers of 
 the right hand, and a month later fell down in a fit. He then 
 came under Dr. Bateman's care in the Norfolk and Norwich 
 Hospital, at which time there was " no want of sequence in his 
 thoughts, but he was unable to give expression to them." He 
 was discharged from hospital in June of the same year, resumed 
 work, and continued at work till January 1866, when he fell 
 down in a state of unconsciousness ; a month later, the same 
 thing occurred; and a repetition of the fit came upon him 
 every few weeks, but still there was no paralysis. He was re- 
 admitted to the hospital in January 1867, at which time he 
 understood all that was said, could fetch anything when asked 
 to do so, but could not name things, though he could recognise 
 the name as correct when pronounced by another. Thus he 
 was shown a poker, and asked what it was, to which he replied 
 that he knew, but could not name the word. He was asked, 
 Is it a walking-stick ? No. A broom ? No. A poker ? To 
 this he at once said Yes, with a smile of recognition. About 
 three months after re-admission he had an epileptic fit, without 
 paralysis ; in less than a month thereafter another fit, followed 
 by paralysis of the lower limbs, from which, however, there 
 was recovery within a day. A week later the fit returned, 
 
x.] ■ USE OF SPEECH. 311 
 
 with paralysis of the right side. In three days he had so far 
 recovered the use of his limb as to be able to walk a few steps 
 alone, but could not speak, though he made signs. He put his 
 hand to his forehead as if in pain, and became so restless that 
 he needed an attendant to keep him in bed. After this the 
 case developed into insanity, under which he still recognised 
 those known to him, and gesticulated violently, endeavouring 
 " by the language of signs to supply the loss of articulate lan- 
 guage." 1 In this case the evidence of intelligence continues 
 through all the stages of slowly extending brain disorder, and 
 it does not fail, even when the patient has passed into a state 
 of excitement, becoming unmanageable, so that forcible restraint 
 is necessary. He cannot govern himself, for he cannot com- 
 mand the restlessness of the sensitive system ; but he is sen- 
 sible of the greatness of the affliction which is upon him. Dr. 
 Bateman does indeed say that " he became imbecile, and quite 
 unmanageable ;" but the need for care in the interpretation of 
 " imbecility " is manifest when we read immediately afterwards 
 an account of Dr. Bateman's visit to the patient in the lunatic 
 asylum : — " 1868, July 9. I visited him to-day at the asylum, 
 and found him seated on a bench. He evidently recognised 
 me, but was quite unable to speak a single word, and he evinced 
 the greatest distress at his inability to converse with me." 
 Naturally he must at this stage be classed with the " imbecile," 
 but it would be hard to tell how much more an intelligent 
 being could do in order to show true appreciation of the posi- 
 tion in which he was placed than this man did, recognising a 
 friend who had done much for him, but speechless, agitated 
 under the feeling of restraint, and liable to increasing agitation 
 on account of his physical condition. I have seen highly in- 
 telligent and noble-minded men become confused in speech, 
 and lose masteiy over themselves in less trying circumstances. 
 It is affecting to consider what efforts are made by such 
 sufferers to articulate a monosyllable. Often they are thrown 
 into great excitement by the attempt. Dr. Hughlings Jackson 
 and Sir Thomas Watson both record cases in which patients 
 were unable to utter " No," and yet were brought to it under 
 the irritation of hearing gross misrepresentations as to their age, 
 1 Bateman's Aphasia, p. 65. 
 
312 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 or some other fact bearing on their own history or condition. 
 I am indebted to Professor Grainger Stewart of Edinburgh 
 University for a more pleasing illustration of this phase of 
 difficult effort, attended by utterance obviously automatic. 
 Dr. Stewart was demonstrating to his clinical class in the hos- 
 pital ward a case of aphasia, and was insisting on the distinc- 
 tion between voluntary and automatic speech. After testing 
 the aphasic patient in various ways, he asked him to say " No." 
 The utmost effort was made by the patient, but in vain. At 
 last he gave up the attempt, shook his head despondingly, and 
 said "No," thus automatically uttering the word, which he 
 could not accomplish by a voluntary effort. 
 
 The three classes of cases thus presented illustrate by vary- 
 ing forms of evidence how largely the intelligence depends upon 
 language for its exercise ; and, at the same time, how intelli- 
 gence finds exercise, even when use of language is denied. 
 Without intelligence language cannot be acquired ; the wide 
 range of use assigned to it shows how large an influence it 
 exercises in the work of intellectual progress ; and through all 
 stages of restraint upon the power of speech, it becomes clear 
 that intelligence is at work within the narrow limits imposed, 
 at work even with the result of throwing the whole body into 
 agitation on account of the conscious barrier to utterance. 
 
xi.] ACTION AND REACTION OF BODY AND MIND. 313 
 
 CHAPTEE XL 
 
 ACTION AND EEACTION OF BODY AND MIND. 
 
 The evidence already presented in illustration of the cor- 
 relative action of body and mind is sufficient to warrant 
 consideration of the influence of each upon the other. In 
 connection with sensation, motor activity, memory, and use 
 of speech, we have seen that the origin of action may be 
 either in the body or in the mind. Sensation results from 
 involuntary contact with external objects, or is caused by 
 determination of the mind in its search for knowledge. 
 Keflex action is accomplished by mechanism alone, that is, 
 by the action of the sensory apparatus on the motor ; volun- 
 tary use of the limbs or of the organs of sense is originated 
 and directed by intelligent purpose. There is a registra- 
 tion in brain tissue of acquired facilities, resulting from the 
 use of sensory and motor nerves ; and there is a preservation 
 of knowledge depending essentially upon intelligent discrimi- 
 nation of minute differences and their relations. Use of speech 
 involves a physical aptitude employed by the mind for expres- 
 sion of its knowledge of fact, its conceptions, or its inferences ; 
 but, even when vocal power has been lost, we find an action of 
 mind interpreting the words of others, and giving tokens of its 
 own exercise by such limited means of communication as 
 remain at command. 
 
 Thus, in all these forms of exercise, the body and the mind 
 are recognised as acting in distinct spheres, that is, eaeh is 
 found originating action, and securing its own results. The 
 contrast is so complete, that both action and results are 
 clearly distinguished. The satisfaction of organism, and the 
 search for knowledge, are exercises so different, that they are 
 in some degree antagonistic, bringing into activity two different 
 sides of our nature. Organism accomplishes much without the 
 
314 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 aid of mind ; intermediately, mind accomplishes, with the aid 
 of the body, much for which organism itself is insufficient; 
 and, in advance of this, mind, by a reflective process, reaches a 
 knowledge unattainable by sensory apparatus and the largest 
 stores of nerve energy. Mind and body constitute a unity in 
 the life of a single person. They are not independent of each 
 other, yet each can perform a different part, for which the other 
 is incompetent. They are inter-dependent, if I may use the 
 term, as the only one which adequately conveys the mutual 
 dependence which subsists, along with the power of acting 
 independently. But the inter-dependence varies in the course 
 of personal history, the dependence of mind upon body being 
 greatest at the early stages of life; the dependence of body 
 upon mind being greatest at the advanced stages. The consist- 
 ency of these two things is seen in this, that organism serves 
 higher ends in mature life. Spontaneous action of body is 
 most conspicuous in youth, but its activity is of a cir- 
 cumscribed range ; the voluntary action of mind is most 
 prominent in maturity, though the range of such activity 
 varies greatly in the history of individuals, and that in a ratio 
 proportionate to the degree in which the rational nature is 
 cultivated, and asserts ascendency over the body and material 
 existence beyond. In harmony with this ascendency of mind, 
 the dependent action of body is of much wider and more 
 important range than the bodily action characteristic of 
 early life. A pure independence of mind is not known in 
 our history ; but ascendency of mind over matter is quite con- 
 spicuous in the life of man. There are, indeed, many cases 
 in which an individual shows so much of the animal in his 
 conduct that he seems little raised above the animals ; but in 
 all such cases we recognise that the man is either imbecile, — 
 a sufferer because of undeveloped or wasted organism, — or he 
 is living a life unworthy of the higher nature he has, and which 
 is capable of controlling the lower nature, as no animal can 
 control its life. It is certainly impossible to construct a 
 science of human life, carrying a rational explanation of the 
 achievements of the race, while we treat only of organic action, 
 and do not recognise the ascendency of mind over matter. 
 The requirements are not met by a theory which represents 
 
xi. ] AC TION AND RE A C TION OF B OD V AND MIND. 3 1 5 
 
 the organic and rational features of our life as two phases 
 belonging to a single order of being. Professor Bain has said 
 that " one substance, with two sets of properties, two sides, the 
 physical and the mental, — a double-faced unity, — would appear 
 to comply with all the exigencies of the case." 1 A substance 
 with two sets of properties, and these directly antagonistic, as 
 represented by voluntary and involuntary actions, seems an 
 unwarrantable hypothesis. Man represents more than sensori- 
 motor apparatus, working an elaborate muscular system, by 
 means of stores of nerve energy. That which is highest in him 
 is not nerve force, and the further his " higher nature " is de- 
 veloped, the more obvious does this become. 
 
 In accordance with this representation, it will be found pos- 
 sible to trace, by clearly marked lines of interaction, the influence 
 of body upon mind and mind upon body. We are familiar 
 with the fact that a disturbed bodily condition is an effectual 
 hindrance to the action of intelligence. Suffering from indi- 
 gestion will depress a man so completely as to sadden his life, 
 and make him feel unequal to the task of concentrated intel- 
 lectual effort. A severe bilious attack will effectually stop one 
 in any course of study, however deeply interested he may be 
 in it. A violent blow on the head will deprive a person of 
 consciousness, and lay him prostrate for days, leaving him 
 dependent on friendly hands for the supply of food, which he 
 receives without being aware of it. In such a case, life is 
 sustained only by careful nursing, which carries it through 
 a crisis, out of which the sufferer comes utterly weakened, 
 not knowing what has happened, and testifying that these 
 intervening days have been an entire blank in his experi- 
 ence. These are familiar facts, closely connected with the 
 present inquiry. By many they are regarded as evidence that 
 mental existence is not distinguishable from bodily. The 
 argument may be summarised in a few sentences. Disorder 
 of the digestive process, or disease of the liver, may greatly 
 restrict mental action, showing that by disturbance of func- 
 tional activity in other physical organs, the brain can be in- 
 directly restrained, the action of intellectual power weakened, 
 and, in more extreme cases, " personal experience" temporarily 
 1 Mind and Body, p. ] 96. 
 
316 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 terminated. It seems to follow that intellectual exercises are 
 the result of organic processes. Further, by direct injury of 
 the brain itself, as the result of concussion, or fracture of the 
 skull, and indentation of the bone or insertion of other hard 
 substance, all exercise of thought may be brought to an end for 
 a time, and the possibility of resuming intellectual activity 
 depends upon restoration of the brain to a normal condition. 
 Combining the evidence from indirect action of disease in 
 other organs, with that from direct injury to the brain itself, it 
 is argued that what we call " mental action " is a purely organic 
 process. This. argument is regarded by some as conclusive, 
 apart from all other evidence, and on that account it deserves 
 consideration. 
 
 In order to estimate the argument at its true worth, we 
 must distinguish exactly the several positions it includes, and 
 afterwards ascertain how much it leaves unsolved. These posi- 
 tions are the following : — 
 
 1. Disturbance of other organs, such as the digestive, in- 
 volves disturbance of brain. The brain, while performing 
 distinct functions, depends for its own efficient action upon 
 other organs performing healthily their functions. 
 
 2. Disturbance of an organ such as the brain, resulting from 
 disordered action of another, clearly proves that the two are 
 closely united in a common organic system. Thus the nutri- 
 tive system is dependent on the nerve system, and that again 
 on the nutritive. 
 
 3. Direct injury to the brain, from whatever cause, and in 
 whatever form, occasions disturbance of its functional activity. 
 Paralysis, sensory or motor, or both together, will supervene, 
 according to the locality and extent of injury. Examples do, 
 however, occur of injury, more commonly when restricted to 
 one hemisphere, without any experience of personal disadvan- 
 tage ; but the rule is otherwise. 
 
 4. Disturbance of brain, whether by indirect or direct in- 
 jury, generally involves disturbance of what is called " mental 
 activity." There is no part of the sensory system, no part 
 of the motor, no co-ordination of centres belonging to either, 
 no acquisition of facility regulated by the cerebrum or brain 
 proper, which is not related to mental activity. The sympa- 
 
XI.] ACTION AND REACTION OF BODY AND MIND. 317 
 
 thetio system stands in a somewhat different relation, not 
 being directly under control of the will. It is therefore not 
 directly related to mental action, as the sensori-motor system 
 is ; but it is indirectly related, in accordance with the first 
 position in this argument. On these grounds, I think it is 
 clearly to be granted that, as a rule, brain disturbance carries 
 with it disturbance of mental action. 
 
 5. From these data we cannot infer that mental activity is a 
 purely organic process. It is shown that the cellular tissue of 
 the brain depends for the evolution of nerve energy on regular 
 and healthy blood supply, and that the whole mass of nerve 
 fibres depend for functional activity upon evolution of nerve 
 energy. It is further shown that, as all functional activity of 
 the nerve system -is dependent on evolution of nerve energy 
 from pabulum supplied, the voluntary and intelligent use of 
 the sensory and motor system illustrates the general rule. It 
 is proved that the brain must be in an efficient state if it is to 
 be the organ or instrument for accomplishing rational ends. 
 But nothing more than this is shown. On the other hand, 
 there are many facts to demonstrate that intelligence can prove 
 its superiority to the defects of organism. The beginning of 
 personal effort is an intelligent conception, with deliberate deter- 
 mination to accomplish a definite end. There is not evidence 
 to uphold the theory that these acts can be accounted for by 
 full development of the frontal lobes. Minds deprived of the 
 ordinary organic helps have demonstrated their power to 
 triumph over their restraints, and achieve what is not ordi- 
 narily accomplished. Starting in an educational course with 
 the consciousness of restraint equal to existing organic dis- 
 advantages, the sufferers have shown a power to master their 
 difficulties, bringing intelligence and correlated nerve centres 
 into vigorous exercise, with a minimum of aid from the sensory 
 system. Illustration of this is afforded by the case of Laura 
 Bridgman (p. 296), and a multitude of cases involving brain 
 disease, of which examples will be given hereafter. There is 
 no acute suffering, and no form of brain disease which does 
 not more or less injuriously affect the' action of mind, but 
 even under such restraint, mental action can proceed ac- 
 cording to recognised intellectual law. Functional activity 
 
318 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 is restrained in the nerve centre, and mental activity is in 
 consequence to some extent restrained also, but the mental 
 restraint is not equivalent to the physical injury. 
 
 This will appear still more clearly if the negative positions 
 involved in the argument are properly considered. Granting 
 that an intimate relation does subsist between the brain and 
 other physical organs, and that brain functions are retarded by 
 a restraint placed on digestive functions, we must observe what 
 positions are excluded under the argument. 
 
 1. The intimate relationship proved to subsist between the 
 digestive organs and the brain does not involve any confusion 
 of the functions belonging to the related organs. 
 
 2. Eestraint upon functional activity of brain, through dis- 
 order of some related organ, is only temporary, and does not 
 involve loss of functional power in the brain. 
 
 An exact analogy may be traced in the relations of brain and 
 mind. Let us pass over to the standpoint of the theory that 
 mind is a higher order of being connected with the brain, de- 
 pendent for its own proper activity on healthy action of the 
 brain, and operating through the brain as its only organ of 
 communication with the sensory and motor system. Though 
 disorder of the digestive organs involves disturbance of brain, 
 it does not therefore follow that the stomach can perform 
 the functions of the brain. And just so, though disorder 
 of brain involves disturbance of mental action, it does not 
 therefore follow that the brain can perform the functions of 
 mind. If then it has been shown, by study of our experi- 
 ence, that the sensory and motor apparatus are insufficient to 
 explain sensation and voluntary motion, and that we must 
 acknowledge a higher order of existence if we are to account 
 for intelligent discrimination and voluntary determination, no 
 doubt is thrown on this conclusion by the fact that brain dis- 
 order occasions a check to mental activity. The unity of our 
 nature implies that disturbance of any vital organ will involve 
 disturbance for the whole being, and the closeness of relation 
 between brain and mind in respect of functions — a relation 
 much more intimate than between the stomach and the brain 
 — makes it certain that disturbance of brain action must in- 
 volve disturbance of mental action, which is constantly con- 
 
XI.] ACTION AND REACTION OF BODY AND MIND. 319 
 
 cerned with sensory and motor activity. The action of body 
 upon mind, so far from being inconsistent with the theory 
 that the mind is a higher order of existence fulfilling distinct 
 functions, in reality confirms that theory, illustrating at once 
 the intimate relations of the two, and their distinctness of 
 nature and function. 
 
 Beyond this range of inquiry there are several fine and 
 delicate distinctions connected with the facts of brain disease 
 which must be reserved for a stage of investigation slightly in 
 advance of the present. 
 
 Passing now to the other side of the question, it becomes 
 needful to consider what evidence human life affords of the 
 action of Mind upon Body. If within our nature there is 
 duality of being, involving the union of two distinct forms of 
 existence, there must be clear evidence of the action of mind 
 upon our physical organism. That our nature is a unity, is 
 granted ; and it has been admitted in the preceding portion of 
 this chapter, that everything which disturbs the sensory or 
 motor system must exert some perceptible influence upon the 
 mind also. But the distinctive characteristics of mind, and its 
 functions as the governing power in human life, make it evident 
 that there should be not only some degree of proof, but over- 
 whelmingly strong evidence that mind has an ascendency over 
 the body, even though it be an ascendency restricted by the 
 laws of physical life. The laws of physical and mental 
 activity so differ, that the physical nature cannot perform the 
 functions of the mental, nor can the mental perform the func- 
 tions of the physical nature. Clear as it is when we speak of 
 our " personal life," that we make account of the body as part 
 of ourselves, it is no less certain that we regard it as a sub- 
 ordinate part. It is recognised as a form of existence allied 
 to physical nature generally, and dependent on physical exist- 
 ence around it for the means of its subsistence. But each in- 
 dividual regards his body as part of himself, and finds hourly 
 evidence of the fact in the extent to which bodily functions are 
 made to do service in accomplishing ends voluntarily selected 
 by the rational nature. In accordance with this subordination 
 of bodily existence, we see that mutilation and consequent 
 deformity of body may occur on account of the many acci- 
 
320 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 dents to which the physical organism is exposed. Such muti- 
 lation we invariably regard as a serious injury, but still a 
 subordinate injury not involving a true deformity of the life. 
 We do, indeed, speak of "personal attractions," meaning to 
 refer only to bodily appearance ; and the expression is strictly 
 accurate, inasmuch as we admit that the body is part of the 
 person. Disfiguration of the body we recognise as a loss in 
 " personal attractions," for all admire the beauty and symmetry 
 of the body ; but we do not for a moment allow that a real 
 deformity of life is involved, as there is when a man gives him- 
 self up to a life of self-indulgence, sacrificing the best interests 
 of himself and others for animal pleasures. There is a greater 
 and a less — a higher and a lower — in human life, and the true 
 deformity of nature and life is that only which touches the 
 higher, making a man's conduct less a rational life, and more 
 a merely animal life, than it is naturally fitted to be. In har- 
 mony with these considerations we acknowledge that a lofty 
 and pure mind gives dignity and attraction to the body itself, 
 as Plato has said in his argument as to the superiority of edu- 
 cation over gymnastic, " not that the good body improves the 
 soul, but that the good soul improves the body." 1 
 
 The evidence that mental activity has a controlling power 
 over the body is overwhelmingly abundant. There is no 
 philosophy of human life possible, unless this vast range of 
 facts be deliberately considered. The more fully this evidence 
 is arranged according to its varying phases, the more con- 
 spicuous will appear the wide range of separation between 
 man and animal, as well as the distinctiveness of mental 
 activity, and the speciality of the laws under whiqh such 
 activity takes place. 
 
 The proof to which reference is here made includes facts 
 which may be classified under the following heads, — rational 
 control over our bodily movements; deep feeling injuring 
 bodily health ; mental occupation modifying experience of 
 suffering; mind aiding recovery from disease; mental deter- 
 mination extending the range of endurance under toil or pain. 
 Evidence under some of these heads has already been adduced, 
 as on voluntary control of motor activity (p. 242, and onwards); 
 1 Republic, Book iii. 403. 
 
XI.] ACTION AND REACTION OF BODY AND MIND. 321 
 
 and the power of personal determination to prevent shrinking 
 of the muscles during a surgical operation (p. 239). To these 
 divisions it is not needful to return. It is, however, de- 
 sirable to adduce here some additional illustrations, capable of 
 being readily tested. The requirements of the present argu- 
 ment will be amply met by including this portion of confirma- 
 tory testimony under the two heads, power of emotion, and 
 power of intellectual interest. The difficulty is not to supply 
 evidence, but to select from the overwhelming mass examples 
 sufficiently representative. 1 
 
 1. Power of emotion over the bodily condition. — Emotions such 
 as fear and joy exercise a powerful influence upon the body. 
 In human life physical excitement is often a consequence of 
 mental excitement produced by personal exercise of thought. 
 The phenomena which illustrate this are peculiar to human 
 life, not being found in the experience of animals. If we dis- 
 tinguish carefully the causes of our emotions, it is placed 
 beyond doubt that in some cases emotion is roused by the 
 action of external objects, in others by the exercise of the 
 mind alone, while in a third class of cases there is a com- 
 bination of both influences. Such classification, established 
 on a multitude of well-authenticated cases, strongly supports 
 the position that mind and body, while they together constitute 
 unity of nature, are distinct forms of existence, acting and 
 reacting upon each other. 
 
 Fear is often occasioned by external objects of an unusual 
 and threatening aspect. The lowest phases of such experience 
 illustrate the analogy between animal and human life. The 
 horse and his rider may be startled by the same object, and the 
 experience in both cases is the result of nerve sensibility. But 
 we make a transition which separates human from animal life 
 when we observe that man is liable to experience fear because 
 of expectation of danger, apart from local associations. A horse 
 running regularly along the same road may have apprehension 
 
 1 Reference may be made to Illustrations of the Influence of the Mind upon 
 the Body in Health and Disease, by Daniel H. Tuke, M.D. ; The Use of the 
 Body in relation to the Mind, by George Moore, M.D. ; The Power of the Soul 
 over the Body considered in relation to Health and Morals, by George Moore, 
 M.D. 
 
 X 
 
322 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 at a particular turn of the way where he has previously been 
 alarmed. "Within such limits as are indicated by local asso- 
 ciations with past experience, animal life and human have 
 much in common. But the distinctive action of intelligence, 
 involving its possessor in an enlarged experience of fear, is 
 seen when, by reflecting upon possible occurrences in the 
 future, apprehension is awakened, which throws the body into 
 agitation, though there is no external cause of alarm present to 
 the view. Trouble of this kind does not disturb an animal's 
 peace. 
 
 The power of expectation is illustrated by experience of vertigo 
 or giddiness, solely as the result of apprehension of danger. When 
 speaking of the explanation of giddiness during rotatory motion 
 afforded by the structure of the third or innermost chamber of 
 the ear (p. 75), I took occasion to remark that it did not ex- 
 plain a similar uneasy experience without any rotation of the 
 body. There are many unaccustomed to be on a height, who 
 at once become giddy on the edge of a precipice, and even 
 tremble as they walk on a road of sufficient breadth to provide 
 for safety, when there is a chasm on one side. Simply on 
 account of knowing the height reached, and being aware that 
 part of the road to be travelled skirts the face of the rock, their 
 body is thrown into agitation. When the point regarded with 
 apprehension has been reached, and the mind contemplates the 
 consequences of a fall headlong, giddiness sets in, the limbs 
 tremble, and even the slowest progress becomes a source of 
 distress. No animal climbs the mountain steeps with such 
 apprehension, or stands on the trackless slope regarding it as a 
 " giddy height." On the other hand, the person who is liable 
 to the experience of giddiness escapes it according to the degree 
 in which he is able to persuade himself that no great danger is 
 incurred. No explicitness of testimony from others will secure 
 this result, since the sufferer from giddiness is well aware that 
 he is liable to uneasiness which others do not share. But if, 
 by personal observation and reflection, he satisfy himself that 
 there is in reality no serious risk, the giddiness is in some 
 degree abated, and body and mind are gradually restored to a 
 measure of calm. As the result of experiencing this uneasy 
 feeling to a much greater extent than I could have wished, I 
 
XI.] ACTION AND REACTION OF BODY AND MIND. 323 
 
 am familiar with the facts here recorded, and have had reason 
 to regret that there is such evidence of the power of thought 
 and imagination to produce physical disturbance. 
 
 Closely related with such facts in the history of human fear 
 is the agitation often attendant on a sudden shock to the nerve 
 system, leading to the imagination of suffering which has no 
 reality. An animal gives evidence of suffering only accord- 
 ing to the pain endured. There is, indeed, diversity in the 
 degree of sensibility among animals, naturally causing con- 
 siderable diversity of result under similar forms of suffering. 
 On an icy road, where there is risk of falling, one horse becomes 
 much more nervously excited than another. Difference of 
 nervous excitability in the two cases explains the contrast. 
 But animals are not troubled with imagination, and do not cry 
 out as if in anguish when they are unhurt. Such outcry is, 
 however, common enough in human history under sudden 
 shock. Professor Bennett, of Edinburgh University, has left on 
 record a case reported to him by the chemist who had witnessed 
 it. A butcher, working in the Market of Edinburgh, was in the 
 act of hanging a heavy piece of meat on a sharp hook, when 
 his foot slipped, and he was caught by the arm and hung sus- 
 pended in the greatest anguish. He was taken down and 
 carried across to a chemist's shop on the opposite side of North 
 Bridge Street, where the case was at once attended to as one 
 of urgency. The surgeon proceeded to cut open the sleeve of 
 the man's coat, the sufferer crying out in great agony as this 
 was done, yet, when the arm was exposed, it was found that 
 the skin had not even been scratched. The hook had pene- 
 trated no farther than the coat. 1 
 
 Dr. Noble has recorded a similar case in the experience of 
 Monsieur Boutibonne, a literary man, who served in Napoleon's 
 army, and ■ was engaged " at the battle of Wagram, which re- 
 sulted in a treaty of peace with Austria, in November 1809." 
 Towards sunset, when reloading his musket, he was shot down 
 by a cannon ball. He felt as if the greater part of both legs 
 had been carried away, and all night he lay helpless, not daring 
 to move, lest he should bleed to death. At early dawn, a 
 medical officer came to his help. To the question, " "What 's 
 
 1 The Mesmeric Mania of 1851, by Professor Bennett, p. 15. 
 
324 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 the matter, my comrade?" M. Boutibonne replied, "Oh, touch 
 me gently, I beseech you ; a cannon ball has carried away my 
 legs." The doctor examined his legs, and with a laugh bade 
 him get up, as there was nothing wrong, when the sufferer 
 leapt to his feet in amazement. The cannon ball had carried 
 away the ground underneath his feet, and he had fallen into 
 the trench which had been suddenly opened. 1 
 
 These examples may suffice for illustration, without extend- 
 ing references to include examples of the power of grief, or the 
 influence of sudden experience of great joy. Under each head 
 distinct evidence can be presented demonstrating the power 
 which purely mental action exercises over the bodily state. 
 
 2. Power of intelligent interest to affect the bodily condition. — 
 Interest in objects and engagements, apart from varying con- 
 ditions of health, contributes largely to healthy action of the 
 body, escape from pain, and restoration from disease. Every 
 medical practitioner recognises such facts, and every patient 
 who has been for any considerable time under treatment knows 
 how much his state of health is influenced by his mental occu- 
 pation. If he is interested, occupied now with one subject of 
 reflection, and again with another, turning with satisfaction 
 from engagement to engagement, and rising into ranges of 
 meditation, at once calm and elevating, the body itself is kept 
 in a greater degree of rest, and the conditions are most favour- 
 able for recovery. A raging fever, or an acute form of suffer- 
 ing, may prevent the mind from maintaining concentrated in- 
 terest in objects without, or subjects of meditation; but, if 
 such concentration be possible, there is, by a purely mental 
 action, a distinct contribution towards recovery from disease. 
 
 Many examples have been recorded of temporary escape 
 from acute suffering under the influence of absorbing mental 
 interest. I content myself with a single illustration. During 
 the intense excitement in Ireland awakened by the case of 
 Daniel O'Connell, Lord Anglesey, having gone over to Ireland, 
 was so roused by it as to escape during a lengthened period 
 from the suffering of tic douloureux, to which he was at other 
 times a martyr. Mr. Greville narrates the circumstances in 
 the following manner : — " It is an extraordinary thing, and tlie 
 1 Tuke's Influence of the Mind upon the Botli/, p. 131. 
 
xi.] ACTION AND REACTION OF BODY AND MIND. 325 
 
 most wonderful I have ever heard of the power of moral causes 
 over the human body, that Lord Anglesey, who has scarcely 
 been out of pain at all for years during any considerable in- 
 tervals, has been quite free from his complaint since he has 
 been in Ireland. The excitement of these events, and the 
 influence of that excitement on his nervous system, have pro- 
 duced this effect. There is a puzzler for philosophy, and such 
 an amalgamation of moral and physical accidents as is well 
 worth unravelling for those who are wise enough." 1 Under 
 excitement, diminished sensibility to pain is common both in 
 animal and human life ; but only in human life does it appear 
 as the result of continuous interest. It must, however, be ad- 
 mitted that our knowledge of the action of the intellect and 
 emotions upon the nerve system, and upon the organs of secre- 
 tion, is not yet so advanced as to enable us to present an ade- 
 quate explanation of such results as those described in this 
 case, and in many cases of a like kind. But the facts are 
 familiar in human experience, and they illustrate the truth 
 that the regulation of thought and attendant feeling is largely 
 influential in promoting health, while neglect or surrender of 
 such control may prove seriously detrimental. 
 
 These two facts stand indubitable : Disturbance of bodily 
 functions can retard intellectual action, — Thought, with its 
 attendant emotion, can lower or quicken the vitality of the 
 physical organism. As correlated facts they are strongly con- 
 firmatory of the position that there are in human nature two 
 forms of existence acting and reacting upon each other. 
 
 1 Journals of the Reigns of George iv. and William IV., vol. ii. p. 109. 
 
326 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 CHAPTER XII. 
 
 WEARINESS, SLEEP, AND UNCONSCIOUSNESS. 
 
 In tracing the relations between mind and brain, the phy- 
 sical weariness attending on mental effort must be considered. 
 The person engaged in manual labour, and the man sitting in 
 his study thinking out a complex problem, both grow weary. 
 The facts are undoubted, and importance must be attached to 
 them. There are some who, on the single ground that exces- 
 sive lassitude follows upon protracted study, argue that thought 
 is thereby shown to be a function of brain. Others, seeing 
 that such a conclusion is extreme and unwarranted, infer, on 
 the same data, that there is no action of mind without attend- 
 ant brain action. This less extreme position is still doubt- 
 ful. It has been very generally assented to by physiologists, 
 and may be true, but it has not yet been demonstrated ; and 
 it is desirable, in a matter so intricate as the relations of mind 
 and brain, that we go no further than we are warranted by 
 clearly ascertained facts, leaving ourselves open for additional 
 light which may be thrown on the functions of the brain as 
 the result of continued research. 
 
 The facts connected with the physical exhaustion attendant 
 on severe study are sufficiently definite to afford a distinct 
 department of evidence. "While, however, we are here to pro- 
 ceed upon a recognised distinction between physical and 
 mental labour, we must guard against an unwarrantable 
 severance of muscle and brain in connection with human effort. 
 It is customary to speak of " manual labour " and of " brain 
 work," as if they were two entirely different things. But the 
 supposed line of separation between these two does not exist. 
 If we distinguish between "manual labour" and "mental 
 work," there is a wide difference. Bait there is no " manual 
 labour " which is not at every moment of its continuance real 
 
xii.] WEARINESS, SLEEP, AND UNCONSCIOUSNESS. 327 
 
 " brain work," as the preceding investigations have amply- 
 illustrated. The commonest work of the hands cannot be done 
 without a draft upon the nerve energy supplied by the brain. 
 All human labour is brain work, and all the work done by the 
 lower animals in the service of man is also brain work. The 
 best developed muscular system, with all the latent energy 
 which belongs to it, is dependent upon its relation to the brain 
 for the accomplishment of its work. We may, indeed, with 
 strict accuracy say that the muscular system accomplishes 
 what the brain itself cannot do, for there is a degree of mus- 
 cular energy liberated by the nerve fibres greater than the 
 nerve energy which sets it in motion (see pp. 79, 199). But 
 the source of all manual labour, and all muscular effort of what- 
 ever sort, is not lower than the brain. It is therefore apt to be 
 misleading, if we speak of manual labour as if it stood in direct 
 contrast with brain work ; or, on the other hand, if we speak 
 of mental effort as if it were distinctively "brain work. 
 
 Thus mental work and brain work are far from being contem- 
 poraneous and co-extensive. If there is no manual labour with- 
 out brain work, it is clear that there is a very large amount of 
 brain work which involves very little mental effort. In strict 
 accuracy, it must be said that in the case of those whose occu- 
 pations are restricted to the lowest forms of manual labour, by 
 far the greatest proportion of brain work in their life is devoted 
 to muscular effort. There may, therefore, be a lifetime of brain 
 work with comparatively little exercise of thought. This may 
 be illustrated by the limited vocabulary of the man who has 
 never been taught to read. It has been reckoned that the 
 whole words in regular use by such a man, and found by him 
 sufficient to meet the requirements of his daily life, are not 
 greatly over three hundred, while the moderately educated man 
 has several thousands in regular use, and the vocabulary of 
 highly educated persons is vastly wider (p. 277). While, how- 
 ever, there may be constant brain work, with comparatively 
 limited exercise of intellectual power, it is clear that mental 
 activity involves a large degree of brain exercise, and is quickly 
 attended by a sense of physical weariness. In attempting to 
 interpret the facts, it should be noticed that there is common 
 ground to a considerable extent occupied by those who give 
 
328 THE RELA TIONS OF MIND AND BRAIN. [chap. 
 
 chief prominence to the power of organism, and those who 
 assign clear ascendency to mind. Whatever be the scientific 
 explanation offered of intellectual action involving discrimina- 
 tion, inference, imagination, and rational government of our 
 dispositions, it is admitted on all hands that a large amount of 
 brain action is connected with the various phases of intellectual 
 activity. The diversity of opinion on this matter is far from 
 being anything so serious as a positive assertion of exclusive 
 brain action on the one side, and a thoroughgoing denial of 
 such action on the other. The range of discussion, and conse- 
 quent difference of opinion, is greatly more restricted. It is 
 freely granted on both sides that there is a large amount of 
 nerve action connected with mental activity, and the difference 
 of opinion is concerned wholly with the degree to which this 
 has been demonstrated, and consequent physical weariness has 
 been explained. 
 
 To avoid needless complications, it is desirable to enumerate 
 the forms of brain action which must be considered as gener- 
 ally attending on the more ordinary mental exercises. They 
 may be briefly stated thus: (1.) action of the special senses, 
 and of the general tactile sense ; (2.) action of the muscles 
 concerned in the management of these senses, and specially of 
 the organs of sight ; (3.) co-ordination of sensory and motor 
 apparatus required for use of the senses ; (4.) action of sensory 
 centres consequent upon use of the Imagination (p. 273), in 
 part a renewal of sensory impressions, or a movement of the 
 sensory cells consequent upon stimulus which imagination sup- 
 plies ; (5.) sensory and motor action consequent upon the 
 stimulus coming from mental emotion, such as weeping, facial 
 expression of sadness or sympathy. These are generally recog- 
 nised phases of brain action closely connected with mental action. 
 If only allowance be made for a possible diversity of opinion 
 under the fourth head, it may be regarded as almost undis- 
 puted that all these attend on " mental activity." Thus the 
 inquiry as to the explanation of physical weariness follow- 
 ing upon the action of the mind, starts from definite physio- 
 logical ground, with an ample store of facts. All these phases 
 of brain action just enumerated, as they involve active use of 
 brain energy, imply transformation of energy, consequent waste 
 
XII.] WEARINESS, SLEEP, AND UNCONSCIOUSNESS. 329 
 
 of brain substance, and inevitable sense of exhaustion. With 
 these facts before us, we can reach some conclusions as to the 
 weariness attending on mental activity. 
 
 First, There is large use of both sensory and motor apparatus 
 in connection with all the ordinary forms of intellectual activity. 
 — In observation of external objects, in guidance of the hands, in 
 listening, in reading, whether silently or aloud, and in address- 
 ing others, there is continual nerve action, sufficient to account 
 for the weariness experienced. The intellectual exercise may 
 interest and even delight us ; and we grow weary, not because 
 the mind's interest has come to an end, but because physical 
 discomfort is experienced on account of the need for physical 
 rest and refreshing. In reasoning on this subject, due allow- 
 ance has not been made for the extent to which nerve action 
 is maintained while we are engaged almost exclusively in what 
 are commonly called "mental exercises." Observe a person 
 listening attentively, and you will soon become convinced that 
 it is not merely the auditory nerves and the interpreting mind 
 which are at work. You will notice the listener's eyes watch- 
 ing the lips of the speaker, and the expressions which flit 
 across the face, glancing at times rapidly to others of the audi- 
 tory, and coming quickly back again so as to miss nothing the 
 speaker is saying or revealing by his countenance, sometimes 
 turning to the ceiling or to the window when something has 
 been said which appears doubtful, and again returning to mark 
 what is being said. There is a large amount of nerve action in 
 all this, leaving no ground for wonder that the brain at length 
 grows weary. So in reading there is a constant strain upon 
 the eyes. Or take the case of the public speaker, and you may 
 observe from his eyes alone how large a portion of the sensory 
 system is kept under strain. He not only thinks of what he 
 is about to utter, and in what language to express himself, but 
 he is turning his eyes first to one side of the room, and now to 
 the other, — directing a passing glance to one face, again to a 
 second, and again to a third. He feels any expression of 
 approval or dissent, notices when his utterances awaken in- 
 terest or call forth some sign of disapproval. Thus it is that a 
 "reat part of the nerve system, both on its sensory and its 
 motor side, is kept in very lively exercise, and when he sits 
 
330 THE RELA TIONS OF MIND AND BRAIN. [chap. 
 
 down it is neither exclusively the vocal effort nor the intel- 
 lectual exercise which accounts for the sense of weariness he 
 experiences. In course of an address of quite moderate length 
 there have been hundreds of currents of nerve energy streaming 
 outwards and inwards, readily accounting for a large degree of 
 weariness at the nerve centre. But such weariness is not to 
 be attributed in any considerable measure to the intellectual 
 action involved. Such intellectual effort, in the quietness of 
 one's own room, and without any utterance of thought, would 
 certainly have been followed by weariness, but not to that 
 extent of physical exhaustion which a public speaker is apt to 
 feel, and which, as a rule, is proportioned to the extent to which 
 the speaker takes intelligent note of all that occurs while his 
 words fall on the ears of others. 
 
 Second, All thought proceeds, to a large extent, by use of 
 language, and thus seems to involve activity of the cells concerned 
 with the acquisition and use of language and speech. — That 
 language and speech are acquirements is admitted, and also 
 that the acquisition in both cases implies constant use of sensory 
 and motor cells. The artificial signs used to represent sounds, 
 and the combinations of these into words, need to be acquired 
 by sight, and also by vocalisation. In the case of the blind, 
 we have seen that the acquirement of language depends on 
 careful use of the sense of touch ; in the case of deaf-mutes, on 
 use of sight and visible signs ; in the case of those who have 
 lost both sight and hearing, upon peculiarly minute and com- 
 plicated processes, by use of the tactile sense (p. 297). If the 
 acquisition of language is an important aid to the development 
 of intelligence, we know further that the extent to which 
 written and spoken language is employed, becomes to some 
 degree a measure of the intelligence of the individual. The 
 higher the intellectual activity of the person, the wider the 
 range of language employed by him, and consequently so much 
 the larger the demand which his intelligence makes on the 
 sensory and motor cells belonging to the centres by which 
 language and vocalisation are utilised. There are many familiar 
 facts which support this view, and give additional force to the 
 argument establishing demand on brain activity as an accom- 
 paniment of intellectual effort. All thought, as it proceeds, 
 
xii.] WEARINESS, SLEEP, AND UNCONSCIOUSNESS. 331 
 
 involves some use of words or selected signs to give definite- 
 ness to it ; the more carefully a man weighs his thoughts, the 
 more he needs to formulate them in exact sentences, involving 
 a still larger use of language; in order still further to add force 
 to his thought, and give emphasis to the leading features of 
 it, a man is often heard to utter, more or less audibly, the 
 very words selected by him ; and all such exercise, besides 
 a large use of memory, draws upon the results of physical 
 sensibility in the past, and this, as it is a recalling of sensory 
 impression, may be regarded as somewhat akin to renewal of 
 the action of the sensory cells concerned in the previous experi- 
 ence. All these exercises involve a demand on brain activity 
 as an accompaniment of thought, in accordance with the theory 
 that thought itself is the product of a power altogether superior 
 to brain. And all these forms of brain action, taken along 
 with the work which is constantly being done in sustaining 
 the functions of vital organs depending on the nerve centre, 
 are sufficient to account for the weariness which attends on 
 ordinary exercise of thought. If there be in addition a demand 
 for dexterity of manipulation, as in writing, engraving, drawing, 
 painting, or mechanical contrivance, there is a proportionally 
 greater demand on the nerve energy of the brain, and conse- 
 quently the sense of weariness is experienced more quickly, 
 or is more oppressive at the end of the same measure of time. 
 
 Third, Concentrated, thought makes a severer demand upon all 
 the forms of brain action connected with ordinary thought, and 
 so quickens and increases the exhaustion of nerve energy. — The 
 more concentrated the exercise of thought, the more completely 
 does the mind depend on language. We cannot content our- 
 selves with a few signs standing as representations of certain 
 things or stages of thought. The several elements of our 
 reflection require to be more exactly formulated, the nicer dis- 
 criminations of meaning need to be marked, and for this we 
 are dependent on words, the use of which seems constantly 
 connected with brain action. This greater exactness becomes 
 matter of mental effort, but it makes special demand upon the 
 acquisitions of the nerve centre. There is, indeed, one respect 
 in which it may be said that the demand on nerve action is 
 diminished. In order to secure mental concentration, we draw 
 
332 THE REI.A TIONS OF MIND AND BRAIN. [chap. 
 
 off our attention from things external, restricting, as far as pos- 
 sible, the use of the senses, in order to escape the distractions 
 apt to be experienced. We seek retirement and quiet, and 
 even when these are found we may close our eyes, the better to 
 avoid distraction from moving objects. All this seems volun- 
 tary restriction upon brain action ; and at first sight it might 
 appear as if, on the theory of a higher nature being concerned 
 in purely intellectual effort, less demand should be made on 
 nerve energy, and accordingly a slighter sense of weariness 
 should be experienced; whereas it is well known that the 
 exhaustion is great which attends on such thought. But a 
 little consideration will show that such abstraction does not 
 imply a mere release, or period of inactivity for the nerve 
 centres concerned with the management of the special senses. 
 On the contrary, the process of abstraction is directly connected 
 with management of the body, and, as it is a management not 
 by any means usual, it really involves a very special form of 
 brain action, certain to be more than ordinarily exhausting. 
 What is required for success in concentration is a species of 
 deliberate inhibitory action, involving a considerable strain 
 upon the nerve system. We do not simply leave the special 
 senses to themselves. That is done when we have no self- 
 selected occupation to engross the attention, and the mind is 
 left to go "wool-gathering." This is the simplest and most 
 easy of exercises, which should take a long while to weary a 
 person. To leave the senses open to every kind of impression 
 that can be made upon them, allowing the mind to be alto- 
 gether under guidance of our sensibilities, is the easiest of 
 occupations. But to concentrate the mind upon some abstruse 
 subject, to be carefully thought out in all its aspects, is not 
 only high mental work, but it implies hard physical work, in 
 order that what is intellectual may be carried through with 
 success. It implies a deliberate and well sustained guard put 
 upon the senses, that they may not prove hindrances to us. 
 Every one who has trained himself to such work knows well 
 that it is physical work as well as mental. And even when 
 one has attained a considerable measure of skill in such exer- 
 cise, it is not found to hold true that the eyes can by-and-by 
 be left to roam about, and the ears be set open to every sound 
 
xn.l WEARINESS, SLEEP, AND UNCONSCIOUSNESS. 333 
 
 that floats in the air. It is altogether otherwise. Eigid control 
 over the senses cannot be relaxed even by the most successful 
 student, and hence it is that there must be sense of great 
 weariness as the result. 
 
 These considerations lead naturally to the conclusion that 
 only a limited portion of time each day can be appropriated to 
 such employment. And, as all nerve action involves weari- 
 ness, with demand for nourishment and rest, we are naturally 
 led to consider the phenomena of sleep as these are concerned 
 with the relations of mind and brain. How sleep is induced, 
 and what physiological changes result, are questions of much 
 difficulty, on which a great deal has been written. "We 
 do not yet seem to be in possession of generally accepted con- 
 clusions on the subject, and I shall be content to deal with 
 the phenomena of sleep as these come under ordinary obser- 
 vation. 
 
 Sleep implies rest primarily and specially to the sensory 
 and motor systems, and through these to the general muscular 
 system. It is thus essentially a physical state, providing for 
 repose of the body. The whole body obviously shares in the 
 advantage arising from a cessation of action and a uniformly 
 calmed condition, excepting only those vital organs controlled 
 by the sympathetic nerve system, which work without ceasing 
 by night or by day. While the entire motor system, excepting 
 the sympathetic, shares equally in the rest, there is some 
 diversity as to the degree of inactivity secured for the sensory 
 system. As sensibility or excitability of the sensory nerves 
 is a uniform condition of a healthy state, it is maintained 
 through sleep, and liable to be acted upon from without. The 
 general tactile sense is that most liable to impression, as it is 
 apt to be influenced by changes of posture, exposure of any 
 part of the body, and changes of temperature. In this way, 
 the reflex power of the motor system may be brought into use. 
 Of the special senses, the sense of Sight, the most restless and 
 active of all during waking hours, has the fullest advantage 
 from slumber. The eyes give clearest indication of drowsiness, 
 and when the eyelids are fast the state of sleep is established. 
 The other special senses, particularly smell and hearing, are 
 more exposed to external influence. The peripheral organs 
 
334 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 of these two senses are so placed that the entrance conducting 
 to the sensitive surface is continually open. Smell and Hear- 
 ing are thus the sentinels on guard, ready to give warning of 
 any disturbance or danger. Such are the essential modifica- 
 tions of the sleep state, affecting variously different portions of 
 the nerve centre. Making allowance for these, and for the 
 casual forms of sensori-motor activity occasioned by them, the 
 whole nerve centre, with dependent nerve system, is allowed 
 to rest in sleep. In such rest there is a double advantage to 
 the brain, the demand upon nerve energy is reduced, and the 
 supply of nourishment is all the while maintained, as the heart 
 continues to pump up a steady course of fresh blood. 
 
 In this connection we come upon the phenomena of dreaming, 
 raising the question as to the extent of mental activity which 
 may go on while a state of slumber is maintained. This is a 
 department of inquiry beset with special difficulty, but it is of 
 obvious importance as bearing on the general problem. If 
 mental phenomena be the product of brain action, or even if 
 they be uniformly connected with activity of brain, rest of the 
 nerve system in sleep should practically terminate mental 
 activity for the time. But if mental phenomena imply the 
 action of a higher nature distinct from the body, though exist- 
 ing in closest union with it, all that will follow as the result 
 of slumber will be a cessation of those forms of mental action 
 concerned with the use of the senses, and the management of 
 bodily movements, — some limitation or modification of such 
 mental exercises as are intimately connected with bodily life, 
 with a possibility of independent mental action in harmony 
 with the mental training of the individual. The present 
 subject of inquiry is, Which view most harmonises with the 
 recognised facts of human life ? 
 
 At the outset, allowance must be made for the excited con- 
 dition of the nerve system in the earlier stage of sleep. It is 
 well known that an excited nervous system is unfavourable 
 to sleep, and that, even after falling asleep, the effects of the 
 prior excitement continue to be manifest. This is clearly re- 
 cognised in the case of children who are much excited in play, 
 and the same rule applies in the case of concentrated study, 
 implying close use of the eyes with all the disadvantages of 
 
xii.] WEARINESS, SLEEP, AND UNCONSCIOUSNESS. 335 
 
 artificial light. The excited nerve system takes some time to 
 quiet, and the early period of sleep is in such circumstances less 
 refreshing. In this period, which may be regarded as an inter- 
 mediate stage between the waking state and that of profound 
 sleep, the remaining excitement of the last hours of the waking 
 state is apt to tell upon experience. This seems to favour a 
 particular line of mental action. Dreaming is prone to take its 
 direction according to the excitement in which the brain is left 
 when the person sinks to sleep. In passing from the waking 
 to the slumbering state there is a continuity of experience, by 
 which the person is so far influenced that the effects may to 
 some extent be apparent to an observer. In classifying the 
 illustrative facts, some distinction is to be made between facts 
 which belong more properly to organism, and others which 
 cannot be explained without reference to mind. To the former 
 class belong restlessness, starting, and a low murmuring sound 
 sometimes heard. Analogous facts are seen in animal life. To 
 another class must be referred articulate utterances, which in- 
 dicate that the person is still intelligently occupied with the 
 engagements which have been physically suspended. Such 
 phenomena as these, while they must have a definite place 
 assigned to them, so clearly belong to a border territory, that 
 it may not unreasonably be argued that they are essentially 
 connected with a lingering excitement of the nerve system, 
 which gradually passes off as sleep deepens. For this reason 
 I prefer to set them aside, and to rely exclusively on evidence 
 of a different order, in which intelligence is legitimately held 
 to be the originating source of recognised activity. The proof 
 required for this purpose is that which indicates that intelli- 
 gence communicates some influence to the slumbering body, 
 rather than that the still excited body throws some disturbing 
 influence upon the mind. 
 
 Some have maintained that our dreams are all connected 
 either with the period when we are sinking to rest, or with the 
 period when we begin to wake ; but any extended observation 
 of others in profound sleep will contradict such a view. Ee- 
 stricting attention to persons in perfect health, and selecting 
 hours when everything is quiet, it will commonly be found 
 that the slumberer is perfectly quiet also ; but at times the 
 
336 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 smile may be seen to come and go, a merry laugh may be 
 heard, or a question addressed to a supposed auditor. It is 
 often urged that such manifestation of thought or feeling 
 implies a disturbed sleep. This cannot be maintained on evi- 
 dence. There is a clearly marked contrast between mental 
 action which involves a disturbing influence, and that which 
 is compatible with undisturbed repose. If all who dream are 
 disturbed, and if the disturbance lasts as long as dreaming 
 continues, there would seem to be some at least who get little 
 rest. But if a distinction be made between the different 
 tokens of mental action during sleep, it will be found that such 
 actions may be separated into two classes, — those which are 
 disturbing and do indeed make sleep less refreshing, and those 
 which interest and please the mind, so as to contribute a 
 soothing influence to the slumbering body. It is one of the 
 familiar observations of ordinary experience during our waking 
 hours, that there are certain forms of mental action which 
 agitate the body, while there are others of a kind pleasing in 
 their influence, and stimulating to healthy action of the body. 
 During the hours of sleep it is apparent that the same contrasts 
 are experienced. Though the proofs of this are not so readily 
 found as during waking hours, while the person is constantly 
 observing external objects and conversing with others, as well 
 as continually observed by others, they are conspicuous in the 
 record of any extended course of observations as to experience 
 during sleep, even excluding the phenomena which belong to 
 the first and closing stages in the period of repose. Some- 
 times there is indubitable evidence that the slumberer is agi- 
 tated by grief or fear ; and again it is obvious that his attention 
 is directed on some pleasing object, or he is reflecting on a 
 theme which occasions gratification. 
 
 Before giving in outline some illustration of the evidence 
 on which reliance is here placed, there is an argument against 
 the opinion that dreaming is customary during sleep, to which 
 reference should be made. It is founded on recollection as an 
 available test of mental activity. The argument is, that if 
 dreaming were so common as must be implied in the possi- 
 bility of mental activity during profound slumber, there would 
 be as ample recollection of our engagements during sleep as 
 
xii.] WEARINESS, SLEEP, AND UNCONSCIOUSNESS. 337 
 
 there is of the occupations of our waking hours. But there is 
 an ohvious and broad contrast between the waking hours and 
 the hours of sleep in respect of facilities for recollection. If a 
 man were to lie all day long on a couch, with his eyes ban- 
 daged, and no one were to enter the room, so that he were left 
 altogether to his own thoughts, this would be the nearest 
 approximation, in a waking state, to the condition of things 
 during sleep. Such a person, spending his day in quietness 
 and separation from external influence, as he is during the 
 night, would find himself at the close of the day with a con- 
 siderably shortened stock of recollections, in comparison with 
 the store which an ordinary day's avocations afford. If, in 
 order to apply to the period of sleep the test which memory 
 affords, we deduct all the aids which come from use of the 
 senses, and from the multitude of fresh associations supplied 
 by the scenes of daily occupation, it will then appear that 
 the argument from the scanty recollections of the morning 
 has lost a considerable degree of its apparent power. But still 
 further, there is no man, with all the advantages of active employ- 
 ment, who will consent to regard the recollections of the evening 
 as an accurate test of the mental activity of the day. If this be 
 so, still less can recollections be made a test of the degree of 
 mental action maintained during sleep. In further estimating 
 the value of the argument from recollection, it is to be observed 
 that the best defined recollections we have of events occurring 
 during our slumbers are those connected with definite scenes, 
 that is, those which imply that we have during sleep attributed 
 to the several senses activity appropriate to the imagined 
 circumstances. If we find it more difficult to recall lines of 
 thought which have been pursued, such perplexity is not at 
 all peculiar to the thinking which we prosecute during our 
 sleep, and may be accounted for simply by the want of definite- 
 ness belonging to the thought itself. Both in waking hours 
 and in the hours of sleep it will be found, as a general rule, 
 that more definiteness belongs to the action of intelligence 
 when connected with the facts which our senses communicate, 
 than with intellectual processes of a more reflective and 
 abstract character. In accordance with this rule of mental 
 life Memory has a less ready and retentive application when 
 
 Y 
 
338 THE RELA TIONS OF MIND AND BRAIN. [chap. 
 
 the mind is occupied with less denned subjects of contempla- 
 tion. With these preliminary remarks indicating the condi- 
 tions under which we can reasonably estimate the testimony 
 of our recollections as to mental activity during sleep, we are 
 prepared for a summary of the evidence itself. 
 
 1. While, the senses are sealed in slumber, the imagination is 
 often occupied with a representation of scenes and occurrences 
 such as are recognised by the senses. — Under this statement are 
 included the examples of the class of dreams most familiar to us. 
 The sleeper, when liberated from the demands of daily work, 
 and withdrawn from the relaxations of the social gathering, 
 goes back at times upon the scenes of the past, sees again the 
 familiar places where he has often spent happy hours, and 
 enjoys communion as of old with those who were wont to be 
 associated with him. In support of the conclusion that such 
 use of the imagination is not to be accounted for by the effects 
 which the circumstances of the preceding day have had upon 
 the brain, such dreams involve restoration of past relations, in 
 strict accordance with the state of matters at the distant period. 
 Thus the agents depicted by the imagination are exactly as 
 they were long years before. Those who are now in distant 
 lands are present as they were then; those who are sadly 
 weakened now are seen moving about in full vigour ; those who 
 have been removed by death are present taking their familiar 
 part, and wearing their familiar looks. Testimony to such facts 
 is so abundant, that there can hardly be a single individual 
 who has not oftentimes had to report such experience. Some 
 argue that the inconsistency of such imaginings with the facts 
 of the present time shows that the mind is at least somewhat 
 confused, and does not act with the same vigour as in its 
 waking hours. But such an argument would be as powerful 
 against the rational consistency of imaginative exercise during 
 our waking hours, and it does not appear that any one considers 
 himself confused in mind, or lacking in his wonted intellectual 
 vigour, when he allows imagination to roam with delight over 
 some part of the road he has travelled, or to linger in the midst 
 of some of those social gatherings in distant days which seemed 
 to have a special brightness over them. The inconsistency of 
 the facts represented with the actual circumstances of the 
 
xii.] WEARINESS, SLEEP, AND UNCONSCIOUSNESS. 339 
 
 sleeper at the time, shows how independent of present experi- 
 ence and position the exercise of the imagination. is ; the con- 
 sistency of the dream in itself shows how rationally the sleeper 
 employs his recollections. That dreams are always thus self- 
 consistent, no one will say, for they are often enough grotesque 
 in combinations, and not infrequently they involve the per- 
 formance of impossible feats. Alongside this statement must, 
 however, be placed the other, that even our " day dreams " are 
 not invariably so rational as completely to escape a similar 
 charge. We are not always consistent in our use of imagina- 
 tion, even when we are wide awake. If the fancies of our 
 sleeping hours are more commonly grotesque and inconsistent, 
 they are conceived under entirely different mental conditions. 
 While the mind is for the time deprived of the aids of the 
 special senses, it is liberated from their restraints, and no 
 longer finds it needful to have regard to surrounding objects, 
 or to the restrictions of time and space. Having a clear advan- 
 tage as to facility of action, the agent is capable in fancy of 
 compressing into a few minutes, occurrences which would take 
 hours to accomplish under the ordinary conditions. But, while 
 thus appearing to accomplish what is impossible, there is clear 
 evidence of accurate intellectual exercise. This becomes so 
 marked in many of our dreams that a lengthened conversation 
 is carried through, all the parts of which are maintained by the 
 sleeper himself. What remains in the memory after awaking 
 is a consistent scene, as completely harmonious in all its parts 
 as any actual interview of friends. 
 
 There is more difficulty in attempting to account for the 
 incongruous combinations which occur at times in course of 
 our dreams. Many of them may be explained by a restless 
 physical condition, such as may be implied in the excited state 
 of the brain before sinking to rest, the feverishness induced by 
 cold, or endurance of pain. In illustration of the influence of 
 suffering, Dr. Eeid records the following experience: 1 — "I had 
 got my head blistered for a fall. A plaster, which was put 
 upon it after the blister, pained me excessively for a whole 
 night. In the morning, I slept a little, and dreamed very dis- 
 tinctly that I had fallen into the hands of a party of Indians, 
 1 Beid's Works, Hamilton's ed., p. 34, 
 
340 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 and was scalped." Another class of dreams may be referred 
 to disturbing causes around, such as unusual noises, strong 
 odours, or considerable increase in the amount of light. The 
 mind proceeds to make some account of its varying experience. 
 It is not improbable that some additional incongruity may 
 arise from the mixed character of our recollections, blending 
 together occurrences which were considerably separated in 
 course of the night. We can have no adequate test of the sug- 
 gesting or stimulating occasion for many of the fancies which 
 arise within the mind, but many of them must be attributed 
 to our physical condition and our surroundings. After all allow- 
 ance has been made, however, for the seemingly incongruous, 
 there still waits for explanation a large amount of mental 
 activity, giving evidence of a high degree of intellectual vigour. 
 2. There, is power of persistent determination and intelligent 
 appreciation of previously formed purpose, influencing the sleeper 
 from the beginning to the close of his slumbers. — A determination 
 to awake at a given hour can be exactly fulfilled. 1 There are 
 some who feel that any such purpose has a disturbing effect 
 upon their slumbers, specially if important consequences hang 
 upon strict adherence to a determination to awake at an early 
 hour. This is apt to prove true, if one has to transact urgent 
 business, or keep an engagement of special importance. But 
 the needless awaking at such hours as two o'clock in the 
 morning, and again at four, of which complaints are made by 
 those so situated, only illustrates how thoroughly the person 
 continues to concern himself during sleep with the pressing in- 
 terest of the time. Cerebral disturbance presents no adequate 
 explanation. But a still better illustration is afforded, because 
 more free from casual excitement, when one's determination 
 concerns waking for the purpose of resuming ordinary engage- 
 ments. Some deduction must here be made on account of the 
 physical habit which becomes established by keeping to a 
 regular hour of waking, as illustrated by the tendency to awake, 
 when the intention of the sleeper had been to rest somewhat 
 longer than usual. Even with this deduction, however, there 
 remains a large amount of evidence confirmatory of the conclu- 
 sion that the intelligent nature continues active while sound 
 1 field's Works, Hamilton's eel., p. 34. 
 
xii.] WEARINESS, SLEEP, AND UNCONSCIOUSNESS. 341 
 
 sleep is maintained. I have repeatedly had tests of such 
 action, by waking too early, taking note of the remaining time 
 to he allowed to sleep, resolving to give no heed to the single 
 stroke of the time-piece at the half hour, but to rise promptly 
 when a succession of strokes was heard. This plan has been 
 repeatedly carried out with such exactness in my own experi- 
 ence, as to afford clear proof of persistent determination during 
 quiet sleep, a proof which is strengthened by the eagerness 
 with which one starts up lest the inopportune waking had 
 defeated the intention. 
 
 From observations as to the sleep of others I shall give only 
 a single example. When on a visit in midsummer to a friend 
 in a quiet rural district in the south of Scotland, I proposed to 
 get up at four o'clock in the morning, to have a few hours' 
 fishing before breakfast. One of the boys of the family hearing 
 the proposal, made an earnest request that he might be allowed 
 to go also. His parents gave permission, and a promise was 
 made that he should be wakened at the proper time. When 
 next morning at the time appointed I got to his bed-room, he 
 was profoundly sleeping, and a door between his room and that 
 of his parents was a little open. It thus became an object to 
 wake him without disturbing them. I got down on my knees 
 that I might call his name closely to his ear. This was done 
 repeatedly without producing the slightest effect. Next I took 
 his hand and worked his arm up and down, a process which 
 resulted only in a slight murmur. More rigorous measures 
 being required, I began to turn him from side to side. This 
 when repeated induced him to say, "What's wrong?" The 
 movement being still continued, he began to stir himself, and 
 suddenly exclaimed, " Oh, I see what it all means !" and im- 
 mediately a look of recognition settled the matter between us. 
 It was not needful that I should utter a word of explanation, 
 for his appreciation of the circumstances was instantaneous. 
 
 A most striking example of strong determination maintained 
 through sleep is that recorded by Dr. Eeid, Professor of Moral 
 Philosophy in Glasgow. " About the age of fourteen," he tells 
 us, he had always frightful dreams, as if he were falling over a 
 precipice. He gives us the following interesting account of his 
 effort to gain the mastery over these dreams : — " I thought it 
 
342 THE RELA TIONS OF MIND AND BRAIN. [chap; 
 
 was worth trying whether it was possible to recollect that it 
 was all a dream, and that I was in no real danger. I often 
 went to sleep with my mind as thoroughly impressed as I could 
 with this thought, that I never in my lifetime was in any real 
 danger, and that every fright I had was a dream. After many 
 fruitless endeavours to recollect this when the danger appeared, 
 I effected it at last, and have often, when I was sliding over a 
 precipice into the abyss, recollected that it was all a dream, 
 and boldly jumped down. The effect of this commonly was 
 that I immediately awoke ; but I awoke calm and intrepid, 
 which I thought a great acquisition. After this my dreams 
 were never very uneasy, and in a short time I dreamed not at 
 all." 1 Even if we suppose he invariably awoke, the laws of 
 cerebral action are insufficient to account for the facts. 
 
 3. There, are many examples of concentrated intellectual action 
 during sleep. — Any mental exercise prosecuted during slumber 
 will be in accordance with the intellectual habits and develop- 
 ment of the individual. In the dreams of a child there are 
 not likely to be examples of a kind which can come under this 
 division of evidence ; nor can we hope to find many illustra- 
 tions of the kind in the case of those who give themselves 
 little to close intellectual effort during their waking hours. 2 
 There must be intellectual interest and habitual exercise in 
 reflective processes, in order to give any reasonable expecta- 
 tion that intellectual activity may be continued in a given 
 direction during the hours of slumber. There must also be 
 some distinction drawn between the experience of those noted 
 for a high degree of sensibility, bodily and mental, such as 
 Charles Lamb and De Quincey, whose mental activity largely 
 involves sensory impressions and their effects upon the imagi- 
 nation, and the experience of those devoted to more abstract 
 study, involving severance from external impressions. The two 
 classes of thinkers are distinguished by very marked differ- 
 ences, and the testimony from them will naturally differ to a 
 considerable extent. The dreams of such a man as De Quincey 
 naturally assume a pictorial or dramatic form, and might come 
 
 1 field's Works, Hamilton's ed., p. 34 ; or Dugald Stewart's Works, vol x. 
 p. 321. 
 
 2 Dugald Stewart's Works, vol. ii. p. 291. Elements, chap. v. sect. 5. 
 
xii.] WEARINESS, SLEEP, AND UNCONSCIOUSNESS. 343 
 
 under the first division of evidence, were it not that the pre- 
 sence of finer sensibilities and phases of discrimination give 
 predominance to the intellectual nature. In such a case as 
 his we must make allowance for what he notices as true of 
 Lamb, when he says : " The sensibility of his organisation was 
 so exquisite that effects which travel by separate stages with 
 most other men, in him fled along the nerves with the velocity 
 of light." We must also have regard to " the pensiveness 
 chequered by gleams of the fanciful, and the humour which 
 is touched with cross lights of pathos." l We must make full 
 account of what De Quincey describes as " the interaction be- 
 tween the author as a human agency, and his theme as an intel- 
 lectual re-agency." 2 And we must add to these things the 
 lonely pondering, characteristic of him, and often apt to be 
 prolonged, as when Wordsworth writes thus of him: — "Mr. 
 De Quincey has taken a fit of solitude ; I have scarcely seen 
 him since Mr. Wilson left us." We can well understand what 
 there was to De Quincey in the departure of the stalwart 
 Moral Philosopher of Edinburgh University, whose sponta- 
 neous, ever sparkling mirth and lofty sentiment spread sun- 
 shine around him on all sides. But this tendency to seek 
 solitude gives an additional characteristic connected with his 
 natural pensiveness. We must then expect somewhat different 
 results in the case of a thinker such as De Quincey, physically 
 predisposed for dreaming, with the natural tendency greatly 
 intensified by use of opium, leading to his " Oriental Dreams," 
 and such distinctively abstract thinkers as Locke, Thomas Eeid, 
 Dugald Stewart, and Sir William Hamilton. De Quincey had 
 a dream-land always open during his waking hours, and in har- 
 mony with this we have large testimony as to his experience 
 of mental activity during slumber. 8 If we take the abstract 
 thinkers, we have testimony of a different kind. Locke in the 
 midst of his polemio against Des Cartes, represents our dreams 
 as " extravagant and incoherent for the most part," and quotes 
 the case of a young man of good education, twenty-five years 
 
 1 Leaders in Literature — Charles Lamb. De Quinoey's Collected Works, 
 vol. ix. p. 110. 
 
 2 lb. p. 112. 
 
 3 See Thomas De Quincey, &i's Life and Writings, by H. A. Page. 
 
344 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 of age, who said that he had never dreamed in his life until 
 he had a fever, from which he was at the time recovering. 
 Dubious as to the frequency of dreaming, Locke says : " Wake 
 a man out of a sound sleep, and ask him what he was at that 
 moment thinking of." 1 This very test Sir William Hamilton 
 applied in his own experience, and the results are recorded in 
 the following words : — " I have always observed that when 
 suddenly awakened during sleep (and to ascertain the fact 
 I have caused myself to be roused at different seasons of the 
 night), I have always been able to observe that I was in the 
 middle of a dream. The recollection of this dream was not 
 always equally vivid. On some occasions I was able to trace 
 it back until the train was gradually lost at a remote dis- 
 tance ; on others, I was hardly aware of more than one or two 
 of the latter links of the chain, and sometimes was scarcely 
 certain of more than the fact that I was not awakened from 
 an unconscious state." 2 On the other hand, taking recollection 
 as the test, without resorting to the plan of being wakened at 
 different hours of the night, Dr. Thomas Eeid could say, " For 
 at least forty years I dreamed none, to the best of my remem- 
 brance." 3 But it must be noticed, in estimating the two 
 statements, that Hamilton's is the result of deliberate ex- 
 periment for purposes of observation, while, on the other 
 hand, -it needs to be admitted that both Locke and Keid had 
 their reasonings somewhat coloured by polemic influences. 
 
 I have gathered a number of examples of mental activity 
 during sleep, which give evidence of concentrated intellectual 
 effort. These include such varieties as the following : — a con- 
 tinuous course of reasoning, reproduced after waking ; listening 
 to a lengthened discourse, which must have been composed by 
 the sleeper, and a long outline of which was afterwards given ; 
 reflecting on a problem, and experiencing such satisfaction with 
 the result, that the person awoke, got up at once, and wrote 
 notes of the positions. From the many valuable cases recorded 
 
 1 Essay ore the Human Understanding, ii. i. see. 19. 
 
 2 Metaphysics, vol. i. p. 322. 
 
 3 Works of Thomas Reid, Eamilton'a edition, p. 34. The letter from which 
 this is an extract ia one of great interest, arid is given in Dugald Stewart's 
 Life of Reid, included in Stewart's Collected Works, vol. x. p. 320. 
 
xii.] WEARINESS, SLEEP, AND UNCONSCIOUSNESS. 345 
 
 by Dr. Abercrombie, I take an exceedingly striking example. 
 " The following anecdote has been preserved in a family of rank 
 in Scotland, the descendants of a distinguished lawyer of the 
 last age. This eminent person had been consulted respecting a 
 case of great importance and much difficulty, and he had been 
 studying with intense anxiety and attention. After several 
 days had been occupied in this manner, he was observed by 
 his wife to rise from his bed in the night, and go to a writing- 
 desk which stood in the bed-room. He then sat down and 
 wrote a long paper, which he put carefully by in the desk, and 
 returned to bed. The following morning he told his wife that 
 he had had a most interesting dream ; that he had dreamt of 
 delivering a clear and luminous opinion respecting a case 
 which had exceedingly perplexed him ; and that he would 
 give anything to recover the train of thought which had 
 passed before him in his dream. She then directed him to 
 the writing-desk, where he found the opinion clearly and fully 
 written out, and which was afterwards found to be perfectly 
 correct." 1 Such cases cannot be explained by "unconscious 
 cerebration." Cerebral activity there is, of course, but it is 
 shown besides that concentrated intellectual activity is com- 
 patible with profound sleep. A near relative of my own, 
 through long years a sufferer, and for the most part confined 
 to bed, greatly lamented the loss sustained by absence from 
 church on the Sabbath-days. She did the utmost that could 
 be done to make up for that loss by very constant and careful 
 study of the Bible, and by getting the members of her family to 
 give the fullest outline they could of the expository discourse 
 usually given at the forenoon service, and of the sermon de- 
 livered in the afternoon. The main current of her thought was 
 determined by these two things, personal reflection on Scrip- 
 tural statements, and such aids as were afforded in " the re- 
 ported form of speech," by her own young people doing their 
 best at reproduction, without violation of "copyright." By 
 means of the latter aid her associations with the church ser- 
 vices were constantly maintained. On one occasion she told 
 us that she had dreamed of being at church, and had heard 
 there an admirable sermon. She stated the text, became her- 
 1 Abercrombie's Intellectual Powers, 12th ed., p. 234. 
 
346 THE RELA TIONS OF MIND AND BRAIN. [chap. 
 
 self for this occasion the " reporter," and at great length gave 
 us not only the main divisions of the discourse, but the prin- 
 cipal lines of exposition and illustration adopted under each. 
 To our surprise we listened to an extended account of a ser- 
 mon none of us had either heard before, or reported to her, 
 which she had not read, and which, after due consideration 
 given, we were forced to conclude was an example of her own 
 production, presented to a restricted audience, without violation 
 of the ecclesiastical law against " female preachers." 
 
 A summary of the conclusions which may fairly be deduced 
 from the large body of evidence at command, has been admir- 
 ably presented by Dr. Noah Porter, President of Yale College, 
 Connecticut, United States. He says : " The exercise of judg- 
 ment in respect to the higher relations of thought varies very 
 greatly in the energy of its action and the perfection of its 
 results. There are many cases in dreams in which single steps, 
 or parts of a series of steps in reasoning, are taken surely and 
 correctly, while these processes are entirely disconnected with 
 what went before and followed after, as if the rational powers 
 had resumed for a single instant their full energy of function. 
 In other cases the reasoning may be correct and the data may 
 be false, and yet the falseness of the data may not be per- 
 ceived. In still other cases, the data "may be correctly dis- 
 cerned, and the conclusions correctly derived, so that both 
 premises and reasoning combine to a valid and true conclusion. 
 Even the more difficult feats of the invention and construction 
 of the materials of an argument have been successfully per- 
 formed in dreams. The creations of poetry, even to the selec- 
 tion of rhythmical words, the composition of sermons and 
 addresses, have been often effected. Difficult problems iu 
 mathematics have been solved and remembered ; new and in- 
 genious theories have been devised, happy expedients of deli- 
 verance from practical difficulties have presented themselves, 
 and brought relief from serious embarrassments." After giving 
 examples in confirmation of these statements, Dr. Porter pro- 
 ceeds to say : " In all examples of this kind, the successful 
 exercise of reasoning and invention is always in that form of 
 activity to which the person is familiarly accustomed, and it is 
 not always easy to distinguish between the suggestion to the 
 
XII.] WEARINESS, SLEEP, AND UNCONSCIOUSNESS. 347 
 
 memory of what had been previously achieved by a man when 
 awake, and an original act of the mind upon the data brought 
 before him for the.first time in his dreams." 1 
 
 If now a general survey be made of the evidence adduced 
 as to experience in dreaming, two distinct conclusions seem 
 warranted. First, that a considerable portion of the pheno- 
 mena included under the general designation of dreaming may 
 be accounted for by the excitement of the bodily state before 
 going to sleep, or impressions made on the sensory system 
 during sleep. Second, that a large body of the evidence accumu- 
 lated by independent observers implies fixed determination and 
 concentrated intellectual effort during sleep. With ground for 
 a twofold classification of the facts adduced concerning dream- 
 ing, we are led to the inference that intellectual activity is 
 compatible with that rest to the muscular system, the sensory 
 and motor nerves, and the nerve centre, which is obtained 
 in sleep. And towards an explanation of this intellectual 
 activity we perceive that the evidence of such action is more 
 abundant in the case of those who have developed their powers 
 of reflection by voluntarily acquired habits of concentra- 
 tion. There is thus shown to be a continuity of intellectual 
 work during sleep — a progression of thought from the waking 
 hours into the silent hours of the night — which is more con- 
 centrated and valuable according to the mind's interest in the 
 subject of study. Further, it is shown that the mind during 
 sleep manifests all those characteristics known to belong to the 
 individual in his ordinary avocations. The poet is in sleep 
 poetical in his intellectual effort, the musician is musical, the 
 mathematician is mathematical, the philosopher is philoso- 
 phical. There is assuredly no warrant for maintaining that 
 intellectual work can be uniformly prosecuted exactly as in 
 waking hours ; but if allowance be made for two things — the 
 termination of such conscious relation to things external as is 
 implied in the activity of the senses throughout the waking 
 state, and intensity of intellectual interest in some employ- 
 ment not essentially dependent on the use of the senses, — it is 
 
 1 The Human Intellect, by Dr. Noah Porter, President of Yale College, 
 p. 336. Ample confirmation of Dr. Porter's summary will be found in 
 Dr. Abererombie's Intellectual Powers, ut sup. pp. 210-237. 
 
348 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 proved that mental activity of a high order is compatible with 
 physical repose in sleep. 
 
 From the phenomena attendant on the state of slumber, we 
 may pass to deeper phases of unconsciousness at times con- 
 nected with other states of body. We are accustomed to speak 
 of our experience in falling asleep, as sinking into unconscious- 
 ness. But a restricted meaning is attached to the word " un- 
 consciousness " in this case, and a much wider significance is 
 assigned to it in other cases. If a person sitting quietly with 
 book in hand of an evening in the family circle drop asleep 
 for a few minutes, or if a member of Parliament be seen nap- 
 ping during a debate, or one of the audience fall asleep in 
 church, we say he is unconscious of all that is going on around 
 him. And yet this is so far from being strictly correct that 
 any unusual movement in the room will cause the first to wake 
 up, the division-bell will rouse the second to inquire what the 
 vote is, and a sudden pause in the service will awake the third. 
 There is thus unconsciousness of surrounding occurrences so 
 long as they imply a continuance of the conditions under 
 which sleep began ; but there is a consciousness of any unex- 
 pected change, which is often sufficient to terminate sleep, 
 by directing attention upon the occasion of disturbance. But 
 that is in a deeper sense an unconscious state into which one 
 passes who faints in stifling atmosphere, or under sudden fright, 
 or is subject to epileptic fits, or who is caught in some cata- 
 strophe, receiving a violent stroke on the head, or being sorely 
 crushed in machinery, or is placed under dominion of chloro- 
 form preparatory to a surgical operation. Any one of these 
 cases illustrates a completely unconscious state, which requires 
 consideration in connection with the relations of mind and 
 brain. The person who lies in this condition gives no evidence 
 of mental activity, though the action of the vital organs is con- 
 tinued. Communication between the patient and the friends 
 around him is completely broken. No word tells upon the 
 ear, — no sight is possible to the eye, — puncturing of the skin 
 occasions no pain,— tickling of the soles of the feet produces 
 no reaction. In such cases, there are different degrees of 
 alteration in the nerve system, involving a shorter or longer 
 continuance in the condition of unconsciousness. At one time 
 
xn.] WEARINESS, SLEEP, AND UNCONSCIOUSNESS. 349 
 
 unconsciousness may not last for more than a few minutes, at 
 another it may be for the greater part of an hour, and at 
 another it may continue for days. An explanation of this con- 
 dition in all the aspects in which it affects human life may 
 always continue an impossibility. When the aids of conscious- 
 ness and memory are lost, the sufferer is deprived of the 
 means of contributing personal testimony, and the observation 
 of others extends only a little way. We are, therefore, practi- 
 cally restricted to a study of the conditions which lead to the 
 loss of consciousness. When we turn to these, it appears that 
 this physical condition may be induced by mental as well as 
 physical causes. Beyond doubt the essential feature in the 
 condition is suppression of the ordinary functions of brain. 
 And that may be induced either by direct injury to the 
 organism itself, or by undue disturbance of it through agitation 
 of mind, involving interference with the functional activity of 
 the brain. The disturbance may come either from within, or 
 from without ; but temporary injury to the brain is the conse- 
 quence, and the twofold source of disturbance affords additional 
 illustration of the correlation of body and mind. 
 
 1. The state of unconsciousness may le induced by physical 
 injury involving interruption of brain activity. — While uncon- 
 sciousness may be traced to physical causes, it is not every 
 kind of physical injury which is attended by results so serious. 
 A very large amount of pain and even bodily laceration can 
 be experienced without any threatening of loss of conscious- 
 ness. This may be illustrated by reference to fainting. It 
 often happens that a much more serious amount of suffering 
 is endured by the man who shows no tendency to faint, than 
 by the person who has sunk into the condition more alarming 
 to onlookers. In accordance with this contrast, the person of 
 "nervous temperament," that is, the person low in muscular 
 energy, and sensitive to every influence which acts upon nerve 
 excitability, is prone to faint under experience of discomfort 
 which would not much disturb a person in a high degree of 
 physical strength. But, while here looking at purely physical 
 conditions, we cannot altogether exclude reference to the mind. 
 The person who is in a nervously excitable state greatly aggra- 
 vates the effect of outward influences by the action of the mind 
 
350 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 in attending to them. In so far as the influences inducing 
 faintness are purely physical, the tendency will be quickened 
 by increased measure of deleterious influence, such as exhaus- 
 tion of the atmosphere in a crowded apartment. In so far as 
 the influences operating are mental, the result depends upon 
 the extent to which the person directs attention to the cause 
 of uneasiness, or keeps the attention turned on other conside- 
 rations, so averting the mind from physical impressions. The 
 result is not calculable as in the former case, but will be ac- 
 cording to personal determination, that is, the action of the 
 individual mind. It is when the body is weakest and the 
 nerve system most excitable that the action of the mind is 
 most prone to aggravate the risks of fainting. Here it should 
 be observed that the accession of mental influence is more 
 especially characteristic of liability to the more transitory form 
 of unconsciousness. As this is apparent, it points to the con- 
 sideration, that low vitality involving nerve excitability in 
 absence of normal power of control, is in itself an approxima- 
 tion to the unconscious state. 
 
 When we pass to a more aggravated form of unconsciousness, 
 such as is seen in an epileptic fit, there is more thoroughly 
 established brain disorder, and less influence of mind deter- 
 mining the physical condition under the paroxysm. The 
 patient may, indeed, increase his personal uneasiness by ap- 
 prehension of the approaching attack, and may even accelerate 
 its advance ; but the state of paroxysm, which interferes with 
 normal sensory and motor action, is purely the result of brain 
 disorder, and not at all the effect of mental action. If next 
 we advance to the unconsciousness which is not consequent 
 on a diseased condition of braiu, but upon violence inflicted 
 by a blow or a fall, there is nothing of mental influence con- 
 tributing to the result, though an effectual interruption is 
 occasioned to mental activity, as well as to the ordinary action 
 of the sensori-motor system. The man is for the time in- 
 capable of physical activity, and equally incapable of mental. 
 
 2. A state, of transitory unconsciousness may be induced by 
 mental action when the physical condition is healthy.— Sudden 
 tidings, either of a peculiarly joyous or of a particularly sorrow- 
 ful kind, often give the physical nature an unexpected shock. 
 
xii.] WEARINESS, SLEEP, AND UNCONSCIOUSNESS. 351 
 
 Such a shock is often sufficient to throw the recipient of the 
 tidings into a faint. The prostration so witnessed is not the 
 result of a previously disordered condition, nor is it the direct 
 effect of the sensory impression when the words are spoken ; it 
 is the consequence of the interpretation put upon the words, 
 and the anticipation of results seen to be involved in the 
 tidings communicated. The effect is the same as if a blow had 
 been received on the head, and so we speak of any calamity 
 as " a sad blow " to the person concerned. There has been no 
 use made of physical force, there has been nothing more than 
 the utterance of a single sentence, but the hearer of it feels as 
 if a blow had been delivered, and as if a sudden quiver had 
 passed over the whole body. 
 
 This same result is apt to occur when, instead of a sudden 
 message being received, there has been long continuance of 
 excitement and anxiety. This is well illustrated by an inci- 
 dent related by Dr. Santagata, which occurred early in the 
 career of Mezzofanti, when he stood a public examination in 
 philosophy. As a student at the University of Bologna, and 
 a candidate for the degree in philosophy, Mezzofanti was, 
 according to custom, called upon publicly to defend a series of 
 philosophic propositions against the objections stated by the 
 examiners. " For a time the boy's success was most marked. 
 Each new objection, among the many subtle ones which were 
 proposed, only afforded him a fresh opportunity of exhibiting 
 the acuteness of his intellect, and the ease, fluency, and elegance 
 of his Latinity; and the admiring murmurs of assent, and 
 other unequivocal tokens of applause which it elicited from 
 the audience, of which I myself was one, seemed to promise a 
 triumphant conclusion of the exercise. But all at once the 
 young candidate was observed to grow pale, to become sud- 
 denly silent, and at length to fall back upon his seat, and 
 almost faint away. The auditors were deeply grieved at this 
 untoward interruption of a performance hitherto so successful ; 
 but they were soon relieved to see him, as if by one powerful 
 effort, shake off his emotion, recover his self-possession, and 
 resume his answering with even greater acuteness and solidity 
 than before. He was greeted with the loud and repeated 
 plaudits of the crowded assembly." 1 Any one who has gone 
 
 1 Marshall's Life of Mezzofanti, p. 139. 
 
352 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 through an ordeal of this kind, and has experienced the nervous 
 excitement which it entails, knows that there is both a physical 
 and a mental element to be taken into account. There is a 
 gradual abatement of physical strength experienced when the 
 effort has been protracted. But quite distinct from this, and not 
 resulting from ordinary functional activity of the cerebrum, there 
 is apprehension as to the result of the discussion, doubt as to 
 whether the questioning is being fully understood, and a fear lest 
 it should prove impossible to keep up the standard attained, and 
 to fulfil the expectations of friends. All these apprehensions 
 cause a physical agitation, which, if it be allowed to grow, will 
 soon involve the entire mental exercise in confusion, and may 
 at length throw the body into a state of unconsciousness. 
 Such an example as this serves a double purpose, illustrating 
 how a purely mental anxiety may awaken physical agitation, 
 and how naturally it follows that such physical excitement 
 tends to destroy control of the nerve system, and at the same 
 time to distract and obstruct intellectual action. In view of such 
 occurrences, there can be no warrantable perplexity in the fact 
 that the physical prostration of the unconscious state not only 
 puts a check on consciousness of sensory impression and of 
 motor activity, but also on higher intellectual exercises, all of 
 which must be impossible under the conditions. The facts 
 connected with an unconscious state are so far from being 
 adverse to the theory of the distinct nature of mind, that, if on 
 one side they illustrate the power of the body in restraining 
 mental action, they also illustrate, on the other, the power of 
 mental activity to throw over on the body a degree of agitation 
 which it is not able to bear. 
 
 Before passing from this division of the subject, there are 
 certain phenomena of an abnormal type, including somnam- 
 bulism or sleep-walking, the state of trance, and the mesmeric 
 sleep, to which a brief reference seems desirable. There is a 
 sufficient body of evidence as to such abnormal phenomena to 
 call for an explicit reference, and to afford some test of our 
 arguments as to the relations of mind and brain. 
 
 In somnambulism or sleep-walking, the mind is occupied as 
 in dreaming, but the dreamer gets out of bed and puts into 
 execution the purposes formed in his dream, exactly as he 
 
xii.] WEARINESS, SLEEP, AND UNCONSCIOUSNESS. 353 
 
 would do were he awake and in his ordinary attire. As a rule, 
 the eyes of the somnambulist are wide open, but at times the 
 person appears with closed eyes, yet apparently distinguishing 
 objects around. Dr. Dyce of Aberdeen reports a case, the 
 account of which is repeated by Dr. Abercrombie, of a servant- 
 girl who was subject to fits of somnolency during the day, 
 under which she " became capable of following her usual em- 
 ployment." " She repeatedly dressed herself and the children 
 of the family, her eyes remaining shut the whole time." 1 This 
 case differs in some respects from ordinary somnambulism. In 
 all cases which have come under my own observation, the eyes 
 have been wide open, but never directed upon any of the 
 objects in the room, and never upon myself, even when a con- 
 versation was maintained with the sleeper. The pupils have 
 been always more dilated than in the natural state, lacking such 
 expression as appears when observation is concentrated on 
 an object, and have uniformly had a remote look, as if the 
 person were seeing beyond the walls of the room. There can 
 be no doubt that in this condition the person experiences a 
 considerable degree of cerebral excitement, unfavourable to 
 natural repose. Children of nervous temperament are often 
 liable to sleep-walking, if allowed to engage in very exciting 
 games just before the ordinary hour for retiring to rest. If 
 they are to have the full benefit of their sleep, and to be saved 
 the consequences of establishing a habit of cerebral excitement 
 during their slumbers, exciting games must be ended at least 
 two hours before the usual time for retiring, a rule which would 
 be well applied to all concentrated brain effort, if the first 
 hours of sleep are to be thoroughly refreshing. Light reading 
 before going to bed is as good a prescription as a light supper. 
 There are mental conditions favourable to sleep as well as 
 physical. In somnambulism there is, as I have said, actual 
 performance of what is contemplated during the dreaming state. 
 Is not this, then, the difference between dreaming and som- 
 nambulism, that the dreamer appears in some measure to re- 
 cognise that he is sleeping, whereas the somnambulist does not? 
 Accordingly it is a bad expedient to awake the somnambulist 
 when he is moving about. Such waking gives a shock to the 
 1 Abererombie's Intellectual Powers, 12th ed., p. 244. 
 Z 
 
354 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 whole body ; it is a sudden startling of the person by the dis- 
 covery that he is engaged in an unnatural and dangerous exer- 
 cise, and this discovery involves a degree of agitation which is 
 altogether escaped if he is not wakened. Nor is there any 
 need for wakening in order to direct his movements, for in the 
 somnambulistic state he is capable of maintaining two per- 
 fectly distinct courses of thought, and gradually mingling 
 them, as we do mix up utterly inconsistent facts in our dreams. 
 Thus a child in the somnambulistic state will play over again 
 the game he was engaged with before retiring to rest, — will rush 
 about the room as if pursued by his companion, — will avoid 
 the table and chairs as he runs, doing everything exactly as if 
 awake. If, while he is in full career, one of his parents address 
 him by name in the ordinary tone, telling him that he should 
 go to bed now, he will do it at once, and commonly will do so 
 without going through the feint of putting off his clothes. The 
 two mental exercises are quite readily intertwined, and it 
 becomes obvious that the mind has taken some account of the 
 fact of sleep. So any one bent on an excursion, and found 
 unlocking the street door, may be easily stopped, either by the 
 person addressing him falling in with his intentions, and 
 telling him to take a particular direction, or distinctly advising 
 him to go to bed meanwhile. I have repeatedly advised the 
 somnambulist to go back to bed, and, after a little appearance 
 of perplexity, he did so, as if recognising that he was asleep, 
 though occupied otherwise. It is clearly shown by a large 
 number of the recorded cases, that in this state the mind is 
 capable of following two distinct trains of thought, and so com- 
 bining them as to work them into harmony for the regulation of 
 the conduct. In this way the somnambulist appears to himself 
 to gain two ends at once, or his purpose seems to him to be 
 accomplished, while in reality the purpose of some adviser 
 who has become aware of his state is fulfilled. A further fact 
 deserves notice, as throwing light on the memory test applied 
 to settle the problem as to the extent to which dreaming is 
 characteristic of our sleeping state. The somnambulist comes 
 out of his sleep with no recollection of what he has done in 
 walking hither and thither, and often without any remembrance 
 of the mental exercise through which he has passed. A very 
 
xil.] WEARINESS, SLEEP, AND UNCONSCIOUSNESS. 355 
 
 o 
 
 good example of the somnambulist's conduct is given by Dr. 
 Abercrombie. He says : — " I have received from an eminent 
 medical gentleman in London a case presenting some inter- 
 esting features, which occurred in the person of a young man 
 residing in his house as a pupil. This young gentleman was a 
 zealous botanist, and had lately received the highest botanical 
 prize from a public institution. One night, about an hour 
 after he had gone to bed, after his return from a long botanical 
 excursion, his master, who was sitting in a room below, heard 
 a person coming down stairs with a heavy measured step, and, 
 on going into the passage, found his pupil, with nothing on 
 him but his hat and his shirt, his tin case swung across his 
 shoulders, and a large stick in his hand. ' His eyes,' says my 
 informer, 'were more open than natural, but I observed he 
 never directed them to me, or to the candle which I held. 
 While I was contemplating the best method of getting him to 
 bed again, he commenced the following dialogue: "Are you 
 going to Greenwich, sir?" "Yes, sir." "Going by water, 
 sir?" "Yes, sir." "May I go with you, sir?" "Yes, 
 sir; but I am going directly, therefore please to follow me." 
 Upon this I walked up to his room, and he followed me with- 
 out the least error in stepping up the stairs. At the side of 
 his bed I begged he would get into the boat, as I must be off 
 immediately. I then removed the tin case from his shoulders, 
 his hat dropped off, and he got into bed, observing he knew my 
 face very well, — he had often seen me at the river's side.' A 
 long conversation then ensued between him and the supposed 
 boatman, in which he understood all that was said to him, and 
 answered quite correctly respecting botanical excursions to 
 Greenwich made by the professor of botany and his pupils ; and 
 named a rare plant he had lately found, of which the superin- 
 tendent of the botanic garden had seen only one specimen in his 
 life, and the professor only two. After some further conversation 
 he was asked whether he knew who had gained the highest 
 botanical prize ; when he named a gentleman, but did not name 
 himself. ' Indeed ! ' was the reply, ' did he gain the highest prize ? ' 
 To this he made no answer. He was then asked, ' Do you know 
 
 Mr. V naming himself; after much hesitation, he replied, 
 
 ' If I must confess it, my name is .' This conversation 
 
356 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 lasted three quarters of an hour, during which time he never 
 made an irrelevant answer, and never hesitated, except about 
 the prize and his own name. He then lay down in bed, saying 
 he felt tired, and would lie upon the grass till the professor 
 came. But he soon sat up again, and held a long conversation 
 with another gentleman who then came into the room, when 
 he again understood everything that was said to him, and an- 
 swered readily and correctly, sometimes uttering long sentences 
 without the least hesitation. After a conversation of about an 
 hour, he said, ' It is very cold on this grass, but I am so tired 
 I must lie down.' He soon after lay down, and remained quiet 
 the rest of the night. Next morning he had not the least 
 recollection of what had passed, and was not even aware of 
 having dreamt of anything." 1 
 
 In this case it is to be observed that the somnambulist 
 walked up-stairs while supposing himself already on the water's 
 edge, and only when he got to the floor above did he fancy 
 that he had reached the boat. He recognised no inconsistency 
 in the supposed boatman talking freely on botanical matters, 
 or inquiring about the prizes which had been gained, though 
 he was embarrassed by a reference to his own name, obviously 
 because of reluctance to boast of his honour, not because of any 
 surprise that the boatman should be able to name him. Along 
 with these features of mental exercise, there was a sense of 
 weariness which inclined him to lie down in bed, and this it is 
 doubtless which operates in ordinary experience to keep us in 
 bed, notwithstanding that we are quite actively engaged in our 
 dreams. 
 
 The state of trance, whether it may be classified under aggra- 
 vated hysteria, or regarded in a still more serious light, as it 
 involves some degree of brain disorder, might be reserved for 
 the following chapter. But it is well to introduce such brief 
 reference as will suffice, while the subject of unconscious- 
 ness is under consideration. This state, in the variety of illus- 
 trations of it which are recorded, is a direct result of a disordered 
 nervous condition. Commonly there is a low state of physical 
 strength, and with that often an excessive and abnormal 
 excitement of the nerve system. There are many recorded 
 1 Abercrombie's Intellectual Powers, 12th ed., p. 239. 
 
xil.] WEARINESS, SLEEP, AND UNCONSCIOUSNESS. 357 
 
 examples of liability to this condition during a period of weak- 
 ness or suffering. I take two illustrations from " Cases of Obscure 
 Nerve Disorder/' given by Mr. J. Handfield Jones, M.B., of St. 
 Mary's Hospital, London. The first is the case of a railway 
 porter, aged thirty-four, who was brought to the hospital " per- 
 fectly insensible," and limbs "quite relaxed." He had met 
 with no accident, and had not suffered from any epileptic 
 attack. He was brought in "on February 3, 1874, about 2 
 a.m.," and continued in the unconscious state, notwithstanding 
 cupping and use of enema, "but in the course of the morning 
 he became quite rational and conscious." He did not know 
 where he was till 9 A.M. of the following day. Still " he was 
 very stupid for some time," and said that " he felt very queer 
 still, and his head was giddy." He then explained that he had 
 for some time before been " giddy if he stooped." " He had 
 been feeling giddy for fourteen days, after lifting a weight; 
 when he rose up his head would swim for a time. The day 
 before the night of his attack, he had been at work at the 
 station from 1 p.m. to midnight ; he had felt poorly, and had 
 taken some brandy twice ; was going home when he became 
 insensible. The last thing he remembers was getting another 
 porter to take his list to the office. He did this because he 
 found himself getting worse, — more giddy and stupid." Mr. 
 Jones gives it as his opinion that the case indicated " a disorder 
 of febrile and catarrhal nature," leading to impaired cerebral 
 power. Besides the possibility of a weakened condition under 
 influenza, account must be made of over-work, probably lifting 
 too heavy weights, and to these must be added aggravation of 
 cerebral excitement in the turmoil of station work. Twenty- 
 three days after admission he is reported, " going on quite well, 
 — only very weak." Soon after, he left the hospital, but came 
 back about a month after as an out-patient, and so continued 
 for several weeks, and then went to the country for a time, and 
 is reported on June 15 as at work and gaining strength. He 
 never had a return of the unconsciousness, with cerebral 
 paralysis. 1 
 
 A case more exactly presenting the conditions of what is 
 commonly named trance is the following, — Case 1 2 in the series 
 1 Medical Times and Gazette, 1874, vol. ii. p. 130. 
 
358 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 * 
 
 given by Mr. J. Handfield Jones, and named by him "Hysterical 
 Trance." It is the case of a female, aged seventeen, of whom 
 he says that "she was a healthy girl," and "never had any 
 epileptic fits." She had been attacked on the evening of the 
 20th October 1870, and Mr. Jones saw her on the following 
 morning about 1 1 a.m. When the attack came on, " she had 
 been up-stairs, and on coming down shrieked out and became 
 insensible." She continued " quite insensible and motionless " 
 for about twenty-six hours, when she seems to have come out 
 of the unconscious state as suddenly as she had passed into it. 
 " She asked for and drank some tea, and ate a little bread and 
 butter, but soon relapsed into her former state." Liability to 
 pass into the trance continued for some weeks. Several times 
 in the course of a day she would become conscious, and appear 
 as if nothing were wrong, and yet soon pass again into insen- 
 sibility. About a week after the first attack she "became 
 delirious, had delusions, and struck the walls with her hands." 
 This was an unusual experience. When in the unconscious 
 state there were " no convulsions," but at times " her arms and 
 legs were rigid." When in this state during a visit made by 
 Mr. Jones the following facts were noted : — " No effect is pro- 
 duced by tickling the soles of the feet ; she seems quite un- 
 conscious. Her eyes are wide open ; touching of the eyelashes 
 causes no winking of the lids, and touching the sclerotic (see 
 above, p. 61) very little, but touching the cornea causes imme- 
 diate closure of the lids. The pupils are of medium size, and 
 seem insensible to light." 1 In course of a few weeks recur- 
 rence of the trance ceased, but a year and a half afterwards 
 there was a brief period during which the abnormal state of 
 things returned. Mr. Jones refers the case to " hysteria," and 
 in explanation of the facts occurring in the life of an apparently 
 healthy girl, " active and useful in the household," and not pre- 
 senting any features of temperament or habits of life " such as 
 would lead one to anticipate the occurrence of hysterical dis- 
 orders," he says that " a cataract which subsequently appeared 
 probably indicated some inferiority of the nervous system." 
 Three members of the family seem to have suffered from their 
 eyes, and Mr. Jones concludes that the trance state may have 
 1 Medical Times and Gazette, 1875, vol. ii. p. 184. 
 
xn.] WEARINESS, SLEEP, AND UNCONSCIOUSNESS. 359 
 
 been a consequence of " developmental affinity of the eye and 
 of the brain." The case is one of a class not infrequent, and 
 is of much value to those studying the relations of mind and 
 brain. There is complete coma, showing a torpor of the great 
 nerve centres, and also of the spinal centres, and at times nerve 
 excitement throwing the muscles into a rigid state. And this 
 nerve prostration is not associated with any dulness or stupidity 
 when consciousness returned, as there was in the preceding 
 case. " Her faculties were then and at other times perfect ; 
 in fact her friends say that she seemed shrewder and keener 
 than usual." 
 
 A third phase of abnormal condition of the nerve system is 
 presented by the " mesmeric sleep." This is an artificially induced 
 sleep, in which the patient is unconscious of all around, save 
 that he is completely under guidance of the operator. Experi- 
 menting with the "mesmeric sleep" was a favourite occupation 
 with the students who gathered in the drawing-room of the late 
 Sir W. Hamilton while he was Professor of Philosophy in Edin- 
 burgh University. By a series of passes made with both hands 
 of the operator, which are brought from above the head down 
 over the eyelids, and are returned by a slightly curved move- 
 ment behind the back, a state of artificial sleep is induced, out 
 of which the patient is brought by a reversal of the passes, 
 that is, from below the face upwards, with occasional blowing 
 upon the eyelids. This sleep is as readily induced by concen- 
 trating attention on a coin in the palm of the hand, without 
 resorting to any passes. During the " mesmeric trance," the 
 excitement in many cases becomes great, the pulse sometimes 
 rising to 1 20 in a few minutes. Frequent submission to the 
 influence tends to induce an abnormal condition, and by-and- 
 by establishes a dominion of a most pernicious kind, which is 
 not readily broken. The tendency to yield to the influence 
 increases at a rapid ratio. Hence it is that public operators are 
 pleased to have the same persons to operate upon from night 
 to night. 
 
 The "mesmeric" trance is in one aspect an artificial sleep; 
 in another an abnormal condition of brain analogous to the 
 unconsciousness of the trance state described above ; and in 
 another aspect still, completely differing from the trance, inas- 
 
360 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 much as there is an established relation between the operator 
 and the patient, making it easy for the former to communicate 
 with the latter. It is a voluntarily induced state, for though 
 the person is thrown into the trance, by means of the passes 
 made over the head, the result is accomplished only if he 
 voluntarily yield to the influence. By determination to the 
 contrary, turning the attention away from what is done, and 
 concentrating it on something contrary, the most resolute 
 efforts of the mesmerist prove fruitless. In further illustration 
 of this, a person may, by no other influence than his own, throw 
 himself into this trance, which in such a case would continue 
 in the form of a natural sleep. The unconsciousness belonging 
 to the "mesmeric" trance is one which seems to affect the sen- 
 sory system more than the motor. There is neither unnatural 
 flexibility, nor is there rigidity of the muscular system ; but 
 susceptibility to pain seems considerably diminished. Obser- 
 vation of those in the state makes it difficult to decide whether 
 there is an actual insensibility to pain, or a disregard of it 
 under excitement, in accordance with well-known facts in the 
 ordinary waking state (see p. 325). There is unusual sensi- 
 bility to the influence of the operator, the degree of which, 
 however, varies, being much greater in the case of those of 
 excitable temperament. The power of the operator is such that 
 his words carry conviction, and convey impressions of the most 
 vivid order to the patient. While the latter is as oblivious to all 
 around him as if he had fallen asleep in his chair, the mesmerist 
 can communicate with him as freely as any one may with the 
 somnambulist, as in the case described above (p. 355). Under 
 the representations made by the operator, the mesmerised 
 person shows great quickness of imagination, associated with 
 great susceptibility, which strangely contrasts with the in- 
 sensibility to touch, The operator, placing a tumbler of water 
 in his hand, may tell him that the water is very cold ; he will 
 taste it, and admit that it is so. If he be next told that it is 
 getting colder and being frozen, he will appear to recognise it 
 by the touch, and will visibly shiver. If it be now suggested 
 that the water is growing warm, he will appear at once to feel 
 the change, and will state that he does. If it be further de- 
 clared that the water is now growing very hot, he will get out 
 
xn.] WEARINESS, SLEEP, AND UNCONSCIOUSNESS. 361 
 
 his pocket-handkerchief, and wrap it around the glass to save 
 him from having his fingers burned. If it be said that the 
 water has begun to boil, he will scream and throw the glass 
 from him in alarm. Such 'phenomena as these help to illus- 
 trate the vividness of imagination often characteristic of our 
 dreams. The mind which, at the mere suggestion of another, 
 can vividly represent to itself such sudden and violent changes 
 as those described, and thereby awaken sensory impressions, 
 can do the same for itself without direct suggestion from 
 another. The mind which in such slumber is capable of inter- 
 preting what is said, is capable also of carrying out its own 
 lines of thought, utilising the power of imagination to suit the 
 present exercise, and operating upon the sensory centres, just 
 as in the somnambulistic excitement it acts upon the motor 
 centres. Thus the mesmeric phenomena, taken with those of 
 somnambulism, illustrate the fact that clear and consecutive 
 intellectual action is compatible with what we describe as a 
 state of " unconsciousness." A theory of mesmeric influence it 
 will be exceedingly difficult to construct. The mesmeric trance 
 belongs to the class of obscure nerve affections of an abnormal 
 kind. The state is such as to involve " unconsciousness " in 
 some degree, along with " consciousness " of certain phases of 
 activity ; but the patient comes out of the state without any 
 recollection of what has been said and done. Investigation 
 into the facts is thus seriously restricted. In acknowledg- 
 ment of this it seems reasonable that no special argument in 
 support of the distinction between mind and brain should be 
 founded upon them. But this much they do illustrate, that 
 active intellectual exercise is compatible with the state of 
 sleep, and nevertheless the agent may have no recollection of 
 his doings when he awakes from his slumber. 
 
362 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 CHAPTEE XIII. 
 
 BRAIN DISORDERS. 
 
 That a complicated organism like the brain must be ex- 
 ceedingly liable to disorder, and that such disorder, when it 
 appears, is a purely physical disorder, — a disease of the tissue, 
 — or restraint on its action, are considerations which must be 
 acknowledged universally. As, however, it is admitted that the 
 brain is the organ of mind, — and this is expressly maintained 
 by those who hold the distinct nature and higher functions of 
 mind, — all disorder or disease of brain must present facts of 
 importance towards constructing a theory of the relations of 
 mind and brain. The disturbed state of the brain, with all the 
 physical and mental peculiarities which appear in consequence, 
 must throw great additional light on the functions of the brain 
 and the scientific interpretation of mental phenomena. The 
 Pathology of the Nerve System is, therefore, a department of 
 study specially important to the psychologist. 
 
 Prom what has been already said as to the action and re- 
 action of mind and brain, it is clear that any disorder affecting 
 the brain must, according to its nature and extent, affect the 
 mind. In cases of slight disturbance, the effect may not be 
 such as to be marked in the consciousness of the individual 
 himself, and may not attract the notice of any observer, but 
 every change on the cellular substance of the nerve centre is a 
 change relatively to the mind of which it is the organ. Every 
 check on the functional activity of the organ must have a 
 bearing upon the possible activity of the mind in its govern- 
 ment and use. 
 
 These very obvious positions may suffice to indicate that the 
 work of the pathologist concerned with the treatment of those 
 suffering from brain disorder is intimately related to the whole 
 subject of study here under consideration. At the same time, 
 
xiii.] BRAIN DISORDERS. 363 
 
 it is needful to remember that the pathologist is dealing with 
 a physical disorder, and is seeking the cure of physical disease, 
 as truly as any specialist in the medical profession who has 
 devoted himself to the study and treatment of diseases of the 
 lungs, the heart, the stomach, or any other organ. When, how- 
 ever, we speak of the pathology of brain, the organ is so closely 
 connected with the mind, that there is special risk of obscuring 
 the fact that, as in the other cases named, we are dealing with 
 physical phenomena. We have come even systematically to 
 speak of " mental diseases " and their treatment, as if the 
 phrase were the appropriate designation in the circumstances. 
 Yet it is singularly inappropriate, except in the vocabulary of 
 those with whom- brain disorder and disorder of mind are 
 synonymous. The closeness of relation between mind and 
 brain, — the admitted fact that disturbance of the one, as a rule, 
 involves disturbance of the other, — may sufficiently account for 
 conventional usage. But the power of conventionalism is the 
 only explanation of the persistence of the phrase "mental 
 diseases," to describe a class of disorders as truly physical as 
 disorders of the eye or ear. Every one devoted to the patho- 
 logy of brain must, indeed, take account of mental phenomena 
 as throwing light upon the probable condition of the organ 
 entirely concealed from his observation, yet for the relief of 
 which he must prescribe. No oculist would disregard the 
 statement of a patient who mentioned that he often saw lumi- 
 nous appearances floating before him. No aurist would treat 
 slightly the statement made in consultation that the patient 
 experienced uneasiness and inability to understand what was 
 said when words were loudly spoken. And, on precisely 
 analogous grounds, the physician dealing with morbid condi- 
 tions of brain, must mark and classify evidence as to the feel- 
 ings, dispositions, and thoughts of his patients, which have a 
 distinct value for his purpose, if only they are accurately in- 
 terpreted. If he is dealing with an organ whose recognised 
 function it is to convey impressions to the mind, — an organ 
 which is, as Feuchtersleben said, "the focus of represented 
 images," and " essential to the manifestation of psychical 
 action," 1 he must concentrate a large portion of inquiry in each 
 1 Medical Psychology, translated for Sydenham Society, p. 105. 
 
364 THE RELA TIONS OF MIND AND BRAIN. [chap. 
 
 case on the experience and action of the mind, in order to reach 
 an accurate diagnosis of the condition of the brain. This then 
 indicates the true relation of two distinct orders of facts, known 
 by completely different methods, a relation which quite readily 
 explains the general tendency to speak of " mental diseases," 
 and even to employ the phrase in academic and scientific 
 usage, though it is recognised that express reference is made to 
 brain disorder or restraint. There is nothing in the usage 
 which carries a single tribute of prima facie evidence for the 
 theory that mental phenomena are merely manifestations of 
 organic action. The distinction and relation of the two orders 
 of facts has been well stated by Dr. Ferrier in these words : — 
 " It is essential to bear in mind that the functions and diseases 
 of the brain manifest themselves under two aspects — the 
 psychological and the physiological : phenomena which appeal 
 to two distinct methods of investigation — the subjective and 
 the objective. . . . That the brain is the organ of mind no 
 one doubts ; and that, when mental aberrations, of whatever 
 nature, are manifested, the brain is diseased organically or 
 functionally, we take as an axiom." 1 If there is defect of the 
 optic nerve involving a measure of colour-blindness, the mind 
 must be proportionally restricted, — we often say " misled," — as 
 to distinction of colour, but there is not in this any proof of 
 deficiency in mind. If deficiency or disorder extend higher up 
 on the nerve centre, the relation of facts is in no degree altered, 
 — there is a physical basis to account for the disturbance, hut 
 it is not thereby shown that there is a disorder of mind. On 
 the contrary, we may have clear evidence that the mind deals 
 accurately with the circumstances. The man restricted in dis- 
 crimination of colours is not only observed by others to be 
 defective in vision, but the fact is known to himself, and his 
 judgments of colour are voluntarily adapted to the recognised 
 defect. And just so it is that, when more serious brain dis- 
 order threatens to carry disorder into the mental processes 
 also, the patient observes the fact, and adopts means to ward 
 off the threatened danger, or to guard against acting under 
 misconception. We may, on the ground of evidence already 
 adduced, indicate the point from which we start our investi- 
 1 The Localisation of Cerebral Disease, p. 5. 
 
X1II -1 BRAIN DISORDERS. 365 
 
 gation of pathological facts, thus, — any degree of injury to the 
 nerve centre may imply disturbance to the mind, and the 
 greater the injury of the organ, the greater the disturbance to 
 the mind, of which it is the organ. Or, to put it from the 
 physiological point of view, and apart from polemic interests, 
 we may take the words of Dr. Brown- Se'quard, when speaking 
 of the "grey matter of the upper part of the brain:" — "You 
 may subtract from this, by disease or otherwise, say the upper 
 third, and still you have the nerves and the nerve cells, and 
 the processes can be carried on ; but in the progress of such 
 destruction downward there would eventually be reached a 
 point where the functions of the brain could no longer exist." 1 
 Such a hypothetical method of diminishing the quantity of 
 cellular substance does not in any way illustrate the ordinary 
 history of disease in the organ, nor does it satisfactorily meet 
 the problems as to "localisation," but it puts in a clear light 
 the introductory consideration which must influence all our 
 study of pathological evidence. 
 
 Without attempting an exhaustive classification of the facts, 
 or considering the subdivisions which have been suggested by 
 the various authorities on brain disorder, the purposes of the 
 present inquiry may be met by a threefold distribution of the 
 phenomena. These may be stated thus : — 1. Imperfect de- 
 velopment of the organ; 2. Disease of greater or less extent 
 in the brain ; 3. Violent injury to a healthy brain. The classi- 
 fication is not sufficiently exhaustive to include the vast 
 variety of cases which come under professional treatment, but 
 it marks clearly distinguishable classes, and meets the require- 
 ments of the present investigation. The first class includes 
 cases of imbecility apart from disease ; the second, cases of in- 
 sanity, with mania ; the third, cases of suffering and restraint 
 in mental activity, without insanity. 
 
 I. Imperfect development of brain. — It has been already re- 
 marked (p. 22) that when the brain falls below 30 ounces in 
 weight, there is imbecility, and it is to be noticed along with 
 this, that where there is such an undeveloped nerve centre, 
 there is feebleness of body as well as "feebleness of mind." 
 Accordingly the muscular condition, as truly as the range of 
 1 London Medical Record, 1874, vol. ii. p. 334. 
 
366 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 mental activity, is an index of the state of the brain. It even 
 becomes an obvious subject of inquiry whether the half-de- 
 veloped physical condition, recognised equally in the nerve 
 system and in the muscular, is not the explanation of those 
 facts which we describe by the current phrase " mental weak- 
 ness." Quite appropriately, from this point of view, it has 
 been remarked by Dr. Maudsley, as the result of long observa- 
 tion in this department, that "the superiority of the human 
 mind over the animal mind seems to be essentially connected 
 with the greater variety of muscular action of which man is 
 capable : were he deprived of the infinitely varied movements 
 of hands, tongue, larynx, lips, and face, in which he is so far 
 ahead of the animals, it is probable that he would be no better 
 than an idiot, notwithstanding he might have a normal de- 
 velopment of brain." 1 Undeveloped brain implies an unde- 
 veloped physical condition ; such a condition implies the im- 
 pairment or loss of many of the appliances which contribute 
 to intellectual development. On the other hand, if large use 
 of muscular action be a condition of normal mental develop- 
 ment, mental power is a prerequisite (see p. 298) for accom- 
 plishing the " greater variety of muscular action of which man 
 is capable." Such facts, lying on the threshold of the subject, 
 are not unfavourable to the theory that mind is a higher order 
 of being, but readily harmonise with it. If mental phenomena 
 are merely the product of a healthy exercise of organism, 
 " mental weakness " is caused by physical weakness. If mental 
 activity discovers the presence of a power higher than any- 
 thing which belongs to organism, the " mental weakness '' 
 appears in the impairment or lack of the physical appliances 
 in the use of which mind exercises its power, and manifests 
 itself to observers. Thus far, it is obvious, preliminary facts do 
 not bar the way of entrance to this field of inquiry against 
 either of the theories propounded. 
 
 We thus come to the question, To what extent is imbecility 
 accounted for by imperfect development of brain ? At an early 
 stage of this inquiry we have seen that neither is size of brain 
 nor weight a sure test of brain power. Much depends upon 
 quality of the nerve cells, and convolutions of the grey matter. 
 1 Body and Mind, p. 30. 
 
xui.] BRAIN DISORDERS. 367 
 
 But it is beyond doubt that there is a limit, beneath which 
 there is " imbecility." Below 30 ounces in weight, 1 or below 
 17 inches in circumference of cranium, 2 uniformly implies im- 
 becility. 
 
 In the large number of cases of idiocy, only a comparatively 
 small number come under the classification of microcephali, or 
 persons of small brain. This is a fact requiring to be specially 
 remarked. Only a small fraction of the idiocy or imbecility 
 appearing in the history of our race can be traced to imperfect 
 development of the organ of mind. " Idiocy is generally the 
 result of disease, not of smallness of the brain." 3 Several 
 scientific men of France, after thirty years of " measuring and 
 weighing," declared that "three-fifths of idiots have larger 
 heads than men of ordinary intelligence." 4 The simple expla- 
 nation is, that disease of brain in many cases results in enlarge- 
 ment of head, as at once appears by reference to Wagner's 
 Tables. To the same effect is the testimony of Professor Carl 
 Vogt : — " Cases of microcephaly are rare. The crania and the 
 brain of the microcephali are the most valuable objects in 
 pathological collections. Despite long continued researches, I 
 have, in the whole scientific literature, only found notices of 
 about forty cases, and even of these there are probably some 
 belonging to the category of idiotism from disease." 5 Dr. Ire- 
 land says, — "It is the rarest of all kinds of idiocy." After 
 giving a list of 31 cases, Vogt remarks : — " Of these thirty-one 
 cases, nine are of the female sex. In eight other cases, the age 
 of which is unknown, but the sex indicated, there is one female 
 case; there are thus about 25 - 6 per cent, or one-fourth of the 
 female sex." 6 Dr. Ireland, referring to Vogt's Mivwires, says 
 
 1 Turner's Anatomy, vol. i. p. 298. 
 
 3 Ireland on Idiocy and Imbecility, p. 79. For a large gathering of 
 measurements, see Thesaurus Craniorum, Catalogue of the Skulls of the 
 Various Races of Man, by Dr. Joseph Barnard Davis, selecting the letter B 
 in each case. Out of this list of 1500 skulls, I have gathered only 4 ex- 
 amples so low as 17 inches. There are 76 set down at 18 inches, — 4 European, 
 39 Asiatic, 4 African, 2 North American, 13 South American, 10 Australian 
 and Islands of the South East, 4 natives of the Western Pacific Isles. 
 
 3 Ireland's Idiocy, etc., p. 79. 
 
 4 Begum's Report, lb. p. 78. 
 
 6 Anthropological Review, vol. vii. p. 129. e lb. p. 135. 
 
368 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 that " many more have been recorded since the publication of 
 his monograph," and adds, "there are nearly twice as many 
 male microcephales as female." 1 " Few microcephales are of 
 ordinary stature, and many of them are mere dwarfs." 2 As a 
 rule, they do not live long. In Vogt's table of 31 cases, only 
 six are above 20 years of age, and there are ten under 10 years 
 of age. 
 
 While, then, the imbecility arising from a small size of brain 
 is comparatively uncommon, there are, nevertheless, examples 
 sufficiently numerous to guide us to definite conclusions. When 
 dealing with the comparative structure of brain in the ape and 
 in man, it was shown (p. 161) what is the contrast between the 
 ape's brain and the undeveloped human brain. There is, there- 
 fore, no need for discussion of the subject at this point. Eestrict- 
 ing attention here to the cases of undeveloped brain in the human 
 race, there are very striking contrasts presented in the several 
 examples. This is well illustrated by two cases reported from 
 Italy, the one girl being named Antonia Grandoni, the other 
 Cioccio, which may be readily compared, being reported upon 
 by the same observer, and both present very small weights and 
 measurements, while illustrating great diversities of "mental 
 action." They are reported by Professor Cardona, and a micro- 
 scopic examination of the brain was made of the case of the 
 former by Dr. Severini of Perugia. 3 The girl upon whose case 
 interest concentrates as the most singular example of micro- 
 cephaly known, Antonia Grandoni, was born in 1830, and died 
 in 1872. " Her father was a boatman ; her mother was a woman 
 of small stature, who died of consumption ;" Antonia's brother 
 and sisters were all healthy children. Her brain, when weighed, 
 •was found to be only 289 grammes, little more than 9 oz., one 
 of the lightest on record, and a wonderful amount below the 
 boundary line of 30 oz., under which imbecility appears. Com- 
 parison with other cases may be made by the following enume- 
 ration, reckoning 32 grammes = 1 oz. 2 dr. "Among the cases 
 published, Wagner had one whose brain weighed 300 grammes ; 
 Griesinger, one of 576 grammes; Theile, of 294 grammes; 
 Gore, of 283 grammes; Marshall, of 238 grammes. ... In 
 none of these did the intelligence approach that of Grandoni ; 
 i Idiocy, p. 81. 2 lb. p. 80. a Ibm p- i 03 . 
 
xin.] BRAIN DISORDERS. 369 
 
 indeed in all these instances the mental power was of the 
 lowest." 1 
 
 The degree of intellectual activity shown by Antonia Gran- 
 doni is wonderful, and much greater than that shown by 
 Cioccio, the external circumference of whose skull was less, 
 though the brain was larger. Of Antonia Grandoni, with her 
 9 oz. of brain, Professor Cardona reports : " She has good sight 
 and good hearing, attends to what is said to her, and gives 
 satisfactory answers; she sometimes smiles, but more to do 
 like those around her than from hilarity. She sets herself to 
 work like any other girl." 2 "She was not much later than 
 usual in beginning to walk and speak, but her intelligence was 
 inferior to children of her age. She, however, learned in time 
 to do easy work about the house, and to go out of doors to buy 
 provisions. She was fond of learning amorous poetry, and 
 showed erotic tendencies. On getting older, she took to 
 wandering about, and might be seen dancing, with grotesque 
 movements, to her own singing. For many years she led a 
 wandering life, an object of curiosity, of pity, or of ridicule to 
 all." In this account there are some puzzling features, but the 
 degree of intelligence stands out as the singular fact in the 
 case. The wandering life allowed to her was a great misfortune, 
 as was the neglect of systematic educational efforts, for there 
 can be little doubt that the fondness for amorous poetry could 
 have been widened out to something greatly more enlarged and 
 elevating. The contrast between the intellectual activity in 
 her case and the almost complete absence of it in the case of 
 Cioccio, is thus dwelt upon by Professor Cardona: — " The small- 
 ness of the brain of Cioccio induced stupidity, idiocy, deaf- 
 muteness — in short, simply animal life ; the poverty of brain 
 of our Grandoni, in that small size accorded to it by nature, 
 could admit of a sensibility, an intelligence, and an education 
 which has not fallen much short of the average of her country- 
 women." This sentence, showing, as it does, a genuine and 
 valuable interest in the case, is apt to be misleading. When 
 we speak of the stupidity and idiocy of Cioccio, we must con- 
 sider that " deaf-muteness " implies a series of barriers to the 
 development of intelligence. This has been illustrated by the 
 1 Ireland's Idiocy, p. 110. 2 lb. p. 104. 
 
 2 A 
 
37° THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 breaking-up of these barriers in the history of Laura Bridgman 
 (p. 296). On the other hand, we can hardly allow, in view of 
 the description, that the intelligence of Antonia Grandoni at 
 all approached the average intelligence of her countrywomen. 
 Without saying so much as this, her intellectual activity is a 
 marvel with a brain of 9 oz. In the case reported by Mr. Gore, 
 also of a female, the brain weighed 10 oz. 5 grains (avoirdupois), 
 or 283 grammes, and that " after the membranes and vessels had 
 been removed." This is only 6 grammes lower than Grandoni. 
 Of the woman to whom Mr. Gore refers, he says, " she could 
 say a few words, such as 'good,' 'child,' 'mama,' 'morning,' 
 with tolerable distinctness, but without connection or clear 
 meaning, and was quite incapable of anything like conversa- 
 tion." l The case reported by Professor Marshall is that of an 
 idiot boy who died at twelve years of age, the entire encephalon 
 weighing only %\ oz. 2 Unfortunately there is not in the report 
 of this case a single remark as to the degree of intellectual 
 activity manifested by the boy. 
 
 When Antonia Grandoni was brought to the hospital, where 
 she afterwards died, the following results, from regular obser- 
 vations of her conduct, are noted : — " The walk was slow and 
 hesitating ; but she was a good and agile dancer. She was gay 
 and sociable in her disposition, and never complained, except 
 for bodily pain, but the idea of death disturbed her. She was 
 always quiet and obedient, and when hindered doing anything, 
 she showed grief, but no resentment. She felt for the suffer- 
 ing of others. She knew that her head was small, and an 
 object of attention. She was very careful in her dress, and was 
 fond of attracting the notice of the other sex. She remembered 
 those who were kind to her, was glad to see them, and would 
 go in search of them when they did not appear. When visitors 
 came to the hospital, she desired to be noticed, and was dis- 
 appointed if she were neglected. She was fond of talking about 
 marriage, liked' singing and dancing, could play well upon the 
 cymbals, and was anxious to get her companions to dance to 
 them. She showed a good memory for names of persons and 
 
 1 Anthropological Review, vol. i. p. 169. 
 
 2 lb. Appendix, Transactions of Anthropological Society of London, p. 
 
xm.] BRAIN DISORDERS. 371 
 
 things, remembered places and bygone events, but had no 
 memory of time. She answered questions satisfactorily, adding 
 information without being asked. She had the sentiment of 
 good and evil, and made sensible remarks upon the conduct of 
 her companions. She was religious through imitation and 
 habit, and behaved well in church. Every attempt to instruct 
 her was without success." 1 In view of this narrative, there is 
 no room to hesitate as to Dr. Ireland's statement: " I have little 
 doubt, by a well-planned education in childhood, her mental 
 power could have been increased and her wandering and erotic 
 tendencies repressed." As little room is there for questioning 
 the following : — " Any one who compares the cranial capacity of 
 a few microcephalic idiots with the intellectual manifestations, 
 will hardly fail to notice that the one does not bear any de- 
 finite proportion to the other." 2 If for a moment we recur 
 to recorded brain weights of apes, taking these as given (p. 
 160), 9f oz., 13J oz., 12 oz., the force of the remark made by 
 Professor Marshall becomes obvious when he " alluded to the 
 supposed similarity between the brains of idiots and those of 
 the higher apes, and maintained that the objects are not com- 
 parable, as the brain of the ape, though low, is perfect, but that 
 of the microcephale is essentially imperfect." 3 
 
 Fortunately we have the results of a careful examination of 
 the brain of Antonia Grandoni, made by Dr. Adriani. In his 
 report, the points of chief interest are the following: — "The 
 hemispheres were the least developed. The pons, the medulla 
 oblongata, the tubercula quadrigemina, the peduncles, and the 
 cerebellum fell much less below the ordinary dimensions. The 
 greatest breadth of the brain at the middle was 85 millimetres, 
 and 68 millimetres at the base of the anterior lobes. The 
 cerebral hemispheres were perfectly symmetrical: they were 
 100 millimetres in length, and were shortened posteriorly, so that 
 the cerebellum was left uncovered for about 70 millimetres. 
 The fissures of Sylvius and Eolando were well marked. All 
 the cerebral lobes were small ; the parietal and occipital were 
 smaller in proportion to the frontal and temporal lobes. The 
 sphenoidal and the anterior and posterior central convolutions 
 
 1 Ireland's Idiocy and Imbecility, p. 106. 2 lb. p. 112. 
 
 3 Anthropological Review, vol. i., App. p. x. 
 
372 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 were also proportionally well developed. The convolutions 
 of the frontal and temporal lobes were more complicated and 
 better developed, and more numerous than those of the parietal 
 and occipital. The most notable anomaly of the brain was a 
 shortening and slight thinning of the corpus callosum." 1 While 
 the hemispheres were the least developed part of the encephalon, 
 their deficiency appeared most to the rear, leaving the frontal 
 relatively conspicuous. This fact harmonises well with the 
 view commonly taken of the frontal region. On the other 
 hand, Bischoff s case, — Helene Becker, — illustrates a compara- 
 tively prominent frontal region, with a falling away towards 
 the rear, which assumes nearly the form of an angle, while her 
 intellectual activity was so slight that "she knew her own 
 name, but otherwise paid very little attention to what people 
 said to her. She could only speak one word, but used two 
 sounds." 2 The remark as to the corpus callosum deserves 
 notice, but over against it we must place the case reported by 
 Professor Malinverni, of the University of Turin, which is that 
 of a man, aged forty, " who during life had shown no signs of 
 alteration or deficiency of the intellectual faculties," yet, on 
 examination of the brain, it was found " that the corpus cal- 
 losum was entirely wanting, together with the septum lucidum, 
 and the great cerebral convolution which surrounds the corpus 
 callosum," The cerebral mass, when viewed externally, did 
 not present any peculiarity," but " the convolutions at the base 
 were indistinct, specially those of the frontal lobe." 3 
 
 The microscopic examination of the brain of Antonia Gran- 
 doni by Dr. Severini brought out the following results : — " No 
 remarkable difference was found in the structure or proportion 
 of the nerve corpuscles ; . . . there was a remarkable abund- 
 ance of fundamental tissue, especially in the cortical matter of 
 the brain, which made the nerve cells appear scarcer than 
 usual ; . . . the prevailing form of nerve cell . . . was the tri- 
 angular one, with an oval or round nucleus, — few displayed the 
 pyramidal form; the structure of the blood-vessels appeared 
 normal ; if anything they were somewhat larger than usual." 4 
 
 1 Ireland's Idiocy, p, 108. 2 lb. p. 113. 
 
 5 London Medical Record, 1874, vol. ii. p. 319. 
 4 Ireland's Idiocy, p. 109. 
 
xin.] BRAIN DISORDERS. 373 
 
 The first and last of these statements are favourable to 
 functional activity ; the others are obviously unfavourable, and 
 make the intellectual manifestations in the life of Grandoni 
 all the more remarkable. 
 
 Grandoni's case cannot be taken as an illustration of ordi- 
 nary examples of microcephaly ; but as a decidedly exceptional 
 case, it has been the subject of special investigation, and is 
 suggestive as to the chief remaining point of inquiry here, — 
 the possibilities of education. The degree of intellectual 
 activity appearing in her case, even under all the disadvan- 
 tages of her neglected and wandering life, makes it clear that, 
 had systematic training adapted to her mental condition been 
 provided in her youth, she would have led a greatly higher life. 
 
 We have now to consider whether, in the case of persons of 
 undeveloped brain, it be possible successfully to prosecute in- 
 tellectual and moral training. The question connects our 
 inquiry with that previously raised as to deaf-mutism, and is 
 naturally regarded as a continuance, in altered form, of the 
 problem presented by the case of Laura Bridgman (p. 296). 
 In this department our most reliable witnesses are those who 
 have devoted themselves to such educational work. Their 
 testimony is that the work of education has been successfully 
 carried on in a large number of cases. And, what is of special 
 importance here, there is no educationist of experience in 
 this peculiarly difficult but noble department of service to 
 humanity, who suggests that effort should be directed, in the 
 first instance, exclusively on the physical condition. It is a 
 maxim with them all that the physical and mental must go 
 together, involving two entirely different forms of exercise for 
 each day. That is to say, they proceed with physical training 
 as a distinct undertaking, with the view of developing physical 
 powers, muscle, nerve, and brain ; and with mental training, as 
 something different, with the view of developing thought, self- 
 government, and self-respect. Thus Dr. Edward Seguin, in his 
 work specially devoted to an exposition of the "physiological 
 method," and as the result of large experience both in France and 
 America, has insisted on this, devoting one part to " physiological 
 education " and another to " moral treatment," — " the alliance 
 of the moral and physical sciences," as had been urged in the 
 
374 THE KELA TIONS OF MIND AND BRAIN. [chap. 
 
 report to the Academy of Sciences of Paris by MM. Serres, 
 Flourens, and Pariset. Dr. Seguin treats of the physical as 
 tributary to the mental, as indeed it must be in all human life : 
 — " Let it be one of our first duties to correct the automatic 
 motions, and supply the deficiencies of the muscular apparatus ; 
 otherwise how could we expect to ripen a crop of intellectual 
 faculties on a field obstructed by disordered functions V' 1 " Our 
 system of education is the process of accumulating in children 
 strength and knowledge; to create in men power and good- 
 ness." 2 While warning against "one-sided education," he 
 remarks on the special need for developing nerve power rather 
 than muscular, " paying more attention to the nervous, as being 
 the most shattered in idiocy." 3 On the other hand, Dr. Seguin 
 insists : " Whatever we want a child to do, and whatever might 
 be otherwise our special teaching to that effect, there are certain 
 moral conditions as necessary to our success as the technical 
 ones." 4 " Moral training of the children, one by many, several 
 by one, all by all, is one of the mainsprings of the present part 
 of our task." 6 " Our authority over them does not derive from 
 our superiority, but from the desire of elevating them to our 
 standard." 6 Dr. Ireland is equally decided : — " The treatment 
 should be both mental and physical ;" " to produce improve- 
 ment we must act upon the whole being, upon the body as 
 well as the mind." 7 The wants of the imbecile cannot be met 
 by concentrating effort on improvement of the physical condi- 
 tion first, with the view of attending to the mental afterwards ; 
 nor by attempting to instruct the mind, to the neglect of 
 physical development. Hence the force of Dr. Ireland's testi- 
 mony : — " It would seem at first sight that a private teacher, 
 such as a governess, who had the entire tuition of an idiot 
 child, would come to her task with great advantages on her 
 side, as she could devote her whole time to one pupil; but 
 nevertheless, I do not remember ever to have heard of much 
 being done in this way." 8 Very naturally does it follow upon 
 one-sidedness of treatment, that the remark should be made: 
 " It may be doubted whether it is a sadder sight to see the 
 
 1 Idiocy, and its Treatment by the Physiological Method, by Edward Seguin, 
 M.D., p. 94. 2 lb. p. 97. 3 lb. p. 99. * lb. p. 217. 
 
 6 lb. p. 218. ° lb. p. 220. ' Idiocy, p. 294. 8 lb. p. 296. 
 
xm.] BRAIN DISORDERS. 375 
 
 neglected idiot children of the poor, or the pampered idiot 
 children of the rich." 1 If an imbecile child is simply fed, 
 clothed, tended, and taken out for airing, he is allowed to 
 vegetate. He is tenderly cared for, yet is most seriously 
 neglected. Improvement will never come under this system ; 
 the hope of it has been surrendered. In this connection, 
 1 have read nothing more affecting than the words of Dr. 
 Langdon Down, Physician to the London Asylum for Idiots : — 
 " I have seen the relative of a noble, living in all the luxury of 
 a country house, so put aside by her sisters, senior as well as 
 junior, that she never ventoed on a remark, and at length 
 lost speech. I have seen the same girl at Normansfield pass 
 from monosyllables to thorough conversational language amid 
 the companionship and sympathy of her compeers." 2 
 
 In closing this line of evidence, it seems clear that the facts 
 connected with microcephaly or undeveloped brain, and educa- 
 tion of the imbecile, favour the view that mental existence is 
 something superior to brain organisation, though in all human 
 life the two are intimately connected. The general results 
 may be summarised in two or three sentences. 1. Very few of 
 the human race suffer in consequence of an undeveloped brain. 
 The great majority of instances of imbecility are to be assigned 
 to disease. 2. In cases of undeveloped brain, we do not find 
 a robust animal life with a feeble mental life, but feebleness of 
 body as well as " feebleness of mind," which last might better 
 be described in the words of Dr. Edward Seguin as a mind 
 " obstructed by disordered functions," a mind undeveloped 
 through lack of opportunity for its exercise under the ordinary 
 conditions. 3. Education of the imbecile is possible, notwith- 
 standing organic restraint. If physical and intellectual train- 
 ing are carried on together, the results are mutually helpful, 
 the advancing mind aiding development of body, and improved 
 physical condition opening the way for wider and more com- 
 plex use of intellect. The methods employed are distinct. On 
 the one hand, there is comparison, classification, reasoning ; on 
 the other, food, air, and muscular activity. 
 
 II. Disease of Brain. 
 
 The brain is liable to disease, as every bodily organ is, and 
 1 Idiocy, p. 297. 2 Ibid. p. 299. 
 
376 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 such disease should be regarded as a natural and inevitable 
 consequence of the interdependence of physical organs. The 
 designation, " mental diseases," has had a misleading and per- 
 nicious influence upon the public mind. It has been allowed 
 to circulate, as if it carried the suggestion that the sufferer had 
 " lost his reason," and was no longer within the circle of rational 
 beings. That a friend suffers from brain disease no more affects 
 his position as a man, or our relation to him, than if he suffered 
 from disease of the heart or of the lungs. The brain is in 
 many respects more liable to disease than other vital organs, 
 being so much more under the command of our will, and liable 
 to be overtasked. It is an irrational view of brain disease 
 which leads any one to regard it otherwise than as a physical 
 disorder, more or less serious according to the extent of the 
 disease and the hold it has obtained on the organ. That there 
 may be great moral culpability in the conduct which induces 
 such disorder is not to be overlooked and cannot be denied, 
 when the statistics of our asylums show that at least one- 
 third of the cases are to be attributed to drunkenness and a 
 licentious life. But, on the other hand, brain disorder may 
 be induced by natural causes as readily as any other form of 
 disease, and, like every other disease, may assume a curable or 
 an incurable type. When curable, the cure is effected primarily 
 by medical prescriptions, aided by suitable regimen, as in all 
 cases of physical disorder ; when, however, the patient is 
 amenable to reason, " moral means " are employed in acknow- 
 ledgment of the essential superiority of personal control. 
 
 As it is granted by all that brain is the organ of mind, 
 brain disorder must affect mental experience. Certain forms 
 of disturbed personal experience must be the indication of in- 
 cipient brain disease, while emotional disturbance is perfectly 
 compatible with a healthy condition. In harmony with the 
 former of these statements, it must be observed that in like 
 manner it is from personal experience that evidence can be 
 gathered as to heart disease and disorder of the stomach or 
 the liver. " How one feels " must be the question. Disturbed 
 experience is a common feature when subjected to disease. 
 The speciality belonging to brain disorder is, that it not only 
 involves experience of uneasiness and restraint upon the great 
 
xiii.] BRAIN DISORDERS. 377 
 
 nerve centre, but disturbance of mental processes. This fact 
 seems in strict accordance with the view that mind is an order 
 of existence higher than brain. If brain be the organ of mind 
 — the organ through which communication is carried to the 
 mind, and through which also communication is conveyed from 
 the mind — it follows that disorder will disturb the communica- 
 tion ; extending disorder will even gradually shut off the com- 
 munication, as the disease advances towards a fatal issue. The 
 matter of interest here is, the extent to which the phenomena 
 connected with a disordered condition of brain throw light on 
 the relations of mind and brain. 
 
 Disorder of brain may arise from many causes, of which the 
 following may suffice as illustrations ; — insufficient blood sup- 
 ply, inducing feebleness and brain wasting ; excessive blood 
 supply, causing pressure and uneasiness; febrile excitement 
 or inflammatory condition of the tissue ; pressure, as by forma- 
 tion of a tumour or accumulation of fluid; or inherited in- 
 stability of brain organisation, rendering its tissue liable to 
 take on morbid action. 
 
 A brief description of some of the conditions of brain as they 
 appear after death in the case of those whose physical and 
 mental state was recorded during life, is the best introduction 
 to this part of the subject. I am indebted to Dr. Clouston, 
 Lecturer in the University on Mental Diseases, and Superin- 
 tendent of the Eoyal Asylum, Edinburgh, for special facilities 
 for comparing pathological phenomena. The following cases 
 are selected as illustrative of different phases of disorder: — 
 1. A considerable portion of the brain shows signs of wasting, 
 and the membrane (jpia mater) is adhering to the brain, thereby 
 showing interference with the nourishment and normal condi- 
 tion of the organ. This is a very common phase of diseased 
 brain. 2. Brain of a young woman who died at twenty years of 
 age, and had been a sufferer from epilepsy. One hemisphere of 
 the brain is well developed, the other is quite undeveloped, 
 so as to be hardly one-half the natural size. She was very 
 liable to epileptic fits, under which, as Nothnagel puts it, two 
 symptoms may be regarded as essential — "first, the mental dis- 
 turbance, which generally manifests itself as a more or less 
 distinctly marked loss of consciousness ; second, motor dis- 
 
378 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 turbances, under the form of more or less extensive convul- 
 sions." x 3. A brain in which wasting of a portion of the 
 parietal lobe is manifest, leaving a considerable blank space 
 in the grey matter, and a darkish spot just beneath, as if fore- 
 boding the extension of the malady. 4. Brain in which the 
 wasting appears in the white substance, which is a more 
 unusual occurrence. In this case the wasting has extended 
 so greatly that only slight portions of the white matter remain, 
 and yet the person had been able to move the limbs to 
 some extent. 5. A brain in which serious traces of wasting 
 are seen in several places ; the membrane is adhering to the 
 grey substance, and the blood-vessels are hard and strong like 
 quills. This is a case in which loss of self-control was a marked 
 feature. The sufferer had been a clergyman, and had been sub- 
 jected to ecclesiastical discipline on account of inconsistency 
 of conduct. In the asylum self-government was established 
 only by the action of fear, a series of penalties having been 
 strictly applied in case of failure to conform to the rules laid 
 down, and of these that which made the most impression was 
 the withholding of tobacco. These five cases may be taken 
 as marked illustrations of the condition of brain in persons 
 said to be suffering under mental derangement. Disease has 
 been established in that organ, by means of which alone it 
 is possible for the mind to control and govern bodily actions 
 and tendencies. 
 
 If this be a description of the facts in such cases, as disclosed 
 by examination after death, all that has been recorded as to the 
 intellectual, moral, and physical aspects of the disordered life 
 of such sufferers can be adequately explained on the theory 
 which regards mind as a higher order of being controlling 
 physical organism in its normal condition, and so determining 
 the whole range of physical activity distinctive of man as an 
 intelligent being. The more carefully we classify, distinguish- 
 ing in detail the several phases of restraint as they appear, and 
 the intellectual activity of the patients suffering under these, 
 the more obvious does it become that the facts are such 
 as cannot be explained on the hypothesis that brain is the 
 
 1 Ziemssen's Cyclopcedia cf the Practice qf Medicine (translation), vol. xiv. 
 p. 266. 
 
xm.] BRAIN DISORDERS. 379 
 
 governing power in life. A rigid attempt to give a scientific 
 explanation on such a basis must show not only how truly the 
 disordered brain of the imbecile accounts for the imperfect 
 utterance, the feeble locomotion, and the comparatively slight 
 interest taken in things around ; but how it can account for 
 the recognition of persons well known, the interest which 
 their presence awakens, expectation of their coming, and the 
 readiness with which the sufferer adapts to his own modes 
 of thinking the suggestions offered by others. Or, to take 
 the opposite class of cases involving mania, a scientific ex- 
 planation which seeks to trace all to brain, must account 
 not only for the physical restlessness, the excitement, the 
 fear, and the violence which appear, but also for the purely 
 imaginary, and yet rationally consistent, account the sufferer 
 gives first to himself, and then to his physician, of his state 
 of excitement. We require a scientific account of premoni- 
 tions, so interpreted as to induce the sufferer to warn others 
 to keep off, showing a desire to avoid their injury; of the 
 interpretation of excitement by representations of having 
 been pursued or attacked; of the measures resorted to by 
 the sufferer in accordance with the rationalised account he 
 gives of his own trying situation; and of the possibility in 
 such circumstances of a measure of control being main- 
 tained under expectation of loss or penalty, if control be 
 surrendered. The combination of facts which will suffice 
 to guide the physician in his treatment of cases will not 
 meet the requirements of a scientific inquiry as to the rela- 
 tions of mind and brain. The physician is concerned with 
 appliances for nourishing the cerebral tissue, for soothing the 
 organ, and for stimulating its functional activity. He is 
 at the same time occupied with favourable mental action as 
 affording an essential feature in treatment, and is thus led 
 quite directly and regularly to take account of mental pheno- 
 mena. Still, this is done necessarily with a regard to the 
 relation of mental states to physical conditions, and not for 
 the purpose of constructing a scientific account of mental 
 activity, as that is restrained or stimulated by pathological con- 
 ditions. Even scientific works on the treatment of the insane 
 are not scientific treatises on the action of mind as affected by 
 
380 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 pathological phenomena, but rather on brain disorder as more 
 or less affected by mental states. This arises from the nature 
 of the case, and must be recognised if there is to be thorough- 
 ness in treating of two distinct scientific problems. The theory 
 of brain disorder is not a philosophy of the facts of mental 
 activity observed and classified in cases of cerebral disease. 
 And so, in like manner, a philosophy of mental activity under 
 such pathological conditions would not be a theory of brain 
 disorder, and would not be entitled to consideration as such 
 from those who are engrossed in practical treatment. This 
 distinction will, I believe, be readily acknowledged by medi- 
 cal authorities daily familiar with the details involved in 
 management of our invaluable retreats for sufferers under 
 cerebral disease. The distinction must be marked as quite 
 essential to the investigations involved, indicating the limits 
 of medical and mental inquiry, and the extent to which two 
 departments of study may contribute to each other's advance. 
 In view of this distinction, special value attaches to inves- 
 tigations of a wider kind, on the medical side, involving the 
 •relations of the two departments, such as those prosecuted by 
 Brodie, Holland, D. H. Tuke, Elam, Maudsley, and others. 1 
 
 In acknowledgment of the twofold problem, it is desirable 
 to consider in one line the facts which are specially connected 
 with the cerebral condition; in another, those which throw 
 light on mental experience. 
 
 Facts illustrating disordered cerebral condition. — Eeferenco 
 has already been made to the fact that a comparatively small 
 portion of the imbecility which exists can be traced to 
 undeveloped brain ; by far the greater portion of it resulting 
 from the action of disease. In explanation of the latter, much 
 is to be attributed to hereditary influences. The testimony of 
 facts is strong on this point. Dr. Maudsley has said : — " Idiocy 
 is, indeed, a manufactured article; and though we are not 
 always able to tell how it is manufactured, still its important 
 causes are known and are within control. Many cases are dis- 
 tinctly traceable to parental intemperance and excess. Out of 
 
 i Brodie's Psychological Inquiries, 2 Parta ; Holland's Essays, and Chapters 
 on Mental Physiology ; D. H. Tuke's Influence of the Mind upon the Body; 
 Elam's A Physician's Problems; Maudaley's Body and Mind. 
 
xiii.] BRAIN DISORDERS. 381 
 
 300 idiots in Massachusetts, Dr. Howe found as many as 145 
 to be the offspring of intemperate parents ; and there are 
 numerous scattered observations which prove that chronic alco- 
 holism in the parent may directly occasion idiocy in the child." 1 
 Here then we have idiocy in a large proportion of cases proved 
 to be an inheritance of physical infirmity, on account of phy- 
 sical indulgence on the part of one or both of the parents. It 
 is not shown to be the result of neglected education, or a con- 
 sequence of leading a wandering life in separation from the 
 intellectual influences of civilisation. If only the physical 
 nature be vigorous, there is an absence of the distressing mani- 
 festations of imbecility ; but, notwithstanding a robust phy- 
 sical constitution, there may be in multitudes of cases evidence 
 of an undeveloped mind, for which educational' appliances alone 
 are required. Children may inherit a degenerate organism 
 or a highly developed brain ; but in no case do they inherit 
 parental ignorance, as they do an enfeebled body ; nor do they 
 inherit the intellectual acquirements or knowledge of their 
 parents, as they may inherit physical aptitudes. The question 
 of heredity is still involved in so much obscurity that we are not 
 in possession of facts needful for a scientific explanation, but 
 such wide general data as those now referred to in the history 
 of idiocy are universally admitted by all engaged in classifica- 
 tion of cases under their own observation. If to the examples 
 of physical deterioration in the line of inheritance we add 
 cases of imbecility occasioned by accidental injury of the 
 head, and those following upon severe disease of brain, we 
 include almost the entire body of facts bearing on weakness 
 or atrophy. 
 
 If from imbecility we pass over to the other side of experi- 
 ence, where the phenomena of active insanity are under obser- 
 vation, we find here also that physical agents and excesses 
 are to a large degree causes of mania. In fact, mania in the 
 drunkard or debauchee is the preliminary in personal history 
 to imbecility in the history of his offspring. Happy indeed 
 are the children of such parents who have been born before 
 parental profligacy had reached its climax. Here, in outline, 
 is the sad history, as quoted by Dr. Maudsley from Morel, who 
 1 Body and Mind, p. 44. 
 
382 THE RELATIONS Of MIND AND BRAIN. [chap. 
 
 had traced " through four generations the family history of a 
 youth who was admitted into the asylum at Eouen in a state 
 of stupidity and semi-idiocy." In the case of the great-grand- 
 father, " immorality, depravity, alcoholic excess and moral 
 degradation, — killed in a tavern brawl." In the case of the 
 grandfather, " hereditary drunkenness, maniacal attacks, ending 
 in general paralysis." In the father, " sobriety, but hypochon- 
 driacal tendencies, delusions of persecutions, and homicidal 
 tendencies." In the youth himself, "defective intelligence, 
 mania at sixteen, stupidity, and transition to complete idiocy." 1 
 Such is the record of what alcohol and vicious indulgence 
 accomplished within four generations. In accordance with 
 these facts we find the annual reports of our lunatic asylums 
 testifying that intemperance and sexual irregularities and ex- 
 cesses are the chief sources of insanity, and that a smaller 
 proportion of existing insanity is to be assigned to the 
 disease and accidental injury to which organism is naturally 
 exposed. In the Psychological Betrospect of 1874, drawn 
 from the annual reports of all the asylums in the country, as 
 given in the Journal of Mental Science, July 1875, we read: 
 — " Most reports make reference to the part which intemper- 
 ance plays in the production of insanity. The time must be 
 drawing near when this horrible vice will be combated in a 
 more efficient and earnest manner than in time past. No one 
 can deny that drunkenness is the great sin of this country, and 
 that to its influence a very large proportion of insanity must 
 be more or less directly attributed." 2 Turning to the next 
 number of the same Journal, we find the President's address 
 to the Medico-Psychological Association, at its annual meeting 
 in 1875, by Dr. Duncan, President of the College of Physicians, 
 Dublin, in which we have the following declaration bearing 
 upon the increase of insanity : — " In my opinion, the monster 
 evil of intemperance, with its associated vices and its acci- 
 dental accompaniments, is the greatest of all the causes pro- 
 ducing the estimated increase. Sometimes it is alone account- 
 
 1 Mind and Brain, p. 45. 
 
 2 The Journal of Mental Science, published by authority of the Medico- 
 Psychological Association. Edited by Dr. Maudsley and Dr. Clouston. July 
 1875, p. 301. 
 
xm/1 BRAIN DISORDERS. 383 
 
 able for the overthrow of reason ; on other occasions it aggra- 
 vates and intensifies other causes operating along with it." 1 
 
 If next we pass from the causes to the manifestations of 
 disorder, we have a large proportion of physical results. Within 
 the cerebrum itself we have the marks of brain wasting, indi- 
 cated by such cases as those given above. In connection with 
 well-known symptoms of this state, we have more or less ex- 
 tended paralysis of the motor, and also of the sensory nerves. 
 Thus, on the physical side, we have marked loss of physical 
 power. No one proposes to deal with these disorders by edu- 
 cational appliances. When, on the other hand, an experienced 
 physician, such as Dr. J. Crichton Browne, tells us of the 
 value for checking brain-wasting and reinvigorating the organ, 
 of such things as cod-liver oil, hypophosphites of soda, tincture 
 of opium, and sulphuric ether, 2 he testifies that a physical 
 malady is under treatment. And when he adds these words : — 
 " Along with • the medical treatment of brain- wasting, dietetic 
 and moral treatment must be carefully attended to," the refer- 
 ence to " moral treatment " points to another class of facts 
 differing from the physical. 
 
 Besides the general fact of paralysis consequent on brain- 
 wasting, we have more specific knowledge which points to 
 the localising of the disorder. This is an essential feature in 
 this class of observations. The locality of the disease has a 
 direct relation with the locality of the paralysis. There is not 
 the slightest diversity of opinion as to this, however much 
 medical authorities may differ as to localising of functions in 
 the cerebrum. A certain amount of localising is recognised 
 on all hands. We have the sensory bulbs, and the basal 
 ganglia, about which there is no dispute, besides the lobes and 
 distinguishable convolutions of the cerebrum. Hence Dr. 
 Bastian has said : " We ought always to endeavour to discrimi- 
 nate the effects of injury to these several parts, since variations 
 in the seat of the lesion give rise to so many of the differences 
 in the total grouping of symptoms daily encountered at the 
 bedside." 8 The obviously accurate, and from a medical point 
 
 1 The Journal of Mental Science, July 1875, p. 336. 
 
 2 British Medical Journal, 1871, vol. i. p. 468. 
 
 3 On Paralysis from Brain Disease, by Dr. H. Charlton Bastian, p. 5. 
 
384 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 of view, quite essential, method of associating special phases of 
 paralysis with distinct parts of the cerebrum, is another "unmis- 
 takable proof that we are considering in such cases a purely 
 physical malady. Thus it is made out, — and could never be 
 seriously disputed, — that one large body of evidence demon- 
 strates the presence of disease in the nerve centre, attended by 
 proportionate injury to the sensory and motor system, and as a 
 consequence diminution of muscular strength. 
 
 Facts illustrating mental experience under a disordered cerebral 
 condition. — "We have now to pass over to a distinct class of 
 facts, associated with those just described, without which we 
 cannot have a clear view of the evidence bearing on the 
 relations of mind and brain. And here we must have some 
 regard to the absence of special mental experience connected 
 with recognised brain disorder, as well as the presence of an 
 abnormal experience which testifies to the existence of cerebral 
 disturbance. 
 
 Brain disease may exist to a large extent without experience of 
 uneasiness, or indications of mental restraint or aberration.— In 
 many cases of post-mortem examination a diseased condition of 
 brain has been found, where there had been no traces of mental 
 aberration during life. This fact is, indeed, often illustrated, 
 even during life, as has been shown (p. 205) in cases of para- 
 lysis, with unabated intellectual power. Brain disease may 
 assume a very serious form, without restraint on mental 
 activity. Dr. Ferrier says, " that not merely extensive lesions 
 in one hemisphere may be latent as regards mental symptoms, 
 but even a whole hemisphere may be disorganised with a like 
 negative result." 1 The division of the brain into two hemi- 
 spheres undoubtedly provides for a large amount of normal 
 activity both of mind and body, notwithstanding established 
 disease on one hemisphere. This holds true whether the dis- 
 order be on the right hemisphere or the left. The problem 
 thereby raised is a perplexing one for the theory which makes 
 the cerebrum itself the source of all mental action. Given 
 disorder of the brain, how is there not restraint upon mind? 
 It may be said by way of modifying the difficulty that such 
 disease may exist even without visibly restraining motor and 
 1 Localisation of Cerebral Disease, p. 6. 
 
XIII.] BRAIN DISORDERS. 385 
 
 sensory activity over the body. But if one hemisphere can 
 maintain the efficiency of motor and sensory nerves, this only 
 increases the difficulty by raising the question, Can a hemisphere 
 which is doing double work on the physical side, be at the 
 same time adequate for all that is accomplished by mind ? No 
 doubt account must here be made of the fact to which Dr. J. 
 Criehton Browne refers when he says, " It is astonishing how 
 little real thinking will suffice to carry a well-trained man 
 through an average day or month of an average life." 1 But 
 cases of congestion and of brain- wasting, along with acute and 
 powerful mental activity, have been numerous, and even noted 
 as having occurred in the history of some specially devoted to 
 abstruse reflection. 
 
 Even when Drain disease occasions delusions and mania, there 
 is abundant evidence of the power of accurate reasoning. — The 
 value of facts which may be classified under this division is 
 considerably affected by the locality of the lesion. The injury 
 to brain may be connected with sensory or motor centres, and 
 may but slightly affect those regarded as more immediately 
 concerned with intellectual action. Many examples must be 
 set aside on this account. There remain, however, cases of 
 delusion to which prominence must be given, as they indicate 
 serious disorder of brain. The sufferer under delusion reasons 
 accurately on the suppositions adopted by him to account 
 for his experience. No one would propose to deal argumen- 
 tatively with his case. His whole intellectual process is in 
 harmony with intellectual law as recognised and applied by 
 others; the delusion is a product of brain state, and can be 
 influenced or removed only by medical treatment. After the 
 delusion disappears, the reasoning process will proceed in ac- 
 knowledgment of the same intellectual laws as were recognised 
 during the period of delusion. 
 
 Evidence of a similar nature may be gathered even from 
 cases of brain-wasting, though here the observations become 
 more difficult, and the facts require more caution for their 
 interpretation. There can be no doubt, however, that intel- 
 lectual interest can be awakened and maintained when brain- 
 wasting is far advanced. For illustration I may refer to a case 
 
 1 British Medical Journal, 1871, vol. i. p. 442. 
 2 B 
 
386 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 which came under my observation when lecturing to more 
 than two hundred patients in our Edinburgh Asylum. In 
 giving some account of American scenery, the description of 
 Niagara was included, at the close of which I had the satisfac- 
 tion of being catechised by one of the patients, a gentleman 
 well known to me. The dialogue ran thus : — " How long is it, 
 sir, since you were in America ?" " About a year and a half." 
 " Oh, but I have been there since then." " Indeed I" " Yes, 
 sir, and the appearance of things is quite changed." " I was 
 not aware of that." " Well, sir, when I was out we drained 
 Niagara, and found in the rocks where the Falls were great 
 quantities of gold, which we had put into bars, and we are 
 coining it here just now." The difficulties of draining Lake 
 Erie were, of course, slight to the listener and thinker who sat 
 on the bench, but he saw clearly enough the engineering, 
 mining, smelting, and coining processes, and regarded them 
 with the interest of one who had given more thought to com- 
 mercial enterprise than to the beauties and grandeur of nature. 
 Shortly after the period here referred to, the patient had sunk 
 to a condition in which no such interest could be awakened, 
 and ere long was removed by death. 
 
 Strong Emotion may induce acute brain disorder. — In such 
 cases there is often a constitutional predisposition, either in 
 the sensitiveness of the nerve system, or in the weakness of 
 body at the time. But, on the other hand, the calamity is 
 often occasioned quite as much by the lack of self-govern- 
 ment, and a ruling influence which has been allowed to a 
 strong desire or passion. These two classes of influences are 
 so distinct as to involve actual contrast. In the former case 
 the body is weak, and the nerve system highly excitable. A 
 shock to the brain on account of the sudden loss of a cherished 
 relative may lead to mania, and that too in the history of one 
 distinguished for a high degree of reflective and self-governing 
 power. In the latter case the body is vigorous, but self-regu- 
 lation and quiet self-denial have been little cultivated. A 
 sudden reverse of fortune finds a body strong enough, but 
 a mind ill prepared for endurance of disaster. Bodily health 
 could be easily maintained if the person were allowed to go 
 about his usual avocations, and have his mind occupied 
 
xm.] BRAIN DISORDERS. 387 
 
 and stirred with fair prospects of success; but the bodily- 
 health gives way under the burden of a mind which_ sees the 
 fruit of a life-time of toil suddenly gone, and the life itself 
 change to dreariness. The contrast of the two sets of cases 
 is well known, and does not admit of interpretation under a 
 scheme of human life which traces all its experience to the 
 nerve centre. 
 
 Dr. Crichton Browne, when treating of brain-wasting, has 
 marked the contrast, and placed the power of human emotion 
 in an interesting light. He says : — " If mechanical pressure is 
 applied to a motor nerve in such a manner that, beginning 
 with the slightest contact, it is gradually and steadily in- 
 creased, even until the nerve is destroyed at the point of appli- 
 cation, no convulsions or spasms, but only deadness and 
 abolition of function are produced ; but, on the other hand, if 
 even a less degree of pressure is suddenly exerted, violent con- 
 vulsions and agitations inevitably ensue. Now, . . . moral or 
 mental pressure on the brain has two distinct sets of conse- 
 quences, according to the mode of its application, corresponding 
 with the two sets of consequences of mechanical pressure on a 
 motor nerve, to which we have referred. ... A sudden emo- 
 tion — a flash of joy or a pang of grief for which there had been 
 no preparation, and a hastily-imposed intellectual burden, — an 
 arduous task undertaken by an untrained mind, are most 
 likely to produce mania or some acute form of mental dis- 
 order ; a gradual emotion — pleasurable excitement ' long drawn 
 out,' or a canker care quietly eating its way, and a slowly im- 
 posed intellectual burden, the cumulative weight of a course 
 of study — are most likely to produce dementia or a progressive 
 impairment of the faculties." * 
 
 All treatment of the insane includes a moral element, as well 
 as a physical. — The physician does not content himself with 
 prescriptions and dietary arrangement, with air and exercise. 
 All these are quite essential to health, and their neglect would 
 be fatal. But the physician at the same time deals with the 
 mind by a perfectly distinct method of treatment. This is 
 universally recognised, and moral treatment is accordingly 
 adopted, whether the case be one in which the hope of re- 
 
 1 British Medical Journal, 1871, vol. i. p. 441. 
 
388 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 covery is great, or one in which liberation from the disorder can 
 come only through death. That such moral treatment is always 
 quite clearly denned and rigidly distinguished by the prac- 
 tised physician in his scientific expositions, it is hardly possible 
 to affirm. The physician is so habitually and necessarily occu- 
 pied with what are more properly a physician's problems, that, 
 as a rule, there is much clearer and fuller exposition of the 
 physical treatment than of moral — of the medicines to be 
 used, the diet to be assigned, the arrangement and ventilation 
 of apartments, the enforcing of cleanliness, and the provision 
 for open-air exercise. Advancing beyond this, there is full 
 recognition of the need for cheerfulness on the part of those 
 around, variety of occupation for the patients, amusements, and 
 every kind of soothing influence adapted to the special sensi- 
 bilities of the patients. But " moral treatment," properly so 
 called, is less clearly defined, and much more briefly de- 
 scribed. Nevertheless, it is constantly referred to, and that 
 in a manner which strongly supports this division of the pre- 
 sent argument. Thus Dr. Sankey introduces " moral treat- 
 ment of insanity " as "a very important part of the subject," x 
 and carefully and admirably discusses the old methods of re- 
 straint and repression, in contrast with the new methods of 
 non-restraint and encouragement. He says : — " By moral 
 ' treatment I mean that which is addressed to the patient's 
 mind ; in fact to the essential part of his disease. The whole 
 of the principle of this description of treatment is included in 
 one word — in the word Eest ; rest to the affected organ, that 
 is, the brain." 2 From the point of view occupied by those 
 who are distinctively analysts of mental experience properly 
 so called, the latter portion of this statement will seem incon- 
 sistent with the former. To speak of moral treatment as that 
 which is addressed to the patient's mind, and then to describe 
 it as Eest, seems to suggest a very slight address to the mind. 
 Aristotle found the key of moral life in the opposite word, 
 Energy (ivtpyeta) ; and certainly treatment which aims at 
 moral results can reach them only by activity, and that an 
 activity originating from the mind of the sufferer himself, on 
 account of a rational maxim of conduct which he accepts. To 
 ' Lectures on Mental Diseases, p. 217. 2 lb. 
 
xin.] BRAIN DISORDERS. 389 
 
 seek to promote personal control is an object of the physician 
 in his manifold efforts to secure the recovery of his patient, or 
 even a mitigation of the evils attending on chronic disease 
 of the brain. From what immediately follows in Dr. Sankey's 
 treatment of the subject, it appears that his mind was occu- 
 pied with an argument against the old method of resorting to 
 force, thus mastering the patient and bringing him to submis- 
 sion under the depressing conviction that struggle is hopeless. 
 All will sympathise with the author in his argument, and will 
 recognise how great a service has been done for humanity by 
 those who have strenuously contended against the reign of 
 force, happily now everywhere discredited and deplored. Very 
 naturally Dr. Sankey gives prominence to rest, as if that single 
 word were sufficient to indicate the character of the whole 
 system of treatment directly opposed to the plan of repression. 
 But, as soon as we pass beyond the dark shadow of the old 
 system, it becomes obvious that " moral treatment " must 
 signify a great deal more than the abandonment of the old, and 
 substitution of everything which contributes to quiet and per- 
 sonal calmness. There should be, and there really is, an effort 
 to carry the patient forward to a reflective exercise favourable 
 to the work of self-control. Just as some degree of self-control 
 begins to appear, is it possible for the physician to recognise 
 evidence of success in his Efforts by combination of physical 
 and moral treatment. This is the crowning result, towards 
 which rest can contribute only a proportion of the requisite 
 influence. As Dr. Sankey urges, the physician must "not 
 produce a bad mental effect on the patient ;" 1 but must accept 
 the system which " is wholly founded on its mental influence," 
 which " is directed to the pleasurable, and avoids all the de- 
 pressing emotions." 2 "The aim of the newer system is to 
 cheer, to conciliate the patient, to produce good feeling towards 
 his custodian ; to raise, not to depress him, to fill his mind with 
 the pleasurable emotions of hope, love, and thankfulness; to 
 inspire confidence, and which leads him to obey in order that 
 he may oblige, that he may obtain and retain the affection and 
 the friendship of those under whose care he is ; and this result 
 is not only attainable, but is almost universally achieved in 
 1 Lectures ore Mental Diseases, p. 225. 2 lb. p. 227. 
 
39° THE RELA TIONS OF MIND AND BRAIN. [chap. 
 
 English asylums." 1 This description of the aim of treatment, 
 valuable as it is, nevertheless shows too strongly the influence 
 of contrast with the old system ; and accordingly dwells almost 
 unduly on the agreeable, to the neglect of the self-restraint, and 
 therefore self-denial, which are essential to the moral life. The 
 results enumerated are all good and agreeable, but they lean 
 rather to the side of weakness, submission, and constant con- 
 trol by others. These are sought that the custodian may live 
 in the confidence of his patient, and this is something essential 
 for moral treatment. For it is no doubt true, as Dr. Sankey 
 maintains, that " the public profession or avowal of the system 
 of kindness and patience, and of the absence of all modes of 
 punishment, and of all means of confining the patient mechani- 
 cally, is of itself a moral remedy." 2 Kindness and patience 
 are prominent moral qualities, and when manifested by any 
 one in authority, are likely to encourage similar dispositions in 
 the person who is the object of them. But to awaken these as 
 they may be stirred in the mind of a child is not enough, since 
 all moral treatment must aim at a self-governed life, including 
 when needful quiet endurance of things disagreeable. This is 
 the ultimatum to which the physician's effort is directed, and 
 in the recognition and avowal of it, there is testimony that 
 appliances other than medical and those of domestic regimen 
 are to be employed. And this is testimony to the possibility 
 of a higher life, under higher government than that afforded 
 by nerve energy, which is upheld by suitable pabulum. This 
 becomes clear as Dr. Sankey carries forward his discussion. 
 He dwells upon these three features of treatment, — " Associa- 
 tion, employment, amusement, or diversion." 8 In treating first 
 of the patient's association with an attendant, it is well said in 
 regulations for the latter, that " a right feeling towards the 
 patient will usually indicate the proper conduct to be pursued." 
 As to employment, Dr. Sankey says, " The next general moral 
 remedy is Occupation ;" it is " second in importance only to 
 the treatment by Non-Eestraint," and is " its chief helpmate 
 still." 4 Not unnaturally it is added, with acknowledgment of the 
 great disadvantage involved, " among the insane of the upper 
 
 1 Lectures on Mental Diseases, p. 225. 
 
 * lb. p. 227. 3 lb, p. 235. ♦ lb. p. 240. 
 
xm.] BRAIN DISORDERS. 391 
 
 classes, the want of industrial employments is much felt." 
 Continuance at employment with an intelligent regard to what 
 is to he accomplished, is hut one of the lower forms of self- 
 regulated action, which must be established before the physi- 
 cian can have the satisfaction of reporting recovery. Mental 
 occupation will promote physical improvement; and an im- 
 proved physical condition will favour a freer and more inspirit- 
 ing action of intelligence. 
 
 In entire accordance with these views, is the argument on 
 the same subject by Dr. Maudsley. He says, " I cannot but 
 think that future progress in the improvement of the treatment 
 of the insane lies in the direction of lessening the sequestra- 
 tion, and increasing the liberty of them." 1 And still more 
 directly, " The patient having been removed from those influ- 
 ences which have conspired to the production of the disease, 
 and now tend to keep it up, and having been made to recognise 
 from without a control which he cannot exercise from within, 
 it remains to strive patiently and persistently by every induce- 
 ment to arouse him from his self-brooding or self-exaltation, 
 and to engage his attention in matters external — to make him 
 step out of himself. This is best done by interesting him in 
 some occupation, or in a variety of amusements. Steady 
 employment will do more than anything else in promoting 
 recovery ; with the insane, as with the sane, action is the best 
 cure for suffering. The activity of the morbid thoughts and 
 feelings subsiding in new relations and under new impressions, 
 more healthy feelings may be gradually awakened; and the 
 activity of healthy thought and feeling will not fail in its turn 
 further to favour the "decay of morbid feeling." 2 
 
 These quotations shew how decidedly those most conversant 
 with the practical requirements for medical supervision of 
 disease of the brain, recognise the necessity for " moral treat- 
 ment," having for its aim to promote a return to self-control, 
 and a mastery over morbid tendencies. Such testimony is the 
 acknowledgment that personal effort is needful to secure 
 victory over the morbid feelings which the disordered condition 
 of the organism favours. Such references to moral considera- 
 
 1 Physiology and Pathology of Mind, Second Edition, p. 501. 
 
 2 lb. p. 507. 
 
392 THE RELA TIONS OF MIND AND BRAIN. [chap. 
 
 tions proclaim, that organism even though disordered is con- 
 trolled by a power higher than itself. 
 
 It is desirable here to refer to certain phenomena connected 
 with moral life, which may be regarded as introducing some per- 
 plexity. I allude to the moral perversion which often occurs 
 in the case of the insane. If a person who has led a wicked 
 life is found to give evidence of his wickedness when placed 
 under restraint, there is no marvel. But, under an attack of 
 insanity, a complete reversal of conduct often occurs in the history 
 of those who had previously led an exemplary and even noble 
 life. It thus appears as if moral excellence depended upon the 
 healthy condition of the brain. The evidence in proof of such 
 " moral perversion " is abundant and beyond dispute. The in- 
 terpretation of it is the matter which demands consideration. 
 The breach of continuity which such " perversion " involves is 
 the main feature here requiring attention. The building up of 
 moral character is not a thing of a day. The lessons of self- 
 restraint, endurance, and perseverance recur day by day, and 
 are hard to learn. Through manifold struggles, at times re- 
 warded with success, often ending in failure, progress had been 
 made, till the man has attained to a measure of decision of 
 character. By silent ponderings, issuing in fresh resolves, and 
 leading out to new efforts, the lower nature is brought into 
 subjection, while the strength, mellowness, and consistency of 
 true moral life begin to appear. But a period of physical 
 weakness comes, great nervous sensibility sets in, and just when 
 strength is low, a sudden shock is encountered, under which 
 decided disorder of brain is developed. Then it seems as if 
 the benevolence, self-denial, and purity so much admired 
 had evaporated, and a self-indulgent, ill-regulated life stands 
 in melancholy contrast with the nobler conduct which was 
 previously characteristic. Shall we say that moral character 
 can melt away like snow before the breath of spring ? Has 
 the law of continuity so slight application in human life as 
 to admit of a complete reversal with change of health ? Or 
 shall we say that the change in physical condition which has 
 induced the brain disorder has imposed a physical barrier 
 to the action of mind, and yet has left in operation all the 
 functions of merely animal life ? That the latter is the true 
 
xm.] BRAIN DISORDERS. 393 
 
 state of the case seems evident from such an illustration as that 
 afforded by the condition of brain which stands last in the 
 series described (p. 378), where brain-wasting was widely ex- 
 tended, and the blood-vessels were hard and thick as quills. If 
 there is continuity and not reversal in the life of the profligate, 
 the fact is only confirmatory of the view here taken, that the 
 animal tendencies can operate where mental government is 
 restrained. If there is a " moral perversion " in the case of 
 those distinguished for self-regulation when in a healthy state, 
 the so-called " perversion," appearing in the activity of animal 
 propensities, and the non- activity of moral forces, is in reality 
 a testimony to the superiority of mind over matter in all the 
 earlier history, and is not in any way an argument for the 
 dependence of moral character on nerve energy. 
 
 III. Violent injury to the healthy brain. 
 
 Additional light is thrown on the relations of mind and brain 
 by a considerable body of evidence accumulated in connection 
 with accidental injury to the nerve centre. The head, though 
 strongly protected by the cranium, does not escape its share of 
 injuries, and when the skull is fractured, there is even addi- 
 tional risk on account of pieces of bone being driven in upon 
 the brain tissue. In this way, serious falls, gunshot wounds, 
 and injuries by machinery, have all contributed something to 
 our study of brain action, under pathological conditions. A 
 few examples, selected with some regard to diversity of pheno- 
 mena, will afford illustration of the supplementary body of 
 evidence here accumulated. In this way we can see epileptic 
 experience and loss of self-control caused by a single instan- 
 taneous breach of the normal condition and relations of the 
 brain. A physical injury makes palpable to the eye of the 
 pathologist a condition which is more commonly recognised 
 by the gradual advance of hidden disease. The locality and 
 exact form of injury also adds considerably to the knowledge 
 we have of the functions of different portions or lobes of the 
 brain. 
 
 The following case, recorded by Professor Nothnagel of Jena, 
 illustrates accidental injury resulting in epilepsy: — " A boy of 
 eight years, who came of a perfectly healthy family, had never 
 been seriously ill, and had had no convulsions in teething, fell 
 
394 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 a distance of twelve feet upon hard ground, striking on the 
 head. He lay unconscious for some fifteen minutes, after 
 which he roused, and at the end of ten minutes more was 
 seized with a marked epileptic attack. There was a small 
 scalp-wound on the right side of the head which healed in a 
 few days. After that, for six weeks, he was in a condition of 
 perfect health ; then there was again an epileptic seizure, and 
 from that time they have constantly recurred, in former years 
 at considerable intervals, of late years every four to twelve days. 
 They always occur without an aura (sensation as of a stream of 
 air), being but very seldom preceded by a momentary dizziness. 
 They invariably begin by a turning of the head to the left ; con- 
 sciousness is then first lost, the countenance becoming pale at 
 the same time, and general convulsions declare themselves. 
 Interparoxysmal symptoms exist to a limited degree ; from 
 time to time only a little headache ; and sometimes there 
 appear slight twitchings in the left half of the face or in the 
 left arm. The patient, who is now a vigorous person of 
 twenty-one years, appears to be of rather limited mental 
 powers, and complains of a weak memory. Objectively there 
 is nothing to be discovered except a cicatrix, about the size of 
 a lentil, corresponding to the right coronal suture, and four 
 centimetres distant from the medial line. This is not painful 
 or adherent, and when touched, either gently or quite roughly, 
 no symptoms are manifested, no epileptogenous zone is to be 
 found." 1 Under such conditions as those described, it is cer- 
 tain that there must be lifelong restraint upon the action of 
 mind, if we judge of its action by the power of concentrated 
 attention. And when it is said that the patient " complains of 
 weakness of memory," this harmonises with what has been 
 already shown as to the large degree in which memory depends 
 on brain action. 
 
 In view of the importance commonly assigned to the anterior 
 lobes of the brain, special interest naturally concentrates on 
 injuries to the frontal regions. On this account it is desirable 
 to select illustrations bearing to some extent on the functions 
 of this portion of the nerve centre. 
 
 In connection with his investigations as to the centre for 
 1 Zicmsscu'a Cyclopedia of the Practice of Medicine (transl.), vol. xiv. p. 208. 
 
xin.] BRAIN DISORDERS. 395 
 
 speech, Dr. Bateman has transcribed a case of interest in this 
 relation. " In Trousseau's Clinique MMicale the following case 
 is recorded : — In the year 1825, two officers quartered at Tours 
 quarrelled, and satisfied their honour by a duel, as a result of 
 which one of them received a ball which entered at one 
 temple, and made its exit at the other. The patient survived 
 six months without any sign of paralysis or of lesion of arti- 
 culation, nor was there the least hesitation in the expression 
 of his thoughts, till the supervention of inflammation of the 
 central substance, which occurred shortly before his death, 
 when it was ascertained that the ball had traversed the two 
 frontal lobes at their centre." 1 The two negative results, absence 
 of paralysis, and non-disturbance in the expression of thought, 
 are of undoubted importance in the interpretation of brain 
 functions. 
 
 The most striking case in this relation is that which is now 
 widely known as " the American Crowbar Case." The facts 
 were first described by Dr. Bigelow, 2 and the subsequent his- 
 tory of the sufferer was detailed by Dr. Harlow, in a paper 
 read before the Massachusetts Medical Society, June 3, 1868. 
 Dr. Ferrier has given considerable attention to the case, pre- 
 senting a drawing of the skull as it is now preserved in the 
 Medical Museum of Harvard University, Massachusetts, and 
 from him I take the account of the case, along with his critical 
 remarks on the mental activity of the man subsequent to the 
 accident. 
 
 "The subject of the lesion was a young man, Phineas P. 
 Gage, aged twenty-five. While he was engaged tamping a 
 blasting charge in a rock with a pointed iron bar, 3 feet 7 
 inches in length, 1£ inches in diameter, and weighing 13J lbs., 
 the charge suddenly exploded. The iron bar, propelled with 
 its pointed end first, entered at the left angle of the patient's 
 jaw, and passed clean through the top of his head, near the 
 sagittal suture in the frontal region, and was picked up at some 
 distance covered with 'blood and brains.' The patient was 
 for a moment stunned, but, within an hour after the accident, 
 he was able to walk up a long flight of stairs and give the 
 
 1 Bateman's Aphasia, p. 19. 
 
 2 American Journal for Medical Sciences, July 1850. 
 
396 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 surgeon an intelligible account of the injury he had sustained. 
 His life was naturally for a long time despaired of; but he 
 ultimately recovered, and lived twelve and a half years after- 
 wards. Unfortunately, he died (of epileptic convulsions) at a 
 distance from medical supervision, and no post-mortem examin- 
 ation of the brain was made ; but, through the exertions of Dr. 
 Harlow, the skull was exhumed and preserved. Upon this 
 the exact seat of the lesion can be determined. The line of 
 union of the cicatrices of entrance and exit, however, allowed 
 a pretty accurate estimation of the track of the bar during 
 life, and Dr. Bigelow did so with considerable accuracy. Dr. 
 Bigelow, who examined the man two years after the accident, 
 thus describes the appearances presented : — ' A linear cicatrix 
 of an inch in length occupies the left ramus of the jaw near 
 its angle. ... The eyelid of this side is shut, and the patient 
 unable to open it ; the eye considerably more prominent than 
 the other. [Vision lost (Harlow).] . . . Upon the head, and 
 covered by the hair, is a large unequal depression and eleva- 
 tion. ... A piece of the cranium of about the size of the palm 
 of the hand, its posterior border lying near the coronal suture, 
 its anterior edge low on the forehead, was raised upon the latter 
 as a hinge, to allow the egress of the bar ; still remains raised 
 and prominent. 
 
 " From his examination of the skull itself, Dr. Harlow thus 
 describes the track of the bar : — ' The missile entered, as pre- 
 viously stated, immediately anterior and external to the angle 
 of the inferior maxillary bone, proceeding obliquely upwards 
 in the line of its axis, passed under the junction of the superior 
 maxillary and malar bones, comminuting the posterior wall of 
 the antrum, entered the base of the skull at a point the centre 
 of which is an inch and a quarter to the left of the median line, 
 in the junction of the lesser wing of the sphenoid with the 
 orbitar process of the frontal bone — comminuting and remov- 
 ing the entire lesser wing with one half of the greater wing of 
 the sphenoid bone— also fracturing and carrying away a large 
 portion of the orbitar process of the frontal bone, leaving an 
 opening in the base of the cranium, after the natural efforts at 
 repair by the deposit of new bone, of one inch in its lateral, by 
 two inches in its antero-posterior, diameters.' (Op. cit. p. 17.) 
 
xiit.] BRAIN DISORDERS. 397 
 
 Dr. Harlow does not describe the further track of the bar through 
 the frontal bone, but you will clearly see, from the figures, that 
 the whole lesion is situated anterior to the coronal suture. If, 
 now, you will compare the track of the bar through the skull 
 and brain with the diagram before you (fig. 3) showing the 
 relations between the skull and the brain, you will, I think, 
 have no doubt in convincing yourselves that the whole track is 
 included within that region of the brain which I have described 
 as the prae-frontal region, and that, therefore, the absence of 
 paralysis in this case is quite in harmony with the results 
 of experimental physiology. The only other region which the 
 bar could have injured is the tip of the temporo-sphenoidal 
 lobe and the outer roof of the olfactory bulb. Respecting the 
 condition as to smell, nothing is, however, said by either 
 Bigelow or Harlow. This case is generally quoted as one in 
 which the man suffered no damage bodily or mental. But 
 hear what Dr. Harlow says as to his mental condition. ' His 
 contractors, who regarded him as the most efficient and capable 
 foreman in their employ previous to his injury, considered the 
 change in his mind so marked that they could not give him his 
 place again. The equilibrium or balance, so to speak, between 
 his intellectual faculties and animal propensities seems to have 
 been destroyed. He is fitful, irreverent, indulging at times in 
 the grossest profanity (which was not previously his custom), 
 manifesting but little deference for his fellows, impatient of 
 restraint or advice when it conflicts with his desires, at times 
 pertinaciously obstinate, yet capricious and vacillating, devis- 
 ing many plans of future operation, which are no sooner 
 arranged than they are abandoned in turn for others appear- 
 ing more feasible. A child in his intellectual capacity and 
 manifestations, he has the animal passions of a strong man. 
 Previous to his injury, though untrained in the schools, he pos- 
 sessed a well-balanced mind, and was looked upon by those 
 who knew him as a shrewd, smart business man, very ener- 
 getic and persistent in executing all his plans of operation. In 
 this regard his mind was radically changed, so decidedly, that 
 his friends and acquaintances said he was " no longer Gage." ' 
 (Op. cit. p. 18.) 
 
 " After these facts, I do not think it can be said with justice 
 
398 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 that the man suffered no damage either bodily or mentally, 
 or that the ' American Crowbar Case ' is in opposition to the 
 experimental facts which I have adduced as to the effect of 
 lesions of the frontal lobes." 1 
 
 The most important facts in the experience of Gage bearing 
 directly on the present inquiry are these ; — that an hour after 
 the accident he was able to give an intelligible account of the 
 injury he had sustained; that he showed in after-life want of 
 self-control ; that this appeared in a predominance of animal 
 propensities, fitfulness as to personal purpose, impatience, 
 excitability, and stubbornness when interfered with ; but there 
 was no failure in power to hold intelligent communication 
 with others. The whole account indicates want of governing 
 power ; but it does not show such interference with intelligent 
 action as to make the man incapable of appreciating distinc- 
 tions, or accurately describing events. His companions rightly 
 estimated the situation when they said he was " no longer 
 Gage," meaning that he was no longer capable of attempting 
 the work he could once do, or of directing others as he had 
 done before. But the whole bearing of the case is misunder- 
 stood if the testimony of his possessing " a well-balanced mind" 
 before the accident, is interpreted as meaning anything more 
 than well-directed effort in the performance of the work of a 
 quarryman. He was not a man of even average education, 
 much less of any intellectual power. The failure in self- 
 government which appeared might, indeed, readily enough be 
 described as " moral perversion," and yet it would be most 
 erroneously described under such a designation. If anything 
 be obvious it is this, — that as Gage was not responsible for the 
 accident which befell him, so neither was he responsible for 
 the difficulty in controlling himself which he experienced. 
 Eut it does not therefore follow that it was not his duty to 
 begin an entirely new effort at self-control, required in his 
 altered circumstances. His greater difficulties entitled him to 
 greater consideration, but did not terminate his obligations. 
 It is obvious that the man had a continual sense of uneasi- 
 ness ; that he had a painful consciousness of inability to work 
 as he had done ; that he was " impatient of restraint or advice 
 
 1 Localisation of Cerebral Dhease, pp. 28-30. 
 
xni.] BRAIN DISORDERS. 399 
 
 when it conflicted with his own desires," such " restraint or 
 advice " involving an addition to the burden of " restraint " 
 which already tried his spirit. These two last-named facts 
 imply a mind disturbed, yet dealing with the difficulties of his 
 painful situation. His impatience of restraint and advice are 
 to be accounted for partly by uneasiness, partly by an intelli- 
 gent effort to regulate physical action under the distraction 
 which the uneasiness occasioned. His impatience discovers 
 more than physical uneasiness. He was impatient of advice. 
 This was clearly the irritation of a reflective nature, disturbed 
 by the uneasiness of the physical nature, and aggravated by 
 counsels which do not help, but hinder the mind in its 
 endeavours. There is no possibility of making an intelligible 
 harmony of the narrative except on this clear admission. The 
 speciality of the case is the illustration it affords of a person con- 
 tending throughout thirteen years with extraordinary disturb- 
 ance of functional activity in the nerve centre, and continuing 
 to show accurate intelligence, along with inadequate power of 
 control. How serious the physical disturbance had been, 
 became apparent at length in the fact that the sufferer " died of 
 epileptic convulsions." The result of his physical state must 
 have been irritability, liable to be excited by conflicting advice. 
 Dr. Terrier has said, " I might multiply instances all demon- 
 strating the same fact, that sudden and extensive lacerations 
 may be made in the prae-frontal region, and large portions of 
 the brain-substance may be lost, without causing impairment 
 either of sensation or of motion; and, indeed, without very 
 evident disturbance of any kind, bodily or mental, especially if 
 the lesion be unilateral." 1 These words may require some 
 modification if applied to the experience of Gage; but the 
 case affords a striking illustration of Dr. Ferrier's statement. 
 Additional importance attaches to its bearing on the functions 
 of the frontal lobes, with which the intellectual and governing 
 powers of human life are commonly associated. A breach of 
 the controlling power resulted from the injury to the frontal 
 region; but there is evidence of comparatively little inroad 
 on the intelligence proper. In this connection it is desirable 
 also to keep in view the fact that the activity of the intel- 
 1 Localisation of Cerebral Disease, \>. 33. 
 
400 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 lectual powers has been associated with the posterior region in 
 the brain. On this point Dr. Bastian presents his testimony 
 in the following form : — " Various reasons led me some years 
 ago to the conclusion that the posterior lobes of the brain had 
 more to do with higher intellectual functions than the anterior 
 lobes — a conclusion which, however contrary it may be to 
 generally received opinions, has since been strengthened by 
 observations made independently in different directions and by 
 different persons. It seems to agree, moreover, with clinical 
 and pathological evidence. Dr. Hughlings Jackson and other 
 authorities on the subject of brain disease agree with me in 
 thinking that mental impairment or derangement is apt to be 
 more especially marked where we have to do with injuries of 
 the posterior lobe of the brain — that is, such signs are prone to 
 be more marked than with lesions of the anterior lobe of the 
 brain, notwithstanding the popular notion as to the decidedly 
 greater importance of this part in respect to intellectual func- 
 tions." 1 In so far as one may judge from premonitory symptoms 
 resulting from overwork, I can testify from repeated experience 
 that uneasiness is first experienced in the frontal region ; at a 
 stage in advance of this, an uneasy feeling sweeps at times over 
 the upper region from front to rear; and at a third stage, 
 this is followed by a stroke or sudden shock in the posterior 
 region. Whether this implies that superior activity belongs to 
 the posterior lobes, or that the organ acts in some sense as a 
 whole, while the governing power belongs to the frontal region, 
 I should not venture to conclude. 
 
 There is still another possibility, as the result of accidental 
 injury, which deserves passing attention, — I mean the loss of a 
 portion of brain substance not only without detriment, but 
 with perceptible advantage to the performance of brain func- 
 tions. Examples of this must be of rare occurrence, as are 
 examples of microcephaly. The relation of the mass of brain to 
 the cavity of the skull in which it is stored is so suitable, that 
 there is in the normal condition an exact adaptation. In the 
 history of disease, however, such facts as these are familiar, that 
 the formation of a tumour on the brain, and consequent pres- 
 sure on a portion of the substance of the brain, may interrupt 
 
 1 Paralysis from Brain Disease, p. 239. 
 
xnr.] BRAIN DISORDERS, 401 
 
 functional activity of the underlying part, and also that accu- 
 mulation of fluid may not only greatly distend the cranium, but 
 impede the action of the cerebrum. Apart from such forms of 
 disease, however, there may be cases of megalocephaly, in 
 contrast with those of microcephaly. It is possible that brain 
 development may so far exceed the natural capacity of the 
 cranium, as to cause the grey matter to press considerably 
 against the hard walls of the cavity, inducing compression of 
 the organ as a whole. Dr. James Sidey of Edinburgh, the 
 surgeon who attended the patient, has favoured me with the 
 particulars of a case which deserves to be recorded : — " A 
 navvy, while working at the formation of the Leeds and 
 Thirsk Eailway, was struck by a revolving crane handle on 
 the upper part of the left parietal bone, producing a com- 
 pound comminuted fracture, with {hernia cerebri) protrusion 
 of the brain as large as a bantam's egg. After admission to 
 the Hospital, the case did well, about ten or twelve small 
 pieces of bone were removed — the protruding brain sloughed 
 off, the wound healed over, and the man was discharged 
 about six weeks after admission, without having shown 
 any bad symptoms or taken one single dose of medicine 
 during his stay there. Previous to admission he was misan- 
 thropic, lived in a hut alone, washed his own clothes, 
 cooked his own food, and seemed peculiar in many ways. 
 A month after he was dismissed from Hospital he married, 
 and ever afterwards conducted himself as a most respectable 
 member of society, showing none of his former peculiarities." 
 This case may be regarded as in some respects a companion 
 with the " American Crowbar Case." But the improvement 
 on the sufferer is a speciality. Mental activity being an 
 exercise in many respects superior to brain action, his appre- 
 ciation of kindly nursing may have had a good deal to do 
 with the cure of misanthropy, as well as the cure of the 
 broken head. But the fact deserves notice, that improve- 
 ment in disposition and conduct followed upon a loss of 
 brain, which does not seem to have been in any degree detri- 
 mental. 
 
 In closing these investigations as to brain disorder, it is 
 desirable briefly to consider the relation of personal power to 
 
 2 c 
 
402 THE RELA TIONS OF MIND AND BRAIN. [chap. 
 
 the tendencies which induce insanity, and to those influences 
 which avert the action of such tendencies. 
 
 1. Personal conduct may induce insanity. 
 
 Apart altogether from questions of heredity, it is clear that 
 certain courses of action tend to induce insanity. The laws of 
 health apply as rigidly for brain as for lungs, heart, and liver. 
 We have seen that immorality, whether in the form of drunk- 
 enness or licentiousness, predisposes to insanity. At the other 
 extreme, overwork of brain, taxing its energy by the number of 
 hours devoted to study or mental work of other kinds, may 
 induce exhaustion and active disease, thereby hindering the 
 ordinary exercise of self-control. Just as truly as the lower 
 and most debasing forms of immorality are to be shunned, so 
 are also the excessive efforts of industry and concentrated 
 thought, which, by their breach of the laws of health, involve 
 in their own way a phase of immorality. There are symptoms 
 which warn us clearly enough of overworking of brain, and which 
 we are under obligation to treat as warnings of danger. Per- 
 sonal purpose may exact more than the physical organ can 
 endure, an obvious token of the superiority of mind to brain. 
 On the other hand, personal observation may mark the symptoms 
 of danger, and personal determination may avert the conse- 
 quences which would otherwise follow, — another fact which 
 contributes its complement of evidence to the superintendency 
 which the intelligence wields over brain. An additional form 
 in which, as previously remarked, we are exposed to danger is 
 that arising from the sudden shocks to which our life is liable. 
 Sudden and great calamity, — or a succession of disasters of any 
 kind coming rapidly in personal history,— involves a risk, 
 greater or less, according partly to the condition of health in 
 which the trial finds us, and partly to the degree in which we 
 have trained ourselves to endure suffering and sorrow. The 
 hazard from such calamities is in some sense greater, because 
 we cannot guard against their occurrence, and cannot take 
 measures to secure that when they do break upon us, it shall 
 not be when we are in an enfeebled condition. In personal 
 and domestic history, such trial must often find us in a physical 
 condition ill prepared for endurance. Our single defence in 
 such circumstances is that which is supplied by a sound moral 
 
xili.] BRAIN DISORDERS. 403 
 
 training in the needful work of endurance, directed by true 
 views of the secondary value of material possessions, of the 
 superior value of human nature, and the grandeur of its 
 destiny, in harmony with the government of an absolute Moral 
 Euler of the universe. 
 
 Apart from such natural calamities as those to which all are 
 liable, it must be added that special risks attend upon the con- 
 tinuance and encouragement of abnormal excitement of brain. 
 The life of De Quincey is full of instruction in this respect. 1 
 Under the same category come all cases in which an unnatural 
 excitement is kept up during sleep, whether that be natural 
 slumber, or artificially induced, as in the case of "mesmeric 
 sleep." Among the cases preserved for us by Dr. Abercrombie, 
 there is one which deserves special notice as illustrating what 
 is here under consideration: — "A girl aged seven years, an 
 orphan of the lowest rank, residing in the house of a farmer, 
 by whom she was employed in tending cattle, was accustomed 
 to sleep in an apartment separated by a very thin partition 
 from one which was frequently occupied by an itinerant 
 fiddler. This person was a musician of very considerable skill, 
 and often spent a part of the night in performing pieces of a 
 refined description ; but his performance was not taken notice 
 of by the child except as a disagreeable noise. After a resi- 
 dence of six months in this family she fell into bad health, and 
 was removed to the house of a benevolent lady, where, on her 
 recovery after a protracted illness, she was employed as a 
 servant. Some years after she came to reside with this lady, 
 the most beautiful music was often heard in the house during 
 the night, which excited no small interest and wonder in the 
 family ; and many a waking hour was spent in endeavours to 
 discover the invisible minstrel. At length the sound was 
 traced to the sleeping-room of the girl, who was found fast 
 asleep, but uttering from her lips a sound exactly resembling 
 the sweetest tones of a small violin. On further observation it 
 was found that, after being about two hours in bed, she became 
 restless and began to mutter to herself ; she then uttered sounds 
 precisely resembling the tuning of a violin, and at length, 
 after some prelude, dashed off into elaborate pieces of music, 
 1 Confetsiwis of an Opium Eater. 
 
404 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 which she performed in a clear and accurate manner, and with 
 a sound exactly resembling the most delicate modulations of 
 that instrument. During the performance she sometimes 
 stopped, made the sound of retuning her instrument, and then 
 began exactly where she had stopped, in the most correct 
 manner. These paroxysms occurred at irregular intervals, 
 varying from one to fourteen or even twenty nights ; and they 
 were generally followed by a degree of fever, and pains over 
 various parts of her body. 
 
 " After a year or two, her music was not confined to the imi- 
 tation of the violin, but was often exchanged for that of a 
 piano of a very old description which she was accustomed to 
 hear in the house where she now lived; and she then also 
 began to sing, imitating exactly the voices of several ladies of 
 the family. In another year from this time she began to talk 
 a great deal in her sleep, in which she seemed to fancy herself 
 instructing a younger companion. She often descanted with 
 the utmost fluency and correctness on a variety of topics, both 
 political and religious, the news of the day, the historical parts 
 of Scripture, public characters, and particularly the characters 
 of members of the family and their visitors. In these discus- 
 sions she showed the most wonderful discrimination, often 
 combined with sarcasm, and astonishing powers of mimicry. 
 Her language through the whole was fluent and correct, and 
 her illustrations often forcible, and even eloquent. She was 
 fond of illustrating her subjects by what she called a, fable, and 
 in these her imagery was both appropriate and elegant. ' She 
 was by no means/ says my informer, ' limited in her range — 
 Buonaparte, Wellington, Bliicher, and all the kings of the earth, 
 figured among the phantasmagoria of her brain ; and all were 
 animadverted upon with such freedom from restraint, as often 
 made me think poor Nancy had been transported into Madame 
 de GenUs' Palace of Truth. The justness and truth of her re- 
 marks on all subjects excited the utmost astonishment in those 
 who were acquainted with her limited means of acquiring in- 
 formation.' She has been known to conjugate correctly Latin 
 verbs which she had probably heard in the school-room of the 
 family; and she was once heard to speak several sentences 
 very correctly in French— at the same time stating that she 
 
xiii.] BRAIN DISORDERS. 405 
 
 heard them from a foreign gentleman whom she had met acci- 
 dentally in a shop. Being questioned on this subject when 
 awake, she remembered having seen the gentleman, but could 
 not repeat a word of what he said. During her paroxysms it 
 was almost impossible to awake her, and when her eye-lids 
 were raised, and a candle brought near the eye, the pupil 
 seemed insensible to the light. For several years she was, 
 during the paroxysms, entirely unconscious of the presence of 
 other persons; but, about the age of sixteen, she began to 
 observe those who were in the apartment, and she could tell 
 correctly their numbers, though the utmost care was taken to 
 have the room darkened. She now also became capable of 
 answering questions that were put to her, and of noticing 
 remarks made in her presence ; and, with regard to both, she 
 showed astonishing acuteness. Her observations indeed were 
 often of such a nature, and corresponded so accurately with 
 characters and events, that, by the country people, she was 
 believed to be endowed with supernatural powers. 
 
 " During the whole period of this remarkable affection, which 
 seems to have gone on for at least ten or eleven years, she was, 
 when awake, a dull, awkward girl, very slow in receiving any 
 kind of instruction, though much care was bestowed upon her ; 
 and, in point of intellect, she was much inferior to the other 
 servants of the family. In particular she showed no kind of 
 turn for music. She did not appear to have any recollection 
 of what passed during her sleep; but, during her nocturnal, 
 rambling, she was more than once heard to lament her in- 
 firmity of speaking in her sleep, adding how fortunate it was 
 that she did not sleep among the other servants, as they teased 
 her enough, about it as it was. About the age of twenty-one 
 she became immoral in her conduct, and was dismissed from 
 the family. Her propensity to talk in her sleep continued to 
 the time of her dismissal, but a great change had taken place 
 in her nocturnal conversation. It had gradually lost its acute- 
 ness and brilliancy, and latterly became the mere babblings of 
 a vulgar mind, often mingled with insolent remarks against 
 her superiors, and the most profane scoffing at morality and 
 religion. It is believed that she afterwards became insane." 1 
 
 1 Abercrombie's Intellectual Powers, 12th edition, pp. 245-248. 
 
406 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 This case illustrates in a singular way how brain excitement 
 may be induced, and how by persistent subjection to such 
 excitement during the hours of sleep, a physical condition is 
 brought about which tends towards insanity. The significance 
 of the facts may be seen if we note the successive stages in 
 the history of the case. The girl was only seven years of 
 age when disturbed by the playing of the violin. Her sleep 
 was not broken by this, but her brain was kept in an ex- 
 cited condition, and that at a period in life when such 
 excitement is apt to have a most disturbing and persistent 
 effect (p. 353). She was a girl who had no educational advan- 
 tages, and few of the attentions which the home circle supplies ; 
 — " an orphan of the lowest rank," tending cattle, and appar- 
 ently having her sleeping quarters in a barn or hay -loft, for 
 that has been the common place in the farm houses of Scotland 
 for spreading a bed for wandering minstrels. After six months 
 she passed through a severe illness in which brain excitability 
 is likely to have been increased. In the new and more favour- 
 able sphere of service to which she was transferred, the sensi- 
 tiveness to sounds was acted upon afresh by musical perform- 
 ances strange to her. There it was discovered that about two 
 hours after she had gone to bed, — probably the time about 
 which the itinerant violinist began to tune his instrument, — 
 "she became restless." Then she "began to mutter to her- 
 self." This appears to have been a repetition of the natural 
 complaint she made on account of disturbance of sleep. Next, 
 she began her imitations of the music she had heard. This 
 was the reflex action of the brain, reproducing the cause of 
 excitement, and thereby intensifying (p. 55) the excitability. 
 The physical result of disturbed sleep and excited brain was 
 " a degree of fever, and pains over various parts of her body," 
 the fever being a natural consequence, and the pains being 
 probably induced by muscular activity connected with the 
 imitation of actions quite unusual to her. Next came evidence 
 of having experienced extended impressions from musical 
 effects, leading to imitations of the piano. Thus an abnormal 
 excitability to the influence of sound was being established. 
 And nothing was done to break the tendency. Unfortunately 
 everything seems to have been done to stimulate it. The 
 
xm.] BRAIN DISORDERS. 4°7 
 
 performances of the girl became matter of curiosity. People 
 gathered together in- her sleeping chamber to listen and to 
 watch, — not to break the spell, and set the poor child free, 
 — their whisperings and merriment added to the unnatural 
 excitement of the nerve system, and tended to aggravate it. 
 Then at length — nine years after the first manifestation of 
 restlessness in sleep — her attention was called into activity 
 to interpret what was spoken to her, and reply to her 
 questioners. Sensitiveness of brain was thus acted upon in 
 new ways. Singular sounds, such as the words of a foreign 
 language, or explanations of things not understood, produced 
 a vivid impression on a brain excitable to an unnatural 
 degree. To the musical performances of the night were 
 now added recitations, conjugations of verbs, and repetitions 
 of historical narrative. A more effectual means of utterly 
 ruining a nerve system could hardly be devised, and as a 
 certain result the power of personal control was being sacri- 
 ficed. Nothing seems to have been done to direct her own 
 attention on the malady to which she was subject, or to 
 encourage her in an effort to break the spell and end the 
 dominion which had become established. There was teasing 
 enough by day, as well as brain excitement by night ; but a 
 want of requisite help to break the pernicious habit. If 
 only an effort had been made in the direction which Dr. 
 Thomas Eeid describes (p. 341) as having been successfully 
 made in his own case at the age of fourteen, she might have 
 been saved from life- long injury. " About the age of twenty- 
 one she became immoral." The animal nature, excited and 
 ungoverned, was under no control of the intelligent nature, and 
 the history of her domestic service is ended by saying, that she 
 was " dismissed from the family ;" the life record is closed by 
 saying — " It is believed she afterwards became insane." There 
 is little demand upon belief in such a case ; she was insane 
 before she was dismissed, and this " immorality " was after the 
 type of " moral perversion " found among the insane, and which 
 with no show of reason can be described as " immorality," but 
 only as " insanity," — a disordered brain and an excited physical 
 condition. 
 
 The case affords a striking illustration both of the power and 
 
408 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 the weakness of brain. A summary of its contribution to the 
 evidence concerning the relations of mind and brain is desirable. 
 We have a series of abnormal manifestations of brain activity 
 consequent on disturbed sleep, inducing chronic excitement of 
 the organ. This excitement is connected with the condition of 
 sleep, and does not appear when the patient is awake. During 
 the paroxysm the condition of brain differs so much from that 
 of ordinary sleep, that it is " almost impossible to awake her." 
 There are here two distinct orders of facts, the one bearing on 
 the abnormal activity of brain, the other on ordinary mental 
 activity during the abnormal excitement. (1.) There is imi- 
 tation, without intelligent appreciation. There is wonderful 
 musical imitation — a singular example of brain activity oper- 
 ating upon the vocal organs in a way which could not be easily 
 executed by an accomplished musician in his waking hours. 
 Indeed we may say that the more accomplished the musician 
 the more difficult would prove the attempt „to reproduce the 
 effects produced with facility by this illiterate girl during the 
 paroxysm of brain excitement. Her imitation is mechanical, 
 and this so completely that she imitates the " tuning " of the 
 violin, and even stops for " retuning," as no person attempting 
 vocal imitation of the violin would dream of doing. In accord- 
 ance with the purely mechanical nature of the action during 
 a period of abnormal brain excitement, the girl never thought 
 of attempting the exercise during her waking hours. Thought 
 played no part in the production of the effects. (2.) There is 
 some intelligent action accompanying the paroxysm, and quite 
 distinct from it. She occasionally is heard to speak, and when 
 she does so, it is to " lament her infirmity of speaking in her 
 sleep," adding a reflection by way of comfort to herself, " how 
 fortunate it was she did not sleep among the other servants, as 
 they teased her enough about it as it was." The mind carried 
 a burden of sorrow on account of the abnormal condition of 
 brain which had been induced. At an advanced stage in the 
 history of the case mental activity is brought into co-operation 
 with the brain excitement. By an appeal to her through the 
 organ of hearing, she is led to take account of the presence of 
 others, and to answer their questions. This involved a serious 
 addition to the already dangerous excitement of brain, and a 
 
xni.] BRAIN DISORDERS. 409 
 
 disastrous end became certain. When out of the paroxysmal 
 excitement there was no manifestation of intellectual power. 
 She showed no power of musical effort when it depended on 
 voluntary imitation. She had no recollection of her musical 
 performances during sleep. She was slow in receiving in- 
 struction, and had no educational advantages fitted to develop 
 the intelligent nature. In strict harmony with this, it is re- 
 corded that when the brain injury was becoming apparent, her 
 utterances in sleep were " the babblings of a vulgar mind." 
 
 2. Intelligent self-control may avert insanity. 
 
 After the lengthened consideration of the manner in which 
 insanity may be induced, I shall not devote large space to the 
 power which may be wielded for maintaining self-government 
 when subjected to disturbing brain affections. If a person con- 
 template abnormal experience in its true light, if he distinguish 
 between personal activity and induced malady, if he have pre- 
 viously acquired habits of self-government, and bring them 
 into use under intelligent recognition of the facts of the case, 
 he can be his own physician in a most effective way. He will 
 value the co-operation of friends and the counsel of the' ex- 
 perienced physician ; but chiefly will he deal with the situation 
 as imposing upon himself a special duty, cessation from the 
 brain work, or separation from the disturbing influence which 
 induces excitement ; and he will resort to muscular activity, 
 open-air exercise, variety of scene, variety of interest ; in short, 
 every kind of occupation which favours a healthy physical 
 condition, with temporary abandonment of mental effort. I 
 speak of this as duty ; it is the one pressing demand of moral 
 life for the time being. This single consideration has deter- 
 mining value for all treatment of brain disorder. In sight of 
 it Dr. Maudsley has properly raised the question, " How far is 
 a man responsible for going mad ?" To this he replies — " This 
 is a question which has not been much considered, yet it is one 
 well worthy of deep consideration ; for it is certain that a man 
 has, or might have, some power over himself to prevent in- 
 sanity. However it be brought about, it is the dethronement 
 of will, the loss of the power of co-ordinating the ideas and 
 feelings; and in the wise development of the control of the 
 will over the thoughts and feelings, there is a power in our- 
 
4io THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 selves which makes strongly for sanity." 1 Such " wise devel- 
 opment of the control of the will " as is here commended, be- 
 longs to the normal life of man, whether he be educated or 
 uneducated ; but in saying this, it is granted that there is a 
 personal control superior to brain action, and which may keep 
 ascendency in midst of the disturbing experiences of a disordered 
 brain. This declaration, confirmed as it is by a large body of 
 evidence, and brought into application by the physician in his 
 treatment of sufferers, affords definite and very express testi- 
 mony to the superiority of mind over brain. 
 
 1 Responsibility in Mental Disease, p. 268. 
 
xiv.] THE HIGHER FORMS OF MENTAL ACTIVITY. 411 
 
 CHAPTER XIV. 
 
 THE HIGHEE FOKMS OF MENTAL ACTIVITY. 
 
 In order to complete the present inquiry, there still remain 
 for consideration all the higher departments of intellectual 
 activity familiar to man. Hitherto we have dealt with mental 
 action, as it is closely related with bodily activity. Now we 
 pass up into a higher region, where mind is at the maximum 
 of activity, body at the minimum. Here we leave behind us 
 the use of the senses, having already ascertained the conditions 
 regulating their activity, and what is the kind of knowledge 
 they afford. Now we come to inquire how that knowledge is 
 arranged, classified, and put to higher use, and how mind rises 
 to problems and ranges of thought higher than any included 
 within the area of the sensory. Here also we pass from all 
 that is concerned with the management of the muscular system 
 and mere bodily activity, including activity of motor nerves 
 and our use of muscular power. Now we must consider 
 what higher forms of human thought and activity there are 
 concerned with the acquisition of scientific knowledge and the 
 guidance of life as a whole. Here we come in sight of the 
 higher reaches attainable by man as a thinker, as these stand 
 clearly in view of men generally, so that the sight of them has 
 influenced the whole history of our race, even though they 
 have been explored by only a few, as adventurous travellers 
 attempt the Alpine heights. In the higher forms of mental 
 activity concerned with the guidance of conduct, or with 
 scientific questions, or with more abstract and speculative 
 problems, we find the distinguishing characteristics of human 
 life. So long as we are dealing with comparative anatomy 
 and physiology, we are contemplating man's participation in 
 animal life, and affinities with the animals. Even when we 
 study the comparative intelligence manifested in animal life, 
 
412 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 we rise to a level onlv a little higher, where we find our- 
 selves separated from lower orders of animal existence, but 
 still closely allied with higher orders, which may thus far he 
 recognised as the companions of man in his activities. But 
 when we come to contemplate man purely as a thinker, and 
 consider the vast work which has been achieved by him, of 
 which literature, poetry, art, science, and philosophy, present 
 the evidences, we recognise man apart from all other orders 
 of being in the universe. Here there is no companionship of 
 animal life. Man moves alone on a higher altitude, and 
 works unaided by lower forms of life which render service in 
 subordinate work. We discover and discriminate the specific 
 characteristics of human life, peculiar but common to the race, 
 at the same time marking the higher achievements of some, 
 and forecasting the possibilities of progression for each indi- 
 vidual and for the race as a whole. Here, for the first time iu 
 the whole course of the present inquiry, we reach the vantage- 
 ground whence we can see the true place of man in the scale 
 of being. By looking from this position downwards upon 
 lower orders of being to which the present height is inac- 
 cessible, we see, as we could not from a lower point of obser- 
 vation, how far man's position is above that occupied by the 
 most highly endowed animals. 
 
 We are now, then, to contemplate man as a thinker. In 
 doing so, it becomes needful to distinguish certain departments 
 of thought ; the intellectual, or that which is concerned with 
 the understanding of things ; the moral, or that which takes 
 cognisance of the regulation of a higher life, in accordance 
 with a higher type of law known to a rational being ; and the 
 religious, which has regard to man's relation to an invisible 
 order of things, and to an Absolute Being, as the source and 
 governor of all things finite, equally the visible and the in- 
 visible. In all these departments the specific characteristics 
 of human thought are apparent, as they are common to all the 
 three. We find ourselves amongst the generalisations, the con- 
 ceptions, the inductive and deductive processes, all of which 
 are proved to be familiar to every human mind. The laws 
 which regulate the higher forms of mental activity are the 
 same in all the three departments. There is no distinction to 
 
xiv.l THE HIGHER FORMS OF MENTAL ACTIVITY. 413 
 
 be drawn between them in this respect. Yet are they so dif- 
 ferent as departments of thought, that some minds concern 
 themselves far more with one of the departments than with 
 the others. Some show an intellectual interest concentrated 
 chiefly on the understanding of things as existing in the mate- 
 rial universe, and the most qualified among such thinkers aim 
 at contributing their share to the advance of science. Some 
 who have little familiarity with these regions of research, 
 bestow much thought on the requirements of self-discipline, 
 the management of life as a whole, and the attainment of an 
 excellence towards which approximation may be made, even 
 while bodily strength is failing. Others enlarge this range of 
 thought by considering the relation of practical life to a system 
 of things greater than the visible — seeing the invisible and 
 eternal — and finding a harmony of existence in the absolute 
 excellence of the Deity. In this department also we find a 
 phase of higher mental activity concerned more with the intel- 
 lectual problems which urge the human mind into fields of 
 speculation, than with the requirements of a moral and religious 
 life. From these few statements it is apparent that there are 
 three departments of higher thought which are capable of being 
 regarded as rigidly distinct, while they afford common tests of 
 the power of human intelligence. If this last consideration be 
 kept in view, it will be seen that we have a common field of 
 testimony before us, even while we distinguish three depart- 
 ments of inquiry. Though some show an aptness for only 
 one of these regions of thought, and special interest in it, all 
 have some share in the thought which belongs to the three. 
 There is no mind which does not experience an influence from 
 the scientific, the moral, and the religious, or at least the specu- 
 lative thought of the race. We have a unity in the wide range 
 of thought which includes the three departments, and evidence 
 for the unity of our race in the fact that, in greater or less 
 degree, there is universal experience of the power of such 
 thought. The least scientific have some appreciation of the 
 advance which science makes, as appears from the difference of 
 thought amongst the slightly educated, in contrast with the 
 thought of the same class when science was in its infancy. 
 There is a gradual deliverance from superstitions as the result 
 
4H THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 of some intelligent application of the conclusions of science. 
 On the other hand, and at the other extreme, the enthusiastic 
 disciples of science find it impossible to restrict themselves to 
 science. In vain has it been proclaimed that we should cease 
 from the search for causes, and restrict ourselves to the study 
 of facts. The speculative tendency of the human intellect is 
 too strong to be restrained by such barriers. There is an 
 " ought " before which human intelligence will bow, and that 
 the more readily and reverently the longer it thinks of its 
 claims ; but that man should not think of things beyond the 
 range of his own experience is an " ought " which man as a 
 thinker will not recognise, and the more fully its import is 
 understood, the more certain it becomes that the suggestion 
 will be banished as a scandal to the race. While we as indi- 
 vidual thinkers occupy our little place in the expanse of time, 
 there is for us thought concerning the past and the future — 
 concerning the origin of existence of which we form a part, 
 and the continuity of existence — which is the natural fruit 
 of intellectual action on the facts of existence. And so it 
 has happened, after an ineffectual barrier was raised to debar 
 science from the search for causes, that physical science has 
 pressed forward to a metaphysical region, and has intensified 
 the interest of the whole civilised world in the two questions 
 concerning the origin of existence and its destiny. Such facts 
 as these show how important for us is the inquiry, What is 
 man, regarded simply as a thinker ? Towards an answer we 
 must investigate the three departments of thought into which 
 we have seen the higher forms of mental activity may be 
 divided. 
 
 1. The purely intellectual department of thought. 
 
 Within this division falls to be included all thought con- 
 cerned only with the understanding of things as existing. This 
 must embrace the entire range of such thought, from that of 
 the child who is concerned with the " how ? " and the " why ?" 
 up through all the varieties of thought belonging to the prac- 
 tical man, until we have reached science proper, the systema- 
 tised and rationalised order of things. Our problem is this, — 
 Can such ranges of thought be regarded as functions of nerve 
 tissue, "and explained under the laws of nerve action? To 
 
xiv.] THE HIGHER FORMS OF MENTAL ACTIVITY. 415 
 
 answer this problem in the affirmative is the task which those 
 have assigned to themselves who urge that thought is a func- 
 tion of brain. The task does not seem a very easy one, nor 
 does there appear great eagerness to undertake responsibility 
 for a completed demonstration. 
 
 A general outline of the range and conditions of this region 
 of thought will show the nature of the problem as con- 
 cerned with brain and mind, and the ground on which it 
 appears that brain is unequal to such work. Here we must 
 recall the results of previous inquiry as to lower forms of 
 mental activity. We have seen that perception of external 
 objects, as it belongs to human experience, implies in its 
 ordinary exercise comparison and memory. That is to say, to 
 observe objects as we do when we say coal, iron, stone, and wood, 
 is not merely to see certain things, but to compare, and to draw 
 upon the results of past observations. We have further ascer- 
 tained that management of motor activity, as it is known to us, 
 implies reflection and will. That is to say, we are well aware 
 that we consider within ourselves what it is best to do in given 
 circumstances, and after we have seen the course of action 
 clearly, we determine upon it, and the whole motor activity 
 which results is the product of our own determination, though 
 it could not have been accomplished without nerve energy and 
 muscular power. From examination of these lower orders of 
 activity we have found that comparison, — recollection of the 
 results of past comparisons, — inference, and volition, are all 
 characteristic of man, and cannot be accounted for under the 
 laws of nerve energy. This being true, still less can the higher 
 powers of intellectual activity be so explained, and the more 
 obvious does it become that mind is a superior order of exist- 
 ence, performing work unapproachable under the laws of nerve 
 action. 
 
 Advancing beyond the intelligent perceptions which con- 
 stitute the early exercises of childhood, the mind reaches 
 generalised truth, and forms representative conceptions of 
 things. These forms of activity do not depend upon a full 
 development of brain (see p. 13) ; they are carried on early in 
 life. At quite an early period the child is working with 
 generalised truths, representative conceptions and abstract 
 
416 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 terms. The circumstances of the child as resident in the city 
 or in the country have much to do with his mental activity ; 
 his food, and rest, and health of brain are necessary conditions 
 for observing things around, and thinking of what he sees ; but 
 all these are insufficient to account for the fact that from day 
 to day he is discovering more than he sees. The sensory and 
 motor systems of nerves, with the several adjustments of cellu- 
 lar tissue belonging to the nerve centre, will account for his 
 observations, and the amount of muscular activity he puts forth 
 under the interest which these observations awaken. But the 
 discriminating and classifying processes by which he gathers a 
 store of general knowledge concerning birds and fishes, and the 
 forces operating in the material world, cannot be so explained. 
 Brain power will account for what is common in the observa- 
 tions and wanderings of childhood's years. Superiority or 
 inferiority of brain power may afford the key to diversity in 
 quickness of observation, and in power of endurance, or readier 
 sense of weariness, during the rambles of a summer's day. 
 Superiority of brain action may explain the vividness of recol- 
 lection with which some recount the incidents of the day, in 
 contrast with what seems to be the comparative forgetfulness 
 of others. But when the children are silent and still, when 
 they are reflecting over things which have awakened their 
 curiosity, and when they come to their seniors seeking help 
 towards explaining how certain things happen, or why things 
 are arranged in a particular way, they are engaged with fornjs 
 of activity which are not accounted for by the laws of brain 
 action. It is not, indeed, to be thought possible that an expla- 
 nation of these forms of activity can be given irrespective of 
 brain ; but, after we have assigned to brain all that the most 
 advanced research warrants, we cannot complete a theory of the 
 facts, I refer for illustration here to the period of childhood, 
 because this is an essential part of our problem, that such 
 phases of intellectual activity as those described are not the 
 special occupations of mature years, but are possible to man at 
 a very early period of life. A human intellect with stores of 
 generalisations, representative conceptions, and inferences, has 
 a history long before the period when maturity of brain is 
 reached. Accordingly, even a child is scientific in the nature 
 
xiv.] THE HIGHER FORMS OF MENTAL ACTIVITY. 417 
 
 and form of his thought. He teaches himself by what he 
 observes, and is not merely taught by others ; he trains him- 
 self by the questions he addresses to others, as well as by 
 the suggestions which they bring to him. Nerve and brain 
 afford materials with which mind works; but in this more 
 advanced work the laws of rational procedure are quite distinct 
 from those of brain action. Brain activity provides common 
 material for all men ; but arrangement of things according to 
 diversity or resemblance, and inferences as to general character- 
 istics, proceed according to laws of intelligence which must be 
 applied by the thinker himself, the value of his inferences 
 being largely determined by the experience he has had in 
 such engagements. Here we are in a perfectly distinct region 
 of activity, where caution, thought, and perseverance bring an 
 enlarged result, caution and not pabulum, — thought and not 
 sensibility, — perseverance in a distinct line of activity, when 
 observations are meanwhile brought to a close, and the thinker 
 sits apart accomplishing work of a more advanced kind. 
 
 Here then we reach an essential characteristic of human life, 
 appearing at an early stage ; manifested throughout advanced 
 years by men of all classes, whether more or less aided by edu- 
 cational advantages ; and put to most efficient use by men of 
 scientific training, who in the higher walks of science only dis- 
 cover a higher degree of concentration, and a more persistent 
 use of the intellectual powers which are at the command of 
 all, and more or less exercised by all. 
 
 Along the line of these advancing degrees of intellectual 
 activity, we reach a better appreciation of the essential fea- 
 tures of human personality ; and here by consequence we come 
 more distinctly on the contrast between quality of brain and 
 range of intellectual attainment. The history of scientific 
 thought affords a good test of the relation of intellectual pro- 
 gress to brain power. There has been within less than a cen- 
 tury an immense advance in physical science. The stores of 
 knowledge added within that time are so vast that, when they 
 are contemplated as distinct achievements within a compara- 
 tively restricted period of human history, they present a con- 
 trast of the most extraordinary kind, with the boundaries of 
 human knowledge as previously recognised. Nevertheless, it 
 
 2 D 
 
4iS THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 is not maintained, as affording any part of the explanation of 
 this grand advance, that there has been some new development 
 of brain power in the history of the race. It is not affirmed 
 that we have seen the evolution of a more complex type of 
 organism than existed in the seventeenth or the fifteenth cen- 
 tury. It is continuity of thought, along with improved appli- 
 ances at command — not growing complexity of brain — which 
 accounts for recent results. It is not alleged that the average 
 brain of living naturalists is in advance of that of Cuvier, 
 weighing 64 ounces; or that the ordinary standard of brain 
 weight among the physicians of the present day is above that 
 of Abercrombie, which weighed 63 ounces. The microscope 
 has multiplied our powers of observation, and quite changed 
 our modes of teaching science ; and our literature has placed 
 within easy reach of the reader what could not formerly have 
 been gathered as the reward of half a lifetime of study. These 
 are the direct and immediate explanations of the difference. 
 There are consequently more workers in the department of 
 science, and all of them are better equipped. Is, then, the 
 power to use these advantages to be found in greater brain 
 activity, or in the continuity of thought which works accord- 
 ing to the old methods upon the newly acquired materials ? 
 I answer, the explanation is to be found partly in both, but 
 chiefly in the latter. 
 
 Eecent advance in science implies a larger and more minute 
 application of observation, and that involves a considerable 
 increase of brain work. If we take the ordinary student of 
 science as a test, there is for him a greater demand upon the 
 power of vision, and all the brain work which this presup- 
 poses, than there was for the science student of former days. 
 This the microscope has made possible, and hence the enlarged 
 demand for a trying and exhausting use of brain power. The 
 result of this may by and by appear in a more common abate- 
 ment of the power of vision. If short-sightedness should be- 
 come more general in the twentieth century than it has been 
 in the nineteenth, there will be a natural explanation. But 
 granting this more minute and exacting demand upon brain 
 power which observational science now makes, we must also 
 grant the natural law of development of the organ through 
 
xiv.j THE HIGHER FORMS OF MENTAL ACTIVITY. 419 
 
 means of continuous exercise in a given manner. Tn accord- 
 ance with what has been said (pp. 55, 56) indicating that con- 
 tinuity of natural exercise involves development in individual 
 history, it will follow that, if injury to the organ by overstrain- 
 ing be shunned, there will be a contribution to brain devel- 
 opment in the concentrated work which scientific research 
 demands. The result may be a more highly developed brain in 
 a larger number of cases than could have been if all students 
 of science had been restricted to the old methods of observa- 
 tion. The influence of this upon the race may appear in 
 accordance with a law of heredity. But from this it will not 
 follow that there is a reasonable probability of a greatly 
 higher brain development during the present century than was 
 formerly attained. There was, under the old methods, the 
 same demand upon observation for reaching the results then 
 attained, although the appliances at command were fewer. 
 And, indeed, the scantier provision of instruments afforded, in 
 some measure, a greater test of the intellectual work done. 
 Hence it seems natural to conclude that what is in promise for 
 us is a wider or more general diffusion of high brain develops 
 ment, rather than a greatly higher development in special 
 cases. But it does not follow from a generally high brain 
 development that there will be a proportionate intellectual 
 development. This depends upon a law of development find- 
 ing exercise in a different sphere. If the student of science 
 reason as carefully and as minutely as he now observes, there 
 will be an equivalent intellectual development. But the 
 demand upon individual power is greatly increased by the 
 wider range of activity. And it cannot be a marvel if skilful 
 observers do not always prove themselves equal in reasoning 
 power. The more exacting requirements of observational 
 science have their disadvantages from an intellectual point 
 of view. So much needs to be done in the way of minuter and 
 more intricate observations, that less can be done by the same 
 workers in the form of independent thought. The very eager- 
 ness and intensity of interest felt in recording new observations, 
 to some extent unfits the mind for withdrawing to a standpoint 
 sufficiently remote for seeing the proportion of things. If the 
 first demand of modern science be for observation, its second 
 
420 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 and higher is for thought which shall grasp the widening re- 
 sults, and discover their true meaning. Observational power 
 and thinking power may not prove equal; but, in harmony 
 with all that is now being recognised as to the division of 
 labour, it may follow that the thinking work may be done 
 by those who have taken a comparatively small share in 
 the practical and very laborious work of observation. This 
 distinction between lower and higher scientific work is now 
 quite generally acknowledged. The thinking of Newton was 
 something very different from the observation which results in 
 the discovery of a new planet, yet persistent observation is not 
 maintained, save on the warrant of the prior thought. The 
 thinking of Dr. Abererombie was a different exercise from the 
 researches of Sir Charles Bell, but Abererombie was an observer 
 in his own way, and with his own appliances, and was much more 
 of a thinker than an observer, because of the greater extent to 
 which he was forced to depend upon inference from symptoms 
 than upon observations as to minute structure. If, therefore, we 
 only make account of the progress of scientific knowledge, we 
 shall see that a prior thought prepared the way for the minuter 
 observations of the present day, and if the Ml significance of 
 our observations is to be deciphered, we shall want in advance 
 of all observation the same broad, abstracting, generalising 
 thought which did so much for our race before microscopic 
 investigation began. And this is work which does not find 
 its explanation in the known laws of brain activity. It is 
 not the difference of brain development which explains the 
 difference between these three men, — a man of ordinary educa- 
 tion, a man who is a scientific observer, and a man who works 
 even more in a region of thought than in that of observation. 
 When we contrast the two extremes, the words of Sir Charles 
 Bell indicate what scientific inquiry must naturally suggest, 
 that differences in intellectual power are not accounted for by 
 brain diversities. Bef erring to " the varieties of the human 
 head depending on national peculiarities," and the results of 
 comparison of skulls as well as brains, he says by way of 
 warning,—" It is taken for granted that we who exercise our 
 best faculties within the four walls of a house, must have a 
 development of brain beyond what the free-dweller in the 
 
xiv.] THE HIGHER FORMS OF MENTAL ACTIVITY. 421 
 
 plains or forests of what is termed a new country can possess. 
 I believe, on the contrary, that man in his state of nature has 
 imposed upon him the necessity of bringing into operation 
 quite as many faculties of mind as the man at his desk ; and 
 that, from the brain being exercised in every use to which the 
 external senses are put, its volume is not inferior to that of the 
 individual in civilised life. We must take along with us this 
 consideration, that the exercise of our external senses infers an 
 accompanying activity of brain ; that of the nervous apparatus 
 appropriated to the senses, it is the exterior part alone that is 
 given to the eye, ear, nose, tongue ; the internal part, forming 
 the sensorium, is in the brain. Eemembering this, and that 
 the powers exercised by the savage are not instincts, as in the 
 brutes, but operations of the mind calling the brain into action, 
 I am unwilling to grant that any measurable deficiency in its 
 mass, as a whole, is likely to be perceived. Were it really so, 
 we should find the gamekeeper inferior to his master in a 
 greater degree than my experience warrants." 1 Thus Sir 
 Charles Bell suggests that an active out-of-doors life may as 
 truly supply the conditions for good brain development as a 
 life more studious and sedentary. Still more important because 
 of the directness of testimony on the matter, along with the 
 special qualifications of the writer, which make him an acknow- 
 ledged authority, are the statements of Dr. Herbert C. Major, 
 bearing upon the question " to what extent the degree of intel- 
 lect possessed by an individual during life may be estimated 
 by an examination of the brain after death." He says, it is " a 
 conclusion which we can scarcely avoid, that, as a general rule, 
 great intellectual power is associated with a large and heavy 
 brain. . . . Unfortunately, however, this is by no means an 
 invariable rule, for instances are not wanting in which the 
 brain representing superior intellect has not only not surpassed 
 another, lower in the intellectual scale, but has even fallen 
 below it." Passing next to the number and depth of the con- 
 volutions, his testimony runs thus : — " It has been found that 
 increased depth and number of the convolutions coincide in 
 many instances with superior intellectual power. But here 
 again, having arrived at a general conclusion, based on observa- 
 1 Anatomy and Philosophy of Expression, p. 72. 
 
422 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 tions which are good and true, we are met by the stern fact 
 that this is not always so, and that instances are not wanting 
 in which the exact opposite is the case." Eeferring next to 
 the minute structure of the brain, he says:— "When the 
 question arises as to the difference histologically between two 
 brains, one of which represents a high, the other a low standard ' 
 of intellect, we are compelled to admit that the answer to the 
 question lies beyond our reach." After referring to specific 
 gravity and pathological conditions, Dr. Major presents his 
 general conclusion in the following terms : — " From these con- 
 siderations it follows that we may have presented to us for 
 examination two brains, equal in size and weight, equal also, so 
 far as can be ascertained, in the number and depth of convo- 
 lutions — that is to say, in the extent of the grey matter, the 
 latter being also similar in its minute structure, and yet one 
 may represent great intellectual power, the other quite an oppo- 
 site condition." 1 
 
 When we seek the explanation of high intellectual effort, it 
 must be found in a power superior to brain. It is not thereby 
 implied that a poor brain would not hinder such effort, but that 
 a good brain is insufficient to account for it. Clear evidence 
 on this point will be obtained by considering the special nature 
 of intellectual effort, and the laws in accordance with which it 
 proceeds. Classification of observed facts, application of the 
 laws of inductive logic, inferences under warrant of the law of 
 causality, and an auxiliary play of imagination filling in the 
 blanks needful to support a rational hypothesis, — these are 
 phases of intellectual activity in the study of scientific pro- 
 blems. There is nothing in the physiology of brain to give 
 plausibility to the suggestion that the nerve centre is equal to 
 such work. The scientific inquirer is certainly not in any 
 way separated from experience connected with sensory and 
 motor activity, and with the complicated range of reflex 
 action. But he is occupied with a range of activity far above 
 all that is implied in the functions of a nerve system, so far 
 as these functions have been scientifically ascertained. He 
 carries through a voluntary and purely intellectual arrange- 
 ment of facts; he projects conceptions which come from an 
 1 West Riding Reports, vol. ii. pp. 157-159. 
 
xrv.] THE HIGHER FORMS OF MENTAL ACTIVITY. 423 
 
 inner sphere of intelligence, and the product is a rationalised 
 scheme of existence which has significant value only amongst 
 intelligent beings. The solution of any intellectual problem 
 depends on personal concentration, continuity of thought, and 
 persistence of wide-ranging reflection. The result is not such 
 as could be estimated according to the cerebral development of 
 the thinker. However good that development be, it would 
 secure little without self-directed and continuous effort. This, 
 then, is the distinguishing feature in the life of thought, in which 
 the value of procedure is according to the concentration of 
 personal intelligence and conformity with the laws of reasoning. 
 Concentration of thought, not as the result of impression from 
 without, but as the result of personal determination within, is 
 not to be accounted for under the known laws of brain action. 
 
 2. Thought as concerned with the regulation of personal life. 
 — A self-regulated life is a special characteristic of man. 
 Government of conduct by intelligence is the grand possi- 
 bility for all men, educated and uneducated. In this we see 
 complete separation of man from all lower orders of beings, 
 and a range of intellectual activity quite transcending the 
 functions which can be assigned to brain. Moral life is regu- 
 lated, not according to appetite or personal inclination, nor 
 according to outward circumstances, and yet not apart from 
 these, but in view of an ideal standard contemplated and ap- 
 plied by the individual. In studying this feature of human 
 life, there is no need for dwelling upon conflicting ethical 
 theories as to the source of our knowledge of moral distinc- 
 tions. The question now to be discussed is not in any way 
 affected by the competing claims of rival philosophic schools. 
 Whether moral law is intuitively known, or is an induction as 
 to general utility founded on the common law of the pleasur- 
 able, need not concern us here. All ethical philosophers, to 
 whatever school of thought they belong, are agreed in this — 
 that there is a moral standard which men ought to revere and 
 struggle to fulfil. Whether philosophic thinkers prefer to say 
 that there is an absolute law of right, or that " the greatest 
 happiness of the greatest number " is the test of rectitude, the 
 grand characteristic of moral life is not disputed. All are 
 agreed that the practical or moral life is, as Aristotle said, " an 
 
424 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 energy of the soul, according to right reason" 1 — "a kind of 
 well-doing and well-living." 2 It is as a thinker that man 
 shows his superiority in the direction of his conduct. He 
 reflects upon what ought to be, decides for himself the ques- 
 tion of personal duty, and acts in accordance with a rule of 
 life standing out before his mind as a rational law of activity 
 which he must apply for himself. For illustration we may 
 take the Utilitarian formula of right conduct, — "the greatest 
 happiness of the greatest number." This maxim practically 
 signifies that benevolence is an imperative rule of conduct. 
 The simplest application of such a rule implies that a man 
 is first a thinker in order to be a moral agent ; that he has 
 some conception of what constitutes the good of others ; that 
 he perceives how his conduct can contribute towards it, and 
 that he recognises an obligation to aim at its attainment. The 
 overt action which results from his recognition of duty may 
 readily enough be accounted for under physiological law, but 
 the reflective process which precedes the overt act cannot be 
 so explained. The somatist 3 who would bring all human con- 
 duct within the scope of organic action, has here a crucial test 
 of his theory. No attempt at scientific explanation has yet 
 been submitted from the side of the somatists ; and we may 
 reasonably claim that the defenders of the theory that thought 
 is a function of brain offer their defence at such a* testing-point. 
 That the nature of this test may more clearly appear, it 
 is desirable to notice how complete is the contrast here 
 presented between animal and rational life. The nature of 
 man has much in common with lower forms of animal life, 
 on account of common possession of a sensori-motor system, 
 similarly related to a sensible world. Accordingly, men and 
 animals alike are liable to have the sensitive nature acted upon, 
 and thereby to have certain impulses, such as the appetites 
 and other desires, roused within them. It is equally natural 
 for both to gratify such desires, thereby illustrating common 
 phases of animal life. Both are liable to have the force of 
 
 1 Nicom. Ethics, I. vii. » lb. i. viii. 
 
 3 I prefer the terra " somatist " to designate the upholder of the theory 
 that bodily organism embraces the whole nature of man, rather than " mate- 
 rialist," which is resented as implying unmerited imputations. 
 
xiv.] THE HIGHER FORMS OF MENTAL ACTIVITY. 425 
 
 such desires checked by adverse influence exercised from 
 without. A sudden accession of fear will at once restrain the 
 power of appetite. This is equally natural in the case of man 
 and animals, illustrating a common restraint of animal life. 
 But the conception of duty in the human mind is at once a 
 restraint upon indulgence, and a direction of activity, of which 
 animal life affords no illustration. If we compel animals to 
 do what we desire, and if by long training we familiarise them 
 with our requirements, we act both upon their fear and their 
 fondness, but the utmost achieved in this way is the result of 
 compulsion, a result which is quickly lost if the external de- 
 mand be withdrawn. The most enthusiastic upholders of the 
 power of animal intelligence have not suggested that animals 
 reflect upon a rule of conduct. It is, however, the most 
 familiar exercise of human life to consider what ought to be, 
 and afterwards to judge of the extent to which that which has 
 been achieved meets the requirements of personal obligation. 
 
 Thus we must recognise a common experience for man and 
 animal connected with activity ; and, quite in advance of this, 
 a special exercise on the part of man, leading to a vastly higher 
 form of activity. Both men and the lower animals find a large 
 field of attraction in the outer world ; both are acted upon by 
 the qualities belonging to external objects, and thus have their 
 inclinations or desires awakened, impelling them to seek 
 gratification. Under such influence, both have the object of 
 attraction without ; both are moved by strong impulse within ; 
 and both are inclined to immediate action under the awakened 
 impulse. This common experience may be illustrated by the 
 following figure : — 
 
 Sphere of Organism. External Sphere. 
 
 Observation, ^a 
 
 Dcblre. 
 
 Opportunity. 
 
 Fig. 42. — Diagrammatic representation of experience of external influence common 
 to Man and Animals. 
 
 In the common experience here illustrated, observation is 
 
426 
 
 THE RELATIONS OF MIND AND BRAIN. 
 
 [CHAP. 
 
 concentrated on the opportunity of gratification afforded by 
 external circumstances. The common result, according to the 
 law of sensitive life, is desire of gratification, and under the 
 same law the common tendency is to seek satisfaction of the 
 desire. The sole law of animal life in such circumstances is 
 active gratification. The sole check on such action is hindrance 
 from without, either preventing gratification or awakening a 
 new impulse, such as fear, which destroys the desire previously 
 aroused. But with man there is a higher possibility, a new and 
 higher source of activity belonging to a more complex nature, 
 an impulse coming from an inner sphere, more remote from 
 that external sphere whence animal life is ruled. There is 
 with man the power to direct his observation on the desire 
 moving him to seek personal gratification, the power to reflect 
 upon the Tightness of self-gratification in the circumstances, 
 and the power to hold up before the attention a higher law of 
 life than that which desire affords. While these powers are in 
 exercise, the desire, still present, is held in check; and at 
 length, as the result of the reflective process, the will of the 
 agent may determine the course of personal activity in accord- 
 ance with a recognised law of rational life, either gratifying 
 the desire, or withholding from such gratification. This higher 
 exercise is illustrated by the following figure : — 
 
 Inner Sphere. 
 
 External Sphere. 
 
 Law. 
 
 Reflection. 
 
 Observation. 
 
 ^ 
 
 y 
 
 Desire. 
 
 Opportunity. 
 
 Fia. 43. — Diagrammatic representation of the exercise peculiar to man in governing 
 the Desires. 
 
 When observation is directed on the Desire as an impulse 
 to action, and away from the opportunity of gratification, Re- 
 flection is turned on the question whether the Desire ought to 
 be allowed in the circumstances ; for decision of this, attention 
 
xiv.] THE HIGHER FORMS OF MENTAL ACTIVITY. 427 
 
 is turned inwards on the Law of rational life, not outwards 
 upon Desire, or upon the Opportunity for its gratification ; and 
 when a general rule of conduct has been contemplated, the 
 Will of the agent becomes the determining power in view of 
 the rational law. The only alternatives open to those who 
 would attribute all to organism are, either denial of the possi- 
 bility of this higher intellectual exercise, or explanation of it 
 under the laws of brain action. The former alternative is not 
 available. It is simply impossible to deny such rational 
 exercise concerned with the guidance of life. The latter alter- 
 native is the only one which can be regarded as offering an 
 avenue for explanation to the inquirer who grants the existence 
 of nothing higher than brain. But physiology is so far from 
 having surmounted the difficulties here, that it has not even 
 the means of reaching them. Eeflective exercise as to a law 
 of rational life cannot be brought under external observation ; 
 discovery concerning sensory and motor nerves, and the laws 
 of innervation, does not include the forms of action to be 
 explained; histological investigation has produced nothing 
 bearing upon the facts. Physiology has not 'shown itself com- 
 petent even to enter the region of human life with which we 
 are now concerned. 
 
 For those who seek to explain all by the ascertained func- 
 tions of brain, there would be some encouragement if, in absence 
 of direct evidence, it could be shown that man must have 
 advanced to maturity of brain development before he begins 
 to occupy himself with an abstract law of rational life. But 
 this does not hold true. On the contrary, a child four years of 
 age is found to concern itself with rational laws of life, insist- 
 ing that deceit is wrong, and injustice, and cruelty. And such 
 a child will judge others, and condemn them for violation of 
 proper rules of conduct, and will make no allowance for an old 
 deceiver or oppressor. Immaturity of brain interposes no 
 obstacle to reflection on right guidance of conduct. The 
 hypothesis which assigns all to brain action has its perplexities 
 greatly increased by the facts of early life. For abatement of 
 this perplexity, reference is commonly made to the power of 
 education over the minds of the young. But retreat in this 
 direction is of no service, and is clearly an avowal of weakness. 
 
428 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 How the youthful mind gains possession of the abstract laws 
 of conduct may, as has been said, be treated in this discussion as 
 an open question ; the real point here to be determined is, how 
 the child by an exercise of his own thought applies the law 
 to the circumstances in which he is placed, and makes that 
 law a test of the conduct of others under whose influence 
 he lives. A child is the judge of a grown man, and a correct 
 judge, when he pronounces condemnation on pretences and 
 falsehoods of his seniors. No doubt education may do much 
 to influence the thought of a child. It may do much harm 
 as well as much good ; under its influence a child may be led 
 to do what it began by condemning. But the beginning of all 
 education, whether it be for good or for evil, is the existence 
 of a mind capable not only of observing, but of reflecting. 
 What we need to have explained is the process of thinking, 
 and that in such a manner as to involve application to conduct 
 of a rational law of life, in contrast with action under an 
 impulse of self-gratification. Education implies the exist- 
 ence of rational power, and the possibihty of development by 
 exercise, as all our powers are developed. What is called 
 " education," including under that name the influence of the 
 family circle, of society, and of current opinion, may be good 
 or bad according to the direction in which it leads, inclining, for 
 example, either to the condemning or excusing of deception. 
 But an application of some general law is implied even in the 
 most confused of the reasonings which deal with moral life. 
 Accordingly, if we take the worst which a bad education can 
 do, it does not include within its results the satisfying of the 
 intelligence of a child, whether young or old, that it is right 
 he should be deceived. 
 
 These considerations lead naturally to a phase of moral life 
 still further in advance, that is, the difference between reflec- 
 tion as to the law of rational life, and the application of it in 
 the government of conduct. This introduces the relation 
 between Intelligence and Will. Practical thought is for guid- 
 ance of action ; it is reflection on a rational law for self-deter- 
 mination in order to the attainment of a rational life. The 
 possibility of acting according to such law, in acknowledgment 
 of an authority belonging to it, and either against personal 
 
xiv.] THE HIGHER FORMS OF MENTAL ACTIVITY. 429 
 
 inclination, or not at its dictation, is characteristic of a rational 
 agent. To make such possibility an actuality is the true end 
 of reflection on matters of duty. And it is just as man reflects, 
 and afterwards acts under guidance of thought, that he rises' 
 in the scale of being, illustrating the pre-eminence of rational 
 life. The possibility of moral progress thus becomes one of 
 the problems of human life, and must be a distinct test of the 
 sufficiency of any theory of our nature. To stand between the 
 allurements of sense and an ideal of rational life ; to recognise 
 the duty of guarding against the former, and aiming at the 
 fulfilment of the latter ; and to accept it as one's life-work, to 
 rise by years of patient effort towards this rational ideal : these 
 are possibilities which seem to be altogether inexplicable under 
 a scheme which traces the whole energies of human life to the 
 action of nerve cells. 
 
 The best test of the sufficiency of evidence and of reasoning 
 belonging to the two conflicting theories of human nature will 
 be found in the contrast between a low and a high type of 
 moral life, abundantly illustrated in the contrasts of our social 
 experience. This contrast implies, in the one case, descent 
 towards animal life ; in the other, obvious superiority to animal 
 life, and wide separation from it. That it is possible for man 
 to descend towards the level of the animal, we have, alas ! too 
 much evidence to prove. A life of sensual indulgence means 
 increasing severance from a life of intelligence. The man who 
 moves down on this inclined plane towards the lowest levels 
 of human existence, still shows so much of man's higher 
 nature as to be painfully sensible of his degradation. But as 
 the descent is continued, the exercise of reflection becomes less 
 frequent, and less efficient. The cravings of a disordered 
 nerve system become more clamant and tyrannical; we wit- 
 ness the wreck of human nature, swayed by impulses no 
 higher than those of the animal, involving a condition of 
 physical existence lower even than ordinary animal life ; and 
 in the utter loss of self-control, need arises for management 
 by others who can see what is required, and are prepared to 
 undertake the needful and benevolent work of caring for one 
 who is self-debased. The testimony coming from a phase of 
 life so dreadfully disordered, is that a higher than a merely 
 
430 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 physical existence is the normal life of man. It illustrates 
 what the physical frame may become, if intelligent regulation 
 be surrendered, namely, something lower even than is possible 
 to the animal life which is governed by animal impulse and 
 nothing higher. The greater.depth of degradation becomes in 
 some sense a measure of the eminence from which the nature 
 has descended. Simply as degradation, it brings out with 
 special prominence the fact, that intelligent regulation is the 
 law of human life, and that a theory of its possibility is an 
 essential requisite for an adequate theory of human nature. 
 
 By contrast we have the progress of the moral life, from 
 which we obtain some clearer measure of the problem involved. 
 Deliberate application of rational principle as the guide of 
 human conduct enables a man to gain the mastery over cir- 
 cumstances and the control of present inclinations. As he 
 advances he attains to a life more truly self-regulated. It is 
 thus possible for a man to ascend far from the level of merely 
 animal life, and the farther he advances in this direction the 
 more obviously does he exemplify the true excellencies of 
 humanity. What is wanted, therefore, for the present purpose 
 is, analysis of that kind of regulation of conduct which we 
 describe as intelligent or rational. All are agreed that what 
 is intended is that the agent have some reason for what he 
 does, and that must be something better than individual inclin- 
 ation. It must be a reason which will bear to be inspected by 
 other men, and which will in fact prove itself to be a rule of 
 conduct applicable to men generally. This is the kind of 
 reason which we contemplate when we insist on the distinc- 
 tion between right and wrong. It will be a reason sufficient 
 to call for self-denial, or even suffering, and for concentrated 
 effort and long toil, if all these things are needful in order that 
 personal life may be kept under its direction. Eational life, 
 therefore, implies personal superiority to impulse, and regard 
 to an intelligible rule of conduct as a uniform law of activity. 
 It means, on the one hand, that impulse may be gratified or 
 restrained according to the decision of the agent ; and on the 
 other, that thought must govern. There is no call to enter 
 here on a lengthened inquiry as to the merits of the contro- 
 versy concerning the power of the strongest motive. The 
 
xiv.] THE HIGHER FORMS OF MENTAL ACTIVITY. 431 
 
 question before us can be kept within narrower boundaries. 
 Whatever be the strength of the impulse which arises, can it 
 be controlled, or is man subject to it and irresponsible ? Or, 
 let the case be put at the worst, and let us suppose that a 
 sudden impulse does actually master a man, and that he acts 
 under its influence, and in doing so acts irrationally. He 
 blames himself for his conduct ; he repents of it as an evil 
 and dishonourable thing; he resolves to prove himself supe- 
 rior to such impulse in the future. We need an explanation 
 of these phases of thought, either on a theory of brain or on 
 a theory of mind. I have not seen any exposition of the func- 
 tions of brain which can be taken as a scientific account of 
 such mental occupation. The more carefully the exercise is 
 analysed the more difficult will it appear to include the facts 
 within the forms of brain action. There is, indeed, a feeling 
 of uneasiness immediately when the wrong action is done, but 
 that is not what we seek to have explained. Such feeling may 
 pass off, and the agent may yield to the same conduct again, 
 and have less feeling than on the former occasion, and he may 
 continue in similar conduct until the uneasy feeling entirely 
 passes away. A shameless life is unhappily a possibility. 
 What we need to have explained is moral progress by the 
 pathway of reflection. However important sadness of feeling 
 may be as a check on continuance in evil-doing, it is not feel- 
 ing, but thought — clear and strong thinking as to the true law 
 of conduct — which can account for a mastery over strong im- 
 pulse. If any one prefer to represent the activity of human 
 life under the analogy which Force supplies — though the 
 analogy is far from complete — then it is the force which be- 
 longs to quiet deliberate thinking which is the true source of 
 higher moral life. He who would explain moral progress must 
 see the thinker contemplating a law appreciable only to intel- 
 ligence, and drawing from that contemplation the form of his 
 future career, and the moral purpose which will determine 
 activity, and gain an ascendency over appetite and passion. 
 The extent to which such reflection is carried on, and the 
 degree of its application to conduct, determines the differences 
 of moral progress in the history of men. Contemplation of 
 moral law, and consequent regulation of impulse, are phases 
 
432 THE KELA TIONS OF MIND AND BRAIN. [chap. 
 
 of activity belonging to an inner life quite separated from the 
 region of sensibility. So complete is this separation that it is 
 impossible that sensibility could afford a scientific explanation 
 of them. They are so obviously superior, involving an actual 
 overruling of personal inclination, that it is impossible to trace 
 their source " to the two elementary functions of sensation and 
 motion, and their conversion into reflex action," unless a- lower 
 phase of activity can produce a higher. It is not as a sentient 
 being, but as a thinker capable of isolating himself from pre- 
 sent surroundings, that man is able to take a survey of his 
 past history, to regard it as a whole, to judge of it in the light 
 of a definite standard of human excellence, to mark its defici- 
 ency, and to contemplate with satisfaction a course of effort and 
 conflict in order to attain a high form of life. The essential 
 feature in every effort which seeks to carry out such determi- 
 nation is prominent in the conflict waged with the desires and 
 tendencies of the sensitive nature. That feature is concentra- 
 tion of thought in opposition to the impulses of a lower nature, 
 so as to establish over them a complete ascendency. This is the 
 condition of rational self-government, which stands in contrast 
 with the law of sentient life as regulated from the nerve centre. 
 3. Thought as concerned with the Absolute Being and Sis 
 government of the universe. — The thought directed towards 
 self-government has naturally led on to thought concerning a 
 higher government, exercised over all moral agents, the tokens 
 of which are found in the rational laws of life. It is charac- 
 teristic of human thought that it advances from lower to higher, 
 and still higher conceptions, until it concerns itself with the 
 Absolute or Self-existent Being, as the true source of all finite 
 existence. And this advance is the more deserving of atten- 
 tion, that it is obviously true, as Kant has urged, 1 that an in- 
 ference from the finite to the Infinite is incompetent, as con- 
 taining more in the conclusion than the premises warrant. 
 All the more striking, therefore, as testimony concerning the 
 action and range of human thought, is the fact that men have 
 so generally recognised the existence of an Absolute Euler of 
 the universe. That the visible suggests the invisible ; that the 
 finite suggests the infinite ; that the human suggests the Divine, 
 1 Critique of Pure Reason, Meiklejohn's. Translation, p. 883. 
 
xiv.] THE HIGHER FORMS OF MENTAL ACTIVITY. 433 
 
 are facts which can be established by a wide induction from 
 the literature of civilised nations and the religious rites of the 
 uncivilised. The scientific value of the speculative and reli- 
 gious thought which has found currency in the world is not 
 here the question, but the possibility of such thought. Exist- 
 ence and a place to move in have never been found sufficient 
 for men, as they have proved sufficient for the animal whose 
 hunger has been satisfied with the pasture. The marvel to the 
 mind of Des Cartes, when he considered the imperfection of 
 his own nature, and the doubt in which he was often involved 
 as to the certainty of things around him, was the conception he 
 had of an all-perfect Being. 1 The primary question for him 
 was not the existence of God, but the conception of such a 
 being. And the source of such thought must at this point in 
 our argument be the question pressing itself on the considera- 
 tion of those who attribute the highest activity of man to 
 organism. To account for the fact that the thought of man 
 does not exhaust itself with the materials which observation 
 supplies ; does not stop short without a theory of the universe 
 as a whole; and even rises to the conception of an Abso- 
 lute Being, — to account for all this involves a heavy task for 
 him who seeks to include all within the functions of brain. 
 Thought as to Absolute Being may, indeed, be designated 
 " speculative," and a turn may be given to the meaning of 
 the term intended to throw some discredit on the value of such 
 thinking, but the possibility of it is the matter to be explained. 
 A theory of the genesis of such thought is the first thing to be 
 supplied by the theorist who owns nothing higher than nerve 
 cells. No one can reasonably object to argument intended to 
 test the validity of thought involved in the recognition of the 
 Divine existence ; but the development of such criticism indi- 
 cates how real and how perplexing for the somatist is human 
 thought concerning the Absolute and Infinite. Conceptions of 
 the invisible) the infinite, the Divine, do exist in the world, 
 and they have exerted a wide influence in the history of the 
 human race. That this is simple statement of fact cannot be 
 denied ; the fact must somehow be explained ; the question is, 
 — Can a physiological explanation be offered ? 
 
 1 Des Cartes' Method ; Professor Veitch's translation, p. 76. 
 2 E 
 
434 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 If we inquire as to the intellectual conditions under which 
 such conceptions appear, we shall obtain further evidence con- 
 cerning the nature of the intelligence by which they are recog- 
 nised and rendered practically efficient for the guidance of life. 
 The mind concerns itself with the order of things as they con- 
 stitute an intelligible system, with their government and with 
 their origin, as things whose existence requires explanation. 
 The scientific thought which seeks to account for antecedence 
 and sequence in the physical world presents the type of 
 thought which widens the problem to embrace all existence, 
 and which desires rational explanation of it as a whole. That 
 explanation may be found in the invisible — must indeed be so 
 found, for this is the condition of the search, which has for 
 its object to explain the visible. There can be nothing alien 
 to scientific thought in this, unless it be unscientific to ask 
 for rational explanations of things known ; there is nothing at 
 variance with the accepted results of scientific thought which, 
 with full force of reason, as in recognition of the law of gravi- 
 tation, accepts the invisible as explaining the invisible.' The 
 thought which first classifies facts into distinct departments, 
 seeking to account for their occurrence, only proceeds a little 
 further in harmony with the same intellectual conditions, when 
 it seeks an explanation of all that belongs to the universe. The 
 " all things " may mean a much narrower range of fact for the 
 unscientific observer than for the scientific, but the intellectual 
 conditions of procedure are the same for scientific and unscien- 
 tific, and no feature of mental activity here falls to be explained 
 additional to that found in ordinary scientific thought. But 
 the demands of practical life lead directly to the prosecution of 
 such thought as bears on personal history. Moral life with its 
 law of rectitude, its obligations and responsibilities, has rela- 
 tions with a sphere of existence which transcends the visible. 
 At least so the moral agent commonly accounts of his life, and 
 that on the clearest rational grounds ; but the general fact is 
 here sufficient, as indicating that even the ordinary mind 
 raises the question as to the existence of an absolute autho- 
 rity controlling subordinate existence. This is an exercise which 
 must, therefore, be attributed either to the ordinary quality 
 1 For wider application, see The Unseen Universe. 
 
xiv.] THE HIGHER FORMS OF MENTAL ACTIVITY. 435 
 
 of brain, or to a mind which is superior to brain, and is the 
 common possession of men. 
 
 Further, the intelligence which raises the question concern- 
 ing the origin of things must find the solution in intelligence 
 of a higher order. This is clearly enough recognised by the 
 least educated mind, in accordance with the law of thought 
 which prevents us from regarding as a true cause anything 
 lower than the existence to be explained. Hence the most 
 uncivilised tribes, even with the most pitiful gathering of idols, 
 have never rested in an impersonal God. The least trained 
 among thinkers regard intelligence as an essential characteristic 
 of Deity. The intellectual warrant for this, merely in view of 
 the problem of existence, is beyond dispute. As Sir William 
 Hamilton has said, "We have only to infer, what analogy 
 entitles us to do, that intelligence holds the same relative 
 supremacy in the universe which it holds in us, and the first 
 positive cbndition of a Deity is established." 1 So, physical, 
 intellectual, and moral existence become harmonised in the 
 problem which intelligence raises as to the origin of the 
 universe. Contemplating in this way the totality of finite 
 existence, Dr. M'Cosh of Princeton has well said, "As the 
 physical requires the moral, so the moral requires the physical 
 as its complement, in giving a full exhibition of the character 
 of God, and of his administration in reference to our world." 2 
 
 Once more, in considering the mode in which the human 
 mind deals with the problem of existence, it must be observed 
 that everything finite is held to require an explanation of 
 its existence. This is seen to be true in the nature of the 
 case, apart from any rationalising process. The finite is the 
 dependent. Scientific thought cannot find a resting-place 
 for intelligence in "an infinite regress of finite causes" any 
 more than unscientific thought can find the explanation of 
 things in carved figures, named " gods," which are multiplied 
 for the use of families of a tribe. The conception of an infinite 
 series of dependent existences, which depend on nothing, or 
 depend only on one another, must be banished from the region 
 of scientific thought as incongruous. But it cannot disappear 
 without contributing its share of testimony to the fact that the 
 sic8, vol. i. p. 31. 2 Method 0/ the Divine Government, p. 448. 
 
436 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 human mind deals with the conception of the infinite, even 
 in attempting to construct the impossible combination of an 
 infinity of finite existences. Here, then, is a characteristic of 
 our thought, that the conception of the finite suggests the 
 conception of the infinite. And, though it is true that the 
 existence of an infinite and absolute Being is not the product of 
 a completed inductive process, the conception of such a Being 
 is familiar to the human mind, and is regarded as the only 
 rational explanation of existence, capable of rational vindica- 
 tion by convicting of irrationality every conceivable alterna- 
 tive, whether it be atheistic, pantheistic, or polytheistic. 
 
 In accordance with the view now given of the action of 
 human thought in dealing with the problem of existence, it is 
 established on amplest evidence that there is no tribe of men 
 ascertained to be destitute of religious belief, or without a 
 belief in a future state of existence for the soul. Dr. Edward 
 B. Tylor, in his work on Primitive Culture, has rendered great 
 service to the scientific study of human nature, as well as 
 the structure of a science of the religions of man, by accumu- 
 lating a mass of evidence drawn from all sources as to the 
 religious beliefs of uncivilised tribes. A great merit of Dr. 
 Tylor's work is that it presents evidence, apart from attempts 
 to show its harmony with accepted theory. Dealing with a 
 most complicated mass of testimony, Dr. Tylor seeks a general 
 characteristic of religious belief, applicable as a test to the 
 records of travellers, missionaries, and residents amongst the 
 lower races. He takes, " as a minimum definition of Beligion, 
 the belief in Spiritual Beings." 1 He says, "I propose here, 
 under the name of Animism, to investigate the deep- lying 
 doctrine of Spiritual Beings, which embodies the very essence 
 of Spiritualistic as opposed to Materialistic philosophy." 2 
 "Animism characterises tribes very low in the scale of 
 humanity, and thence ascends, deeply modified in its trans- 
 mission, but from first to last preserving an unbroken con- 
 tinuity, into the midst of high modern culture. ... It is 
 habitually found that the theory of Animism divides into two 
 great dogmas, forming parts of one consistent doctrine ; first, 
 concerning souls of individual creatures, capable of continued 
 
 1 Primitive Culture, vol. i. p. 424. 2 lb. vol. i. p. 425. 
 
xiv.] THE HIGHER FORMS OF MENTAL ACTIVITY. 437 
 
 existence after the death or destruction of the body ; second, 
 concerning other spirits, upward to the rank of powerful 
 deities." 1 "Thus Animism, in its full development, includes 
 the belief in souls and in a future state, in controlling deities 
 and subordinate spirits, these doctrines practically resulting in 
 some kind of active worship." 2 These quotations are sufficient 
 to show upon what basis Dr. Tylor rests his judgment. And 
 his testimony is the following : — " Here, so far as I can judge 
 from the immense mass of accessible evidence, we have to 
 admit that the belief in spiritual beings appears among all low 
 races with whom we have attained to thoroughly intimate ac- 
 quaintance; whereas the assertion of absence of such belief 
 must apply either to ancient tribes, or to more or less imper- 
 fectly described modem ones." 3 " Thus the assertion that rude 
 non-religious tribes have been known in actual existence, 
 though in theory possible, and perhaps in fact true, does not 
 at present rest on that sufficient proof which, for an exceptional 
 state of things, we are entitled to demand." 4 
 
 It is, therefore, in accordance with a vast mass of evidence 
 that Mr. Herbert Spencer speaks of the " omnipresence of the 
 beliefs," saying that "religious ideas of one kind or other 
 are almost if not quite universal." 5 These beliefs as to the 
 existence of Deity and a future existence for the soul may 
 with accuracy be described as " beliefs that are perennial, and 
 nearly or quite universal." 6 Excluding the apparent exception 
 of certain tribes, the following passage presents the competent 
 inference from the facts : " Grant that among all races who 
 have passed a certain stage of intellectual development, there 
 are found vague notions concerning the origin and hidden 
 nature of surrounding things; and there arises the inference 
 that such notions are necessary products of progressing intelli- 
 gence. Their endless variety serves but to strengthen this 
 conclusion, — showing, as it does, a more or less independent 
 genesis, — showing how, in different places and times, like con- 
 ditions have led to similar trains of thought, ending in ana- 
 logous results. That these countless different yet allied 
 
 1 Primitive, Culture, vol. i. p. 426. 2 lb. vol. i. p. 427. 
 
 3 lb. vol. i. p. 425. i lb. vol. i. p. 418. 
 
 6 First Principles, p. 13. 6 lb. p. 4. 
 
438 THE RELA TIONS OF MIND AND BRAIN. [chap. 
 
 phenomena presented by all religions are accidental or factitious, 
 is an untenable supposition. A candid examination of the 
 evidence quite negatives the doctrine maintained by some 
 that creeds are priestly inventions." 1 How much deeper 
 are human wants than the physical, appears in the universal 
 prevalence of religious belief and worship. It is no part of my 
 present task to form a strict estimate of the intellectual worth 
 of the several phases of religious belief found among the ruder 
 tribes of men. I do not deal with the vast variety of ex- 
 amples, so as to discriminate the rational substratum from 
 the irrational and incongruous admixture found in many. The 
 demands of the present argument do not make this needful. 
 I am not concerned with the measure of truth which may 
 belong to the beliefs of uncivilised tribes, but with the possi- 
 bility of such belief concerning Divine existence, and such 
 expectations of futurity of being as are found everywhere ex- 
 isting. In respect of these beliefs and expectations, it appears 
 that even the most barbarous tribes now existing are not far 
 removed from the level of religious creed which obtained 
 among the ancient Greeks and Eomans. And if such beliefs 
 and expectations are compatible with the lowest forms of un- 
 civilised life, and with an utter absence of education, the fact 
 presents a serious difficulty for a theory which assigns all 
 human activity to brain action alone, and makes the degree 
 of brain development the test of mental power. 
 
 On the other hand we must pass over to the lofty specula- 
 tion of philosophic thought, dealing with the very same 
 problems, and moving along the same lines as those indicated 
 when describing the thought of the lowest races, but rising 
 to speculations which many educated men cannot appreci- 
 ate. Whether we regard this higher range of thought as an 
 intellectual and moral reaction against the admixture of the 
 irrational and wicked with religious belief and practice, or as 
 a more purely speculative effort rising from the facts of the 
 universe, and aiming at the construction of a rationalised scheme 
 of existence, the testimony seems equally powerful in support 
 of a distinctly intelligent nature, having a field of action all its 
 own, and yielding results quite beyond those which can follow 
 
 1 First Principles, p. 13. 
 
xiv.] THE HIGHER FORMS OF MENTAL ACTIVITY. 439 
 
 from the functions of the most highly organised brain. Thus 
 we have the discriminating and massive thought of Socrates 
 seeking for the rational conceptions which should govern human 
 life j 1 and the protest of Plato againsjt the lies of the poets who 
 represented the gods to be deceivers and profligate; 2 and, far 
 away above this, his more adventurous speculation concerning 
 the essences of things, and the Good which is more than 
 essence, and the source of all. 3 In modern times we have the 
 whole movement of philosophic thought which has concerned 
 itself with the nature and functions of pure reason, presenting 
 the most marked severance from all that is involved in mere 
 sensibility and motor activity. That movement took, its rise 
 when Des Cartes sought self-knowledge in self-consciousness. 
 Its leading conception was indicated by Spinoza, when he pro- 
 claimed " what the true method must be, and wherein it chiefly 
 consists, viz., in a knowledge of pure intellect alone, its nature 
 and its laws." 4 Spinoza carried through his share of the move- 
 ment by seeking to deduce a complete scheme of the universe 
 from the conception of a self-existent, all-embracing unity. 
 Kant, by his critical method, went more rigidly in search of 
 what belongs to Pure Eeason itself, distinguishing between the 
 elements of knowledge which come through experience and 
 thbse which come from the mind itself, reaching thereby the 
 ideas of the soul, the universe, and God, as given by reason. 
 Hegel took the opposite direction from that of Spinoza, to 
 reach the same result, — from nothing by dialectic evolution 
 to obtain absolute unity in the true Infinite. To criticise these 
 schemes of thought, and estimate their philosophic value, 
 does not form any part of the present plan, any more than 
 to test the worth of the cruder thoughts of uncivilised men. 
 In so far as the foregoing investigations supply materials 
 for constructing a science of human life, they seem to make 
 it obvious that neither the scheme of Spinoza nor that of 
 Hegel can be accepted as a philosophy of existence, and that 
 the scheme of Kant, with the Categorical Imperative of Moral 
 Law as the central feature of an ethical system, is far more 
 
 1 Xenophon's Memorabilia, B. iv. ch. vi. 2 Republic, ii. 381. 
 
 3 lb. vi. 509. 
 
 4 Spinoza's Life, Correspondence, and Ethics, by Willis, p. 329. 
 
440 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 in accordance with the requirements of the problem to be 
 solved. But we are here concerned expressly with the fact 
 that such schemes of speculative thought are rational pro- 
 ducts of the human mind, affording profoundest interest to 
 very many who are occupied with the intellectual require- 
 ments of an adequate scheme of existence, or at least a scheme 
 so largely approximating to the great and obvious demands 
 of the problem of known existence, that it can be regarded 
 as entitled to rational credence. Here we find a typical 
 illustration of the highest efforts of human intelligence. We 
 witness the concentration of human thought on the problem 
 of being, the elaboration of an intellectual scheme in accord- 
 ance with human conceptions of the government of an in- 
 visible, infinite, and absolute Deity, under which government 
 moral excellence of conduct and holiness of character in man 
 are more in value than many worlds. In sight of such intel- 
 lectual exercise and its results, the conclusion seems beyond 
 dispute that the action and reaction of nerve tissue, mainly 
 concerned with the primary demands of sensation and motion, 
 can afford no explanation of the speculative thought which 
 occupies a, conspicuous place in literature. 
 
xv.] SUMMARY OF INTELLECTUAL RESULTS. 441 
 
 CHAPTER XV. 
 
 SUMMARY OF INTELLECTUAL RESULTS. 
 
 A brief outline will suffice for a summary of those forms of 
 activity -which illustrate the functions of mind as distinguishable 
 from those of brain. 
 
 Beginning with our experience as connected with sensation, 
 it is apparent that there are not only successive sensations, but 
 comparisons of the present sensation with some sensations pre- 
 viously experienced. In this way a knowledge of the qualities 
 of objects is obtained through our sensations, which could not 
 be attained without memory affording the materials, and judg- 
 ment discriminating between them. But specially, in each 
 phase of experience, there is a knowledge of Self, as distinct 
 from sensation ; and through the successive stages of experi- 
 ence there is a knowledge of Personal Identity, of the unity 
 of personal life, given in the voluntary use of memory, recall- 
 ing the facts of a past experience, and dealing with that past 
 as a unity in the whole course of which personal experience and 
 activity were involved. 
 
 When from the experience of sensation we pass to Motor 
 Activity, the aspect of personal existence is at once widened. 
 Quite apait from reflex action, or the automatic activity of 
 motor apparatus stimulated by the action of the sensory appa- 
 ratus, there is Self-originated action, or motor activity which 
 depends for its existence on our own intelligent purpose. In 
 this, the distinction between Self and the particular action of 
 the moment is preserved, as is the distinction between Self and 
 a sensation. In this case we know Self not only as affected by 
 objects belonging to an outer world, but as an agent in the 
 world, — the cause of personal activity, — an agent operating 
 according to the inner movement of an intelligent nature. And 
 here also, as well as in the other case, we have a knowledge of 
 
442 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 continuity of existence, — a knowledge of personal identity, 
 carrying with it personal responsibility for our conduct, con- 
 sidered in itself, and as bearing on the experience and activity 
 of other persons. 
 
 In harmony with what has been ascertained to be true of 
 the experience connected with sensation and motor activity, it 
 appears that there is a phase of personal activity in the exercise 
 of Memory as it provides for the recognised continuity of life, 
 combining successive forms of sensibility and activity. Such 
 exercise of memory cannot accurately be classified with motor 
 activity. Here it is needful to discriminate between what is 
 properly retentiveness, and what by contrast is more properly 
 recollection. Eetentiveness is not activity, but a product of 
 activity ; Recollection is a phase of activity, voluntary or in- 
 voluntary, resulting in an experience which is recognised by 
 the person as a reproduction or re-presentation of what has 
 previously had a place in experience. So far as observation 
 testifies, Recollection, in this sense, does not illustrate any 
 phase of motor activity, and obviously is not connected with 
 any muscular action, such as depends upon the motor nerves. 
 In its highest and most striking forms, it illustrates the action 
 of Intelligence and of Will. Under the laws of association, 
 there may indeed be involuntary recollection. But it is the 
 voluntary activity involved in recollection which most engages 
 our attention here. There is a voluntary storing and a volun- 
 tary recalling, for both of which a distinct exercise of intelli- 
 gence is needful. The knowledge which is surely stored must 
 be the object of careful discrimination ; the action of recollec- 
 tion, which makes such knowledge available in the history of 
 personal life, implies intelligent use of the distinctions pre- 
 viously recognised, and personal application of the laws of 
 association for the end contemplated. While animal tissue 
 carries within it the impress of past activity, intelligence 
 directs its own power for renewed use of materials previously 
 accumulated, and it does so according to a plan, and for ends 
 which intelligence alone can appreciate. 
 
 In these three outstanding facts, intelligent use of sensi- 
 bility (including the different forms of it belonging to the 
 special senses) ; intelligent direction of motor activity ; and. 
 
xv.] SUMMARY OF INTELLECTUAL RESULTS. 443 
 
 intelligent use of a power of recollection, we have the distin- 
 guishing features of the early stage of human life. We see in 
 these the immense superiority of the child over all lower orders 
 of animate existence. The distinction consists in this, that 
 the child's life is a personal life. From the first he thinks and 
 speaks of Self as the centre of a circumference of knowledge 
 and activity. In harmony with this, the recollections of his 
 past life are constantly referred to, and they contribute an 
 essential and important element in all the interest which 
 attaches to the present, as well as in the direction of fresh 
 activity. The expectations of the future are cherished in 
 accordance with the same conditions. It is a personal future 
 which is anticipated, for which personal preparation is made, 
 and in view of the possibilities of which plans are devised 
 which take account of life as a whole. 
 
 This life is seen to widen and deepen largely under the 
 additional advantages which Speech implies. In a child's life, 
 the vocal organs are used as the expression of personal life, 
 and language becomes the medium of nourishment for such a 
 life. The thought which arises from the intelligent use of the 
 senses is rectified and expanded by the guidance which comes 
 through interpretation of the words of others. Speech is thus 
 an index to the power of intelligence within the child, and an 
 instrument for development of the intelligence which its use 
 presupposes. In the acquisition of language, the child becomes 
 the heir of preceding ages of intelligence. There is no need to 
 linger at this point for comparison with animals. The contrast 
 is too obvious to need illustration. The immense advantage 
 implied in the intelligent use of language is manifest. This 
 appears in the vast range of significance which we attribute to 
 Education. We may truly say that the senses are the primary 
 educators. But the senses have their influence in this direc- 
 tion multiplied incalculably, by association with vocal organs, 
 and with all that is involved in their intelligent use. Eye and 
 ear contribute a thousand times more towards the enriching 
 of personal life than is involved in mere sensory impressions, 
 by the use which, through their instrumentality, intelligence 
 can make of literature, and of converse with others who 
 are observers and thinkers. Intelligence makes the senses 
 
444 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 instruments of knowledge in a much higher degree than they 
 are by their mere natural functions. Eye and ear do unspeak- 
 ably more for intelligent life than for animal life. And this we 
 must interpret by saying that intelligent life puts the senses to 
 wider use than is involved in all the requirements of animal 
 life. There is, besides, an exercise of speech, which places it 
 in advance of the senses among instruments of knowledge. 
 While in personal life the senses afford ingress to intelligence, 
 Speech affords egress for intelligence, which is quickened and 
 strengthened by expression of thought. There is here an im- 
 mense advantage in the history of personal life. To be dumb 
 is to be restricted to a more contracted range of intelligent 
 activity. Hence physical defect connected with the vocal 
 organs is made up for by use of visible signs, which are the 
 contrivances of intelligence to overcome the disadvantages of 
 physical restraint. The need of the intelligent nature for 
 expression is thus made more manifest, and we are thereby 
 taught the better to estimate important advantages which 
 are apt to be overlooked by us, on account of our familiarity 
 with them. Speech is primarily a physical acquisition, but is 
 in reality an intellectual attainment, and it is thereafter an 
 instrument by use of which provision is made for action and 
 reaction of mind upon mind L in a community of intelligent 
 beings. 
 
 The higher significance of personal life appears, when next 
 we contemplate the self-regulated life of man in all its leading 
 phases. The contrast from early life is seen even in the govern- 
 ment of external conduct, but is manifested most of all in the 
 concentrated intellectual effort of the inner life. Such effort 
 is characteristic in varying degrees of all men, from the un- 
 educated to the most scientific and philosophic. The possi- 
 bilities of human life are to be measured by the possible 
 concentration of thought ; its achievements by the degree in 
 which such concentration has been attained. From lack of con- 
 centration, all the possibilities of high brain development have 
 been associated with a dissipation of mental energy, resulting in 
 a life which could not be described otherwise than as a failure, 
 physical existence itself being cut short in premature death. 
 By means of concentration of thought, the physical life, which 
 
xv.] SUMMARY OF INTELLECTUAL RESULTS. 44S 
 
 has been checked in development by many disadvantages, has 
 been united with a mental life showing large appreciation of 
 the higher laws of self-regulation, and presenting triumphs 
 of self-mastery, which bodily infirmities make only more 
 conspicuous. 
 
 The study of humanity thus requires that full account be 
 made of the conditions and achievements of intellectual 
 activity. The conditions of thought present the essential 
 characteristics of personal life ; its highest ranges afford some 
 measurement of the possibilities of an intelligent nature ; its 
 history represents the continuity of rational power in the 
 world. If the multifarious illustrations of intellectual activity 
 be gathered into departments, the evidence is more readily 
 appreciated. And the more closely we keep to the common 
 characteristics of men, the more compactly can we gather into 
 unity the contributory portions of evidence. In view of these 
 considerations, there is value in turning attention singly to the 
 purely intellectual, the moral, and the religious applications of 
 intelligence, and afterwards gathering up a united representa- 
 tion of the normal type of intelligent life. 
 
 One large department of mental activity is concerned with 
 the understanding of things around us. Scientific inquiry is 
 the highest and best example of that outgoing of human 
 understanding which is a common exercise for every member 
 of the race. To compare, to discriminate, to classify, to 
 generalise, all these are exercises common to intelligent life. 
 And all of them imply voluntary concentration on the facts 
 observed. A power of self-regulation is brought into action, 
 which determines the progress of thought, and is the true 
 explanation of the widening area of knowledge which becomes 
 a personal possession. 
 
 A second department of intellectual activity is concerned 
 with the regulation of personal life itself, in all the aspects of 
 personal conduct, including as the key to the whole the govern- 
 ment of the motive forces belonging to our nature, physical and 
 mental. Human nature is a unity, and so also is human life, 
 to be regulated by the imperative implied in moral law, as the 
 supreme law of life. The greatness of human life appears in 
 the degree in which moral law holds sway over it, and spreads 
 
446 THE RELATIONS OF MIND AND BRAIN. [chap. 
 
 from it an influence which encourages and helps others in 
 the attainment of similar excellence. In order to effect this, 
 the essential requisite is individual reflection, turned from the 
 inducements afforded by outward opportunities and physical 
 sensibilities, and directed upon rational law, which is law for 
 the individual, only as it is law for all men, affording the test 
 equally of what ought to be done by the thinker, and what is 
 to be expected from other rational agents. 
 
 A third department of intellectual activity is that which 
 seeks an explanation of the universe as a whole, and a view of 
 the responsibility and destiny of the rational being, in accord- 
 ance with the recognised superiority of moral life. This is a 
 range of thought which owes its procedure to the acknowledg- 
 ment that all finite existence needs explanation, and that of 
 finite existence, moral being, as the highest known to us, pre- 
 sents the governing consideration in rational treatment of the 
 problem as to the origin of the universe. As all finite exist- 
 ence needs explanation, the rational nature which seeks it can 
 find it only in an Absolute Being, of infinite intelligence and 
 absolute moral excellence. In recognition of these intellectual 
 requirements, we find among all races of men the acknow- 
 ledgment of a sovereign ruler, and the expectation of future 
 existence. 
 
 When these three departments of intellectual activity are 
 combined for a united view of intelligent life, we see how 
 much the history of such life depends on voluntary reflection 
 according to recognised rational law. Individual thought in- 
 terprets the impressions which come to us through the senses, 
 and seeks a rational solution of the problems which these im- 
 pressions occasion. The moral agent considers the requirements 
 of a rational law of life, standing in opposition to the impulse 
 of blind desire. Beyond this, thought rises from the order 
 existing in the universe to the government of an invisible hut 
 infinite and absolute God, of whose nature the laws of our moral 
 life are the best index, and under whose rule the prospect of a 
 future state of being may be reasonably cherished. This vast 
 range of intellectual activity must either be brought within the 
 compass of the recognised functions of brain, or it must he 
 acknowledged as beyond dispute that there belongs to man a 
 
xv.] SUMMARY OF INTELLECTUAL RESULTS. 447 
 
 nature of higher and nobler type, which we designate Mind. 
 The most advanced results of physiological science afford us 
 no philosophy of these facts ; whereas the results of psycho- 
 logical inquiry imply the possession of a nature higher than 
 the physical. 
 
 I do not press the question as to the nature of Mind 
 beyond ascertaining its functions. That nature is clearly 
 enough indicated when its functions are shown to be essen- 
 tially different from those of brain, and altogether higher in 
 kind. Mind cannot be explained under the conditions appli- 
 cable to matter. The immateriality of the rational nature is 
 clearly implied in the forms of activity which are peculiar 
 to it. There is no call specially to insist upon this, as if 
 it involved anything of moment as to the future destiny of 
 mind. Futurity of being is not dependent upon the nature 
 of the existence, whether it be material existence or imma- 
 terial ; the ground for expectation of a future beyond the 
 grave is the subjection of life to moral law, and all that this 
 involves. That there is much in the nature of mind greatly 
 beyond our understanding may be freely granted. This has 
 been felt and recognised by the physiologist and pathologist, 
 as may be seen from these striking words of Dr. Maudsley : — 
 " Entirely ignorant as we are, and probably ever shall be, of 
 the nature of mind, groping feebly for the laws of its operation, 
 we certainly cannot venture to set bounds to its power over 
 those intimate and insensible molecular movements which are 
 the basis of all our visible bodily functions, any more than we 
 can justly venture to set bounds to its action in the vast and 
 ever progressing evolution of nature of which all our thoughts 
 and works are but a part. ... In the microcosm of the body, 
 which some ignorantly despise there are many more things in 
 reciprocal action of mind and organic element than are yet 
 dreamt of in our philosophy." 1 No competent philosophy will 
 despise the body, or set lightly on man's relation to Nature, 
 meaning by that term the great Kosmos of which we form 
 a part. But, if man's nature is the greatest thing within 
 the circle of our observation, it is the rational life of man 
 which constitutes his greatness. If there be a rational element 
 1 Body and Mind, p. 38. 
 
448 THE RELATIONS OF MIND AND BRAIN. [chap. xv. 
 
 everywhere in nature, it is the intellectual power of man which 
 detects it, and elaborates a system of the universe. Not with- 
 out sufficient reason is man's own nature regarded as a micro- 
 cosm, representing the material and the mental, — physical 
 organism and rational life. His life is representative of the 
 whole, as is no lower order of life. For whatever we say 
 of the "intelligence" of animals, or with whatever warrant 
 " mind " is attributed to them, theirs is at least a lower order 
 of " mind," and not such as can recognise the rational in the 
 system of the wide universe. Man looks abroad upon the 
 whole, and delights in discovering the rational on all sides. 
 He does more. Contemplating his own nature, and cherish- 
 ing rational expectation as to a great futurity, he anticipates the 
 continuance of his life, as he distinguishes between a perishable 
 and an imperishable. In doing so, he beholds in his own life 
 a twofold continuity. There is a life of the body, which is 
 progressive from youth to maturity, and after that still ad- 
 vances, but by way of decline, downwards to decay, preparing 
 for decease. There is a life of the mind, which is progressive 
 as life advances, and even after physical maturity is past, pro- 
 gressive in respect of enlarging knowledge, loftier attainment, 
 and clearer expectation of a life bordered by no dark shadow of 
 death. In harmony with the expectations which moral life 
 inspires, the philosophic spirit has said, — " there is a change 
 and migration of the soul from this world to another," — in 
 accordance with which it could utter these words of counsel, — 
 " Know this of a truth, that no evil can happen to a good man, 
 either in life or in death." 1 And still more fully in harmony 
 rejoicing in a clearer light, is that wide and grateful welcome 
 which Christianity has had among men, bringing, as it has 
 done, "life and immortality to light through the gospel," — 
 recognising that Science and Philosophy must be achievements 
 of men, while God Himself gives direct testimony to the race 
 concerning an immortality beyond the visible. 
 1 Plato's Apology, 40, 41. 
 
INDEX. 
 
 ASbrceombib, weight of his brain, 23 ; 
 thought in sleep, 345 ; sleep during 
 work, 353 ; case of brain activity 
 during sleep, 403. 
 
 Accidental injuries to brain, 393. 
 
 Acquisitions, physical and mental, 265 ; 
 numerical calculations as to, 277. 
 
 Action and reaction of Body and Mind, 
 313. 
 
 Action of Brain commonly attendant on 
 Mental activity, 328. 
 
 Afferent nerves, 44. 
 
 Agassiz, weight of his brain, 23. 
 
 "American Crow-bar case," 51 ; mental 
 results from the injury, 397. 
 
 Angle'sey,Lord, escape from suffering, 324. 
 
 Animal tissue, contractility of, 251. 
 
 Ape, brain of, 154; habits of, 156166 ; 
 
 brain of, compared with brain of idiot, 
 
 161 ; with ordinary human brain, 163 ; 
 
 likeness of ape to man in physical struc- 
 
 ' ture, 164; intelligence of, 165. 
 
 Aphasia, nature of, 304 ; illustrates rela- 
 tion of Intelligence to Speech, 305 ; 
 examples of, 305-312. 
 
 Arachnoid mater, 12. 
 
 Aristotle's view of practical life, 424. 
 
 Auditory nerve, 69. 
 
 Babbage, weight of his brain, 23. 
 
 Bain, Prof., his theory of memory, 272, 
 278 ; man a double-faced unity, 216, 
 315 ; change necessary to conscious- 
 ness, 218. 
 
 Basal ganglia, 32. 
 
 Bastin, Dr., discrimination of effects of in- 
 jury to brain, 383; relation of posterior 
 lobes to intellectual activity, 400. 
 
 Bateman on Aphasia, 304; case of, 311. 
 
 Battell, Andrew, on the ape's intelli- 
 gence, 168. 
 
 Beauty, sense of, as related to the Eye 
 and to Intelligence, 231. 
 
 Bell, Sir Charles, researches of, 42 ; on 
 
 2 
 
 muscles and nerves, 45 ; removal of 
 parts of brain, 51 ; distinction between 
 nerves of sensation and of motion, 79 ; 
 out-door exercise and brain develop- 
 ment, 421. 
 
 Bennett, Professor, on power of imagi- 
 nation as to suffering, 323. 
 
 Betz on nerve cells, 27. 
 
 Bischoff on brain of ape and of man, 8 ; 
 mean weight of ape's brain, 14; case of 
 microcephaly, 372. 
 
 Blind man distinguishing coloured 
 fabrics, 55. 
 
 Blood-supply for the brain, 37. 
 
 Bodily condition, influence of, upon In- 
 tellect, 315 ; somatist argument based 
 on this, 316 ; negative positions in the 
 argument, 318. 
 
 Body, influence of mind upon, 319. 
 
 Boll, F., on sight-purple, 65. 
 
 Brain (Human), coverings of, 11 ; situa- 
 tion of, 12 ; size, 12 ; weight, 13 ; 
 configuration, 14 ; fissures in, 14-15 ; 
 lobes, 15 ; hemispheres of, 16 ; upper 
 surface of, 17 ; size and weight of, not 
 always associated with high intellectual 
 power, 20 ; difference of weight of, in 
 male and female, 21 ; convolutions, 
 18 ; internal structure, 24 ; lower sur- 
 face, 34 ; an organ in two halves, 204 ; 
 superiority of, 208 ; no consciousness 
 of its existence, 212; disorders of, 362. 
 
 Brain, similarity of structure in all animal 
 life, 187. 
 
 Brain action commonly attendant on 
 mental activity, 329. 
 
 Brain development as connected with 
 muscular, 206. 
 
 Brain Disorders, 362 ; improperly named 
 " mental diseases," 363 ; imperfect 
 development of brain, 365 ; imbecility, 
 366 ; microcephaly, 367 ; examples, 
 36"8 ; disease of brain, 375 ; paralysis, 
 383 ; mental experience occasioned by 
 
450 
 
 INDEX. 
 
 brain disease, 384 ; treatment of in- 
 sanity, 387 ; violent injury to the 
 healthy brain, 393 ; how insanity may 
 be induced, 402 ; how averted, 409. 
 
 Brain work, and the weariness which it 
 induces, 326; difference between, and 
 mental work, 327. 
 
 Bridgman, Laura, case of, 296. 
 
 Broca on Aphasia, 288 ; connected with 
 left hemisphere, 304 ; case of, 309. 
 
 Brown, Prof. Crum, on rotatory motion 
 as affecting the semicircular canals of 
 the ear, 73. 
 
 Brown, Br. John, on superiority of the 
 dog among animals, 137. 
 
 Brown-Sequard, on pathological aspects 
 of brain injury, 365. 
 
 Browne, Dr., on impairment of speech, 
 305 ; case of, 30S ; cure of brain wast- 
 ing, 383 ; small amount of thought in 
 ordinary work, 385 ; effects of emotion 
 on brain, 387. 
 
 Burdon-Sanderson, Dr., on electric exci- 
 tation of brain, 105. 
 
 Braun on incision into grey matter, 105. 
 
 Bruer on rotatory motion, 73. 
 
 Buckland, Francis T., on foot of the 
 monkey, 90. 
 
 Buffon on intelligence of the ape, 170. 
 
 Cai/derwood, Be v. H., on intelligence of 
 horse, 144. 
 
 Campbell, Lord, weight of his brain, 
 23. 
 
 Cardonna's (Prof.), case of microcephaly, 
 369. 
 
 Carp, brain of, 125. 
 
 Carpenter on reunion of parts of a cut 
 nerve, 52 ; diameter of nerve fibre, 
 63; unconscious cerebration, 116; on 
 Ascidian Mollusk, 123 ; on " lip-read- 
 ing," 293. 
 
 Carville and Duret's experiments, 82, 
 104. 
 
 Cat, brain of, 132. 
 
 Cells of the grey matter, 25 ; different 
 forms of, 26 ; their aspects in different 
 layers of the grey matter, 27 ; action 
 of, 193. 
 
 Central lobe, 35. 
 
 Centres ot sensation and motion in the 
 brain of the monkey, 86 ; of the dog, 
 97. 
 
 Cerebellum, functions of, 163. 
 
 Chalmers, weight of his brain, 23. 
 
 Chimpanzee, weight of brain of, 13 ; 
 structure of, 159. 
 
 Christison, Sir Robert, report on the 
 brain of Lord Jeffrey, 23. 
 
 Clarke, Dr. Lockhart, on nerve cells, 27. 
 
 Clouston, Dr., examples of disordered 
 brain, 377. 
 
 Comparative brain structure : brain of 
 carp, 125 ; of frog, 127 ; of pigeon, 
 127 ; of rat, 129 ; of rabbit, 130 ; of 
 cat, 132 ; of dog, 133; of horse, 141 ; of 
 monkey, 150; of ape, 154; of man, 152, 
 155 ; of elephant, 175 ; of whale, 181. 
 
 Conceptions, 223 ; their relation to per- 
 ception and to brain, 223. 
 
 Configuration of the brain, 14. 
 
 Connecting band uniting the two hemi- 
 spheres of the brain, 29. 
 
 Consciousness, reliability of, 4. 
 
 Contractility of muscular tissue, 79, 251. 
 
 Convolutions of grey matter, differently 
 arranged in the two hemispheres, 19 ; 
 complexity of, 23. 
 
 Cornea, 60. 
 
 Corpus callosum, 29 ; absence of, 372. 
 
 Corpus striatum, 31. 
 
 Corpuscles connected with nerves of 
 touch, 42 ; sensitiveness of, 192. 
 
 Cranial nerves, 39. 
 
 Crystalline lens, 61. 
 
 Cutting a nerve fibre, effects of, 52. 
 
 Cuvier, weight of his brain, 23. 
 
 Darwin on brain as the measure of 
 mind, 8. 
 
 Davis, Dr. Barnard, on diversity of 
 cranium with different races, 367. 
 
 Dax on loss of speech, 304. 
 
 Deaf-mutes, education of, 292 ; examples 
 of, 295. 
 
 De Morny, weight of his brain, 23. 
 
 De Quincey, tendencies in dreaming, 342. 
 
 Des Cartes on our conception of an Ab- 
 solute Being, 433. 
 
 Dickens on Laura Bridgman's ease, 298. 
 
 Dirichlet, weight of his brain, 23. 
 
 Discrimination essential to human ex- 
 perience, 220. 
 
 Disturbed bodily condition, influence on 
 mind, 315. 
 
 Divine existence, recognition of, 435 ; 
 relation of physical and moral exist- 
 ence to, 435. 
 
 Dodds, Dr., on localisation of functions, 
 1 04 ; anatomical aspects of the ques- 
 
INDEX. 
 
 45' 
 
 tion, 105 ; on structure of grey matter, 
 106 ; pathological results, as bearing 
 on localisation, 109 ; sensory and 
 motor centres, 112 ; direction of nerves, 
 117. 
 
 Dog, brain of, 134; electric excitation 
 of, 99 ; intelligence and affection of, 
 137-140 ; compared with horse, 145. 
 
 Dreaming, phenomena of, 334 ; influence 
 of excited brain condition, 334 ; not 
 connected exclusively with the begin- 
 ning of sleep, and waking from it, 
 335 ; recollection not a test of, 336 ; 
 the part of Imagination in, 338 ; vo- 
 luntary determination, 340 ; intellec- 
 tual activity, 342 ; theories of, 343 ; 
 examples of dreams, 344 ; general con- 
 clusions, 347. 
 
 Du.Chaillu on the gorilla, 158. 
 
 Duncan, Dr., on influence qf drunken- 
 ness in inducing brain disorder, 382. 
 
 Dura mater, 11. 
 
 Eak, the, its structure, 70 ; the three 
 chambers, 70-71. 
 
 Efferent nerves, 43. 
 
 Electric excitation of the brain, 81 ; mode 
 of experiment, 83 ; positive results, 
 86 ; interpretation, 107 ; " negative 
 results," 117, 254; interpretation of, 
 209. 
 
 Elephant, brain of, 175 ; strength of, 
 176 ; disposition of, 179 ; intelligence 
 of, 179. 
 
 Emotion, power of, over the body, 321. 
 
 English words, number of, 277. 
 
 Excision of grey matter of brain, 105. 
 
 Exhaustion of brain, 50. 
 
 Experience, personal, as conpected with 
 sensation, 213 ; motor activity, 238 ; 
 recollection, 282 ; use of speech, 301 ; 
 weariness, 329. 
 
 Eye, the, as it illustrates intelligence, 
 228 ; the guide of man, as it is not of 
 animals, 229 ; its relation to the beau- 
 tiful, 231. 
 
 Eyeball, structure of, 60. 
 
 Facility in use of a nerve fibre, 55. 
 
 Eear, influence of, on the body, 322. 
 
 Fechner's law, 57. 
 
 Feeling," Eenewed, its physical condi- 
 tions, 272. 
 
 Ferrier, Dr., on American Crow-bar case, 
 51 ; more fully, 395 ; on electric ex- 
 
 citation of brain, 82 ; on localisation 
 of functions, 83 ; experiments on brain 
 of monkey, 84 ; of dog, 99 ; of rat, 
 130; functions of cerebellum, 164; 
 molecular changes in the brain, ] 95 ; 
 on the brain as an organ of two halves, 
 204 ; on cerebral disease, 364 ; lesions 
 of brain, without mental symptoms, 
 384, 399. 
 
 Feuchtersleben on represented images of 
 objects, 363. 
 
 Fibrous tissue in the brain, 27. 
 
 Fissures in the brain, 14-15. 
 
 Fleming, Rev. John, on the Narwal, 
 185. 
 
 Force, Professor Tait, on, 200. 
 
 Frequency of use of a nerve fibre, 53. 
 
 Fritsch and Hitzig's experiments, 81. 
 
 Frog, brain of, 127. 
 
 Frontal lobes penetrated, two cases of, 
 395. 
 
 Fuchs, weight of his brain, 23. 
 
 Functional activity pi the nerves, 47. 
 
 Gamgee on sight-purple, 65. 
 
 Gauss, Professor, figure of the brain of, 
 17 ; weight of his br.ain, 23. 
 
 Goltz on localisation, 104. 
 
 Goodsir, weight of his brain, 23. 
 
 Gore, Mr., case of microcephaly, 370. 
 
 Gorilla, habits of, 1.58 ; brain of, 159. 
 
 Grandoni, Antonia, case of, 369. 
 
 Gratiolet's arrangement of lobes, 17 ; 
 order of their devolppmenj;, 162. 
 
 Graves, Dr., on loss of speech, 307. 
 
 Grey matter of the brain, 25 ; not sensi- 
 tive to touch, 51. 
 
 Grey and white matter, their relation in 
 the spinal cord, 40. 
 
 Growth of the brain, 12. 
 
 Haegkel on primary elements of expe- 
 rience, 220. 
 
 Hall, Marshall, on reflex action, 80. 
 
 Halle on form of convolutions, 24. 
 
 Bailer on contractility of muscular tissue, 
 79. 
 
 Hamiltpn, Sir W., on memory, 270 ; on 
 recognition of Divine existence, 435. 
 
 Hearing as a form of sensation, 233. 
 
 Heinicke on instruction of deaf-mutes, 
 292. 
 
 Helmholtz on transmission of influence 
 along nerves, 58. 
 
 Hemispheres, two, in the brain, 12 ; 
 
45 2 
 
 INDEX. 
 
 separation of the two, 16 ; the con- 
 necting tissue which unites them, 29 ; 
 different arrangement of convolutions 
 in the two, 19 ; functions of, 204. 
 
 Henderson, Professor, example of idiot's 
 brain, 162. 
 
 Hermann on incision into grey matter, 
 105. 
 
 Higher forms of mental activity, 411 ; 
 purely intellectual department of 
 thought, 414 ; thought concerned with 
 regulation of personal life, 423 ; con- 
 cerned with the Absolute Being and 
 His government, 432. 
 
 Horse, brain of, 141 ; intelligence of, 
 142-144 ; compared with dog, 145. 
 
 Howe, Dr., on case of Laura Bridgman, 
 296. 
 
 Huxley on resemblance of the brain of 
 the ape and of man, 154 ; prominent 
 distinctions, 161 ; on nest of the or#ng, 
 167 ; intelligence of ape, 168 ; on 
 Buffon and Linnaeus, 170 ; comparison 
 of the brain structure, and activity of 
 the ape, 173. 
 
 Imaginary suffering, 323. 
 
 Imagination, power of, to induce sensa- 
 tion, 323 ; exercised during sleep, 338. 
 
 Imbecility, 366. 
 
 Insane, bearing of their experience on 
 reliability of consciousness, 5. 
 
 Insanity, 384 ; treatment of, 387 ; how 
 induced, 402 ; how averted, 409. 
 
 Intellect, relation of, to brain develop- 
 ment, 19 ; great, associated with large 
 brain, 23. 
 
 Intellectual action during sleep, 342. 
 
 Iutelligent interest, power of, in relation 
 to the body, 324. 
 
 Introspection, objections made against, 6. 
 
 " Involuntary muscles," 259. 
 
 Ireland, Dr., on co-operation of conscious 
 activity, with unconsciqus cerebration, 
 116; circumference of cranium in 
 idiots, 367 ; idiocy as result of micro- 
 cephaly, 367 ; on education of idiots, 
 371 ; combination of physical and 
 mental training, 374. 
 
 Jackson, Dr. Hughlings, on loss of 
 speech, 305. 
 
 Dr. S., on loss of speeoh, 306. 
 
 Jeffrey, Lord, weight of his brain, 23. 
 Jones, J. Handfield, on trance, 357. 
 
 Kuhnb, W., on sight purple, 65. 
 
 Kussmaul on tests of psychical action, 
 287 ; vocal apparatus, 288 ; relation 
 of deafness to speech, 292 ; case of a 
 deaf-mute, 295 ; instruction of deaf- 
 mutes, 299. 
 
 Labyrinth of the ear, 73. 
 
 Laceration of frontal lobes, without 
 mental symptoms, 399. 
 
 Lancet, on central lobe {insula), 16. 
 
 Language, relation of, to thought, 330. 
 
 Laura Bridgman, case of (deaf-mute and 
 blind), 296. 
 
 Laycock on unconscious cerebration, 
 116. 
 
 Lewes, Gr. H., on the relation of sensi- 
 bility to consciousness, 213. 
 
 " Lip-reading," 293-299. 
 
 Lister and Turner on chemical composi- 
 tion of nerve fibre, 28. 
 
 Lobes in the brain, 15 ; order of their 
 development in the brain of man and 
 of the ape, 162. 
 
 Localisation of Functions in the Brain, 
 77 ; investigations by Fritsch and 
 Hitzig, 81 ; by Dr. Ferrier, 82; as to 
 brain of monkey, 84 ; of dog, 99. 
 
 Locke, John, on dreaming, 343. 
 
 Lotze, Hermann, on unity of conscious- 
 ness, 283. 
 
 Mach on rotatory motion, 73. 
 
 M'Cosh, President, on evidence for exist- 
 ence of Deity, 437. 
 
 M'Kendrick on transmission of nerve 
 influence, 58 ; on brain of pigeon, 
 128. 
 
 Major, H. C, on central lobe (insula), 
 16 ; relation of intellect to brain de- 
 velopment, 20 ; new method of deter- 
 mining depth of grey matter, 25 ; 
 distribution of cells in the grey matter, 
 27 ; estimate of intellect by examina- 
 tion of brain, 421. 
 
 Malinverni, Prof., on case of absence of 
 corpus callosum, 372. 
 
 Man, brain of, 12; right hemisphere, 
 14 ; left hemisphere, 152 ; upper sur- 
 face, 17 ; convolutions in, 18 ; internal 
 structure, 24 ; union of hemispheres, 
 30 ; basal ganglia, 32 ; lower surface, 
 34 ; lower divisions of nerve centre, 35. 
 
 Marsh, G. P., on number of English 
 words, 277. 
 
INDEX. 
 
 453 
 
 Marshall, Prof., on weight of ape's 
 brain, 14 ; on brain of chimpanzee, 
 159, 160 ; comparison of brain of apes 
 and idiots, 371. 
 
 Masson, Professor, on vocabulary of 
 Shakespeare and Milton, 277. 
 
 Maudsley on consciousness, 4; intro- 
 spection, 6 ; weight of brain, 23 ; no 
 consciousness of the existence of brain, 
 212; relation of mental development 
 to muscular action, 366 ; heredity as 
 bearing on insanity, 381 ; treatment 
 of insane, 391 ; responsibility for in- 
 sanity, 409 ; our ignorance of the 
 nature of miDd, 447. 
 
 Medulla oblongata, 36. 
 
 Membranes which cover the brain, 11- 
 12. 
 
 Memory, laws of, 262 ; distinction be- 
 tween physical and mental, 268. 
 
 Mental activity, its more common accom- 
 paniments of brain activity, 328 ; its 
 possibility during sleep, 334 ; higher 
 forms of, 411. 
 
 " Mental diseases " a misnomer, 363. 
 
 Mental experience under brain disease, 
 384. 
 
 Mental phenomena provisionally defined, 
 9. 
 
 " Mesmeric sleep," 359. 
 
 Meynert on the brain of the ape, 160. 
 
 Mezzofanti, his knowledge of languages, 
 277 ; loss of this in fever, 305 ; tem- 
 porary unconsciousness, 351. 
 
 Mill, James, on experience as a series of 
 smells, 13f. 
 
 Mill, J. S., on analysis of consciousness, 
 214; on mind as a series of feelings, 
 225. 
 
 Milton, vocabulary of, 279. 
 
 Mind not a phase of matter, 216 ; not a 
 series of feelings, 225 ; influence of, 
 upon Body, 319. 
 
 Molecular changes in the grey matter, 50. 
 
 Monkey, brain of, 150; electric excita- 
 tion of, 86. 
 
 Moral life and its guidance, 423 ; differ- 
 ence between man and animal in this 
 respect, 425. 
 
 Motor nerves, 41 ; apparatus, 189 ; 
 activity of, 197 ; rest of, in sleep, 333. 
 
 Motor activity as influencing experience, 
 
 237. 
 Miiller on conducting power of nerve 
 fibre, 53; control over groups of 
 
 muscles, 57 ; Purkinje's experiment as 
 to retina, 65, 67. 
 
 Miiller, Max, testimony of language to 
 intelligence, 287 ; relation of speech 
 to reason, 300. 
 
 Muscular activity, 201. 
 
 Muscular development as connected with 
 brain development, 206. 
 
 Muscular tissue, contractility of, 79. 
 
 Music, as it affects man and animals, 
 233. 
 
 Musical composition as related to sensi- 
 bility and intelligence, 234. 
 
 Musical execution during sleep, — imita- 
 tion of violin, 403. 
 
 Nerves, their structure, separation, and 
 connection, 28 ; connecting grey mat- 
 ter of opposite hemispheres, 31 ; dis r 
 tinction between sensory and motor, 
 79. 
 
 Serves of special sense, 39. 
 
 Nerve glue, 25. 
 
 Nerve cells, 25 ; difficulty of attributing 
 memory to, 275. 
 
 Nerve centre, distinctive feature of, 47. 
 
 Nerve fibres, similarity of structure in 
 all animals, 187. 
 
 Neurology, New York Society of, 82, 
 104. 
 
 New York Society of Neurology and 
 Electrology, 82, 104. 
 
 Noble, Dr., on the power of imagination 
 during suffering, 323. 
 
 Nothnagel on characteristics of epilepsy, 
 377 ; case of epilepsy, 393. 
 
 OrTic apparatus, 60 ; optic nerve, 61. 
 
 Optic thalamus, 32. 
 
 Orang, weight of brain of, 13 ; habits of, 
 158 ; structure of brain, 159 ; intelli- 
 gence of, 167-168. 
 
 Owen, Professor, on weight of brain of 
 chimpanzee, 14. 
 
 Pacini, corpuscles of, 42. 
 
 Page, H. A., on De Quincey's dreaming, 
 343. 
 
 Paralysis, 383. 
 
 Perception, how distinguished from sen- 
 sation, 222 ; involves judgment, 223. 
 
 Personal determination as concerned with 
 motor activity, 241 ; as exercised dur- 
 ing sleep, 340. 
 
454 
 
 INDEX. 
 
 Personality, as illustrated by sensation, 
 222 ; by motor activity, 242. 
 
 Pla mater, 12. 
 
 Pigeon, brain of, 127. 
 
 Philosophy and science, relations of, l r 3. 
 
 Plato, his doctrine of reminiscence, 266 ; 
 relation of soul and body, 320 ; on 
 misrepresentation of the gods, 439 ; on 
 "the good," 439. 
 
 Pons Varolii, 35. 
 
 Porter, Dr. Noah, on our experience 
 during sleep, 346. 
 
 Psychologists, their methods unreason- 
 ably charged, 3. 
 
 Public speaking, as it illustrates use 
 of speech, 301 ; as it illustrates nerve 
 action, 329. 
 
 Purkinje's experiment as to influence of 
 light on retina, 63. 
 
 Putnam on incision into grey matter, 
 105. 
 
 Qitain on proportion of brain to body, 22. 
 
 Quain's Anatomy, illustrations from : — 
 right side of brain, 14 ; upper surface, 
 17 ; corpus callosum, 30 ; section of 
 brain below this, 31 ; lower divisions 
 of nerve centre, 35. 
 
 Rabbit, brain of, 130. 
 
 Ranke on nerve fibre, 28. 
 
 Hat, brain of, 129. 
 
 Kate of transmission of nerve influence, 
 58. 
 
 Ratio of increasing sensibility, 57. 
 
 Recollection not a test of mental activity 
 during sleep, 336. 
 
 Reflex action, 237. 
 
 Reid, Dr., experience iu dreaming, 339 ; 
 escape from fear during sleep, 341. 
 
 Relations of philosophy and science, 1-3. 
 
 Results of anatomical and physiological 
 investigations as to brain, 187. 
 
 Retentiveness as it belongs to the mus- 
 cular system, 263 ; to the mind, 268. 
 
 Retina, structure of, 62 ; illumination 
 of, 63; colouring matter in, 65;. pos- 
 sibility of seeing the retina, 65. 
 
 Robertson, Dr. William, on affection of 
 the dog, 140. 
 
 Rolleston, Professor, on weight of brain 
 of orang, 14 ; on brain of orang, 
 159. 
 
 Rotatory motion, sense of, 73 ; giddiness, 
 322. 
 
 Sanderson, G. P., on the muscular 
 power, brain, habits, and intelligence 
 of the elephant, 176-181. 
 
 Sankey, Dr., on treatment of the insane, 
 388. 
 
 Saunders, Professor, on loss of speech, 305 . 
 
 Savage, Dr., on intelligence of the ape, 
 167. 
 
 Science, how related to philosophy, 1-3. 
 
 Scientific knowledge defined, 2. 
 
 Scientific methods applicable in mental 
 philosophy, 3. 
 
 Scoresby, Dr., on the brain and habits 
 of the whale, 182-186. 
 
 Searchers after truth must themselves 
 be included in the problem of exist- 
 ence, 1. 
 
 Section of a nerve fibre, 52. 
 
 Seguin's report on idiocy, 367 ; educa- 
 tion of idiots, 373. 
 
 Sensation, 1 94 ; as a form of knowledge, 
 213 ; analysis of experience, 214 ; suc- 
 cessive sensations, and the discrimina- 
 tion of them, 215 ; voluntary use of 
 sensory apparatus, 217 ; personality 
 as related to sensation, 222. 
 
 Sensibility, ratio of increase, 52. 
 
 Sensibility at peripheral extremity of 
 sensory nerve, 191. 
 
 Sensory nerves, 41 ; apparatus, 189 ; 
 action of, along with intellect, 329; 
 rest for, in sleep, 333. 
 
 Severini, Dr., report on case of Gran- 
 doni, 372. 
 
 Shakespeare, vocabulary of, 277. 
 
 Sidey, Dr. James, case of loss of brain 
 substance, 401. 
 
 Sight-purple, 65. 
 
 " Silent regions " of the brain, under 
 electric excitation, 117, 254. 
 
 Simpson, Sir James, weight of his brain, 
 23. 
 
 Single nerve fibres more difficult to 
 govern than groups, 57. 
 
 Size of the brain, 12. 
 
 Skill, as illustrating physical aptitude 
 and intellectual direction, 242, 256. 
 
 Sleep, as rest to the sensory and motor 
 systems, 333 ; compatible with mental 
 activity, 334 ; recollection not » test 
 of this, 336 ; exercise of imagination 
 during, 338 ; persistent determination 
 during, 340 ; concentrated intellec- 
 tual action during, 342 ; " mesmeric 
 sleep," 359 ; sleep during work, 353. 
 
INDEX. 
 
 455 
 
 Socrates on ethical conceptions, 439 ; 
 on a future state, 448. 
 
 "Somatist," reason for preferring the 
 name to "materialist," 424. 
 
 Somnambulism, contrast with dreaming, 
 352 ; examples of, 353. 
 
 Special sense, nerves of, 39. 
 
 Special senses, as related to intelligence, 
 227. 
 
 Speculative thought, 438. 
 
 Speech, use of, 285 ; mechanism of; 287 ; 
 intelligence as requisite for, 287 ; imi- 
 tative tendency, 289 ; comparison of 
 this in child and animal, 292 ; public 
 discourse, 303 ; loss of speech, 304. 
 
 Spencer, Herbert, on influence of environ- 
 ment, 220 ; universality of religious 
 ideas, 437. 
 
 Spinal marrow, 39. 
 
 Spinal nerves, 40. 
 
 Spinoza on the true method of philoso- 
 phising, 439. 
 
 Stewart, Professor T. Grainger, case of 
 aphasia, 312. 
 
 Structure of the brain, 10. 
 
 Summary of intellectual results, 441. 
 
 Surface, upper, of brain, 17. 
 
 Sympathetic system of nerves, 46. 
 
 Tait, Professor, on Force, 200. 
 
 Terminal organs of the special senses 
 compared with terminal part of the 
 ordinary sensory nerve, 77. 
 
 Thought, relation of, to language, 330 ; 
 demand of, upon brain energy, 331. 
 
 Thurnam on average stature of women, 
 21 ; on brain-weight, 23. 
 
 Tiedemann, proportion of brain to body, 
 21. 
 
 Touch-corpuscles, 42. 
 
 Trance, state of, 356 ; " mesmeric," 359. 
 
 Trousseau's case of injury to frontal 
 lobes, 395. 
 
 Turner, Professor, on weight of brain, 13 ; 
 on difference of brain weight in man 
 and woman, 21 ; average weight of 
 European brain, 21 ; on difference be- 
 tween nerve line and its enclosure, 28 ; 
 author's obligations to, 123 ; on brain 
 of whale, 186. 
 
 Turner's Anatomy, illustrations from : — 
 outer covering of brain, 1 1 ; brain as in 
 the skull, 12; outline of convolutions, 
 
 18 j section of grey matter, 26 ; nerve 
 fibre, 28 ; basal ganglia, 32 ; lower 
 surface, 34 ; section of spinal cord, 
 40 ; tOuch-cOrpuscles, 43 ; structure 
 of the eyeball, 61 ; structure of the 
 retina, after Schultze, 63 ; section of 
 the ear, 70 ; labyrinth, 73. 
 
 Tylor, Dr. E. B., on religious conceptions 
 among uncivilised tribes, 436-437. 
 
 Tyndall on the passage from brain action 
 to consciousness, 212. 
 
 Uhcouscioitsness, state of, 348'; as re- 
 sulting from physical injury, 349 ; 
 from mental agitation, 350. 
 
 Virchow on neuroglia, 25. 
 
 Vision, binocular, 67. 
 
 Vogt, Carl, on microcephaly, 367. 
 
 Voluntary and Involuntary Muscles, 45. 
 
 Voluntary action connected with sensa- 
 tion, 217 ; with motor activity, 239, 
 255. 
 
 "Voluntary muscles," 259. 
 
 Wagner's (Pud.), illustrations of convo- 
 lutions, 20 ; statistics on brain weight, 
 24. 
 
 Wallace, Alfred Pussell, on the Orang, 
 158 ; intelligence of, 167 ; a baby 
 orang, 169. 
 
 Weariness, as related to intellectual 
 effort, 326. 
 
 Webster, Daniel, weight of his brain, 23. 
 
 Weight of the brain, 13 ; relation of this 
 to weight of body, 13; difference of, 
 in the case of men and women, 21 ; 
 examples of great, 23. 
 West Elding (Yorkshire) Asylum Reports, 
 high brain weight with insanity, 22 ; 
 method of determining depth of grey 
 matter, 25 ; difference of cells in 
 layers of the grey matter, 27 ; electric 
 excitation of brain, 82. 
 
 Whale, brain of, 181 ; affection of, 185. 
 
 White matter of the brain, 28. 
 
 Will-power as connected with muscular 
 activity, 247 ; can it be referred to 
 nerve force? 253. 
 
 Ziemssen's Cyclopcedia of the Practice of 
 Medicine,, — Diseases of the Nervous 
 System, 287, 288, 292, 296. 
 
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PHYSICAL SCIENCE. 
 
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SCIENTIFIC CATALOGUE. 
 
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PHYSICAL SCIENCE. 
 
 Huxley (Professor) — continued. 
 
 the Natural History Sciences: — (6) On the Study of Zoology: — 
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PHYSICAL SCIENCE. 13 
 
 Macmillan (Rev. Hugh) — continued. 
 FIRST FORMS OF VEGETATION. Second Edition, corrected 
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 tions. Globe 8vo. 6s. 
 
 The first edition of this book mas published under the name of 
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 Mansfield (C. B.) — Works by the late C. B. Mansfield :— 
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1 4 SCIENTIFIC CATALOGUE. 
 
 Mivart (St. George)— continued. 
 
 THE COMMON FROG. With Numerous Illustrations. Crown 
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 LESSONS IN ELEMENTARY BOTANY. With nearly Two 
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 Types. The concluding chapters are entitled, " How to Dry 
 
PHYSICAL SCIENCE. 15 
 
 Oliver — continued. 
 
 Plants" and "How to Describe Plants?' A valuable Glossary is 
 appended to the volume. In the preparation of this work free use 
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 Henslow. 
 
 FIRST BOOK OF INDIAN BOTANY. With numerous 
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 Penrose (F. C.)— ON A METHOD OF PREDICTING BY 
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 Prestwich.— THE PAST AND FUTURE OF GEOLOGY. 
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 Radcliffe.— PROTEUS : OR UNITY IN NATURE. By. C. 
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16 SCIENTIFIC CATALOGUE. 
 
 Rendu.— THE THEORY OF THE GLACIERS OF SAVOY. 
 By M. le Chanoine Rendu. Translated by A. Wells, Q.C., 
 Jate President of the Alpine Club. To which are added, the Original 
 Memoir and Supplementary Articles by Professors Tait and Rus- 
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 ROSCOC — Works by Henry E. Roscoe, F.R.S., Professor of 
 Chemistry in Owens College, Manchester : — 
 
 LESSONS IN ELEMENTARY CHEMISTRY, INORGANIC 
 AND ORGANIC, With numerous Illustrations and Chiomo- 
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 CHEMICAL PROBLEMS, adapted to the above by Professor 
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 " We unhesitatingly pronounce it the best of all our elementary 
 treatises on Chemistry." — Medical Times. 
 
 PRIMER OF CHEMISTRY. Illustrated. i8mo. is. 
 
 Roscoe and Schorlemmer. — a treatise ON CHE- 
 MISTRY. By Professors Roscoe and Schorlemmer. 
 Vol. I., The Non-metallic Elements. With numerous Illustrations 
 
 and Portrait of Dalton. Medium 8vo. 211. 
 Vol. II., Metals, Part I. With Illustrations. 8vo. 18s. 
 
 " Regarded as a treatise on the Non-metallic Elements, there can be 
 no doubt that this volume is incomparably the most satisfactory one 
 of which we are in possession." — Spectator. 
 ' ' It would be difficult to praise the work too highly. All the merits 
 which we noticed in the first volume are conspicuous in the second. 
 The arrangement is clear and scientific ; the facts gained by modern 
 research are fairly represented and judiciously selected; and the 
 style throughout is singularly lucid. " — Lancet, 
 
 [Metals, Part II. in the Press. 
 
 Rumford (Count).— THE LIFE AND COMPLETE WORKS 
 OF BENJAMIN THOMPSON, COUNT RUMFORD. With 
 Notices of his Daughter. By George Ellis. With Portrait. 
 Five Vols. 8vo. 4/. 14J. 6d. 
 
 Schorlemmer.— A MANUAL OF THE CHEMISTRY OF 
 THECARBON COMPOUNDS OR ORGANIC CHEMISTRY. 
 By C. Schorlemmer, F.R.S., Lecturer in Organic Chemistry in 
 Owens College, Manchester. 8vo. 14?. 
 " It appears to us to be as complete a manual of the metamorphoses of 
 
 carbon as could be at present produced, and it must prove eminently 
 
 useful to the chemical student. '' — Atheiueum. 
 
PHYSICAL SCIENCE. 17 
 
 Shann. — an elementary treatise on heat, in 
 
 RELATION TO STEAM AND THE STEAM ENGINE. 
 By G. Shann, M.A. With Illustrations. Crown 8vo. 4s. 6d. 
 
 Smith.— HI STORIA FILICUM : An Exposition of the Nature, 
 Number, and Organography of Ferns, and Review of the Prin- 
 ciples upon which Genera are founded, and the Systems of Classifi- 
 cation of the principal Authors, with a new General Arrangement, 
 &c. By J. Smith. A.L.S., ex-Curator of the Royal Botanic 
 Garden, Kew. With Thirty Lithographic Plates by W. H. Fitch, 
 F.L.S. Crown 8vo. 12s. 6d. 
 
 " No one anxious to work up a thorough knowledge of ferns can 
 afford to do without it," — Gardener's Chronicle. 
 
 South Kensington Science Lectures. — Vol. I.— Con- 
 taining Lectures by Captain Abney, F.RS., Professor' Stokes, 
 Professor .Kennedy, F. J. Bramwell, F.R.S., Professor G. 
 Forbes, H. C. Sorby, F.R.S., J. T. Bottomley, F.R.S.E., 
 S. H. Vines, B.Sc, and Professor Carey Foster. Crown 8vo. 
 6s. [Vol. II. nearly ready. 
 
 Spottiswoode.— POLARIZATION OF LIGHT. By W. 
 Spottiswoode, President of the Royal Society'. With numerous 
 Illustrations. Second Edition. Cr. 8vo. 3s. 6d. (Nature Series.) 
 " The illustrations are exceedingly well adapted to assist in making 
 
 the text comprehensible" — Athenaeum. "A clear, trustworthy 
 
 manual. " — Standard. 
 
 Stewart (B.) — Works by Balfour Stewart, F.R.S., Professor 
 of Natural Philosophy in Owens College, Manchester : — 
 LESSONS IN ELEMENTARY PHYSICS. With numerous 
 Illustrations and Chromolithos of the Spectra of the Sun, Stars, 
 and Nebulae. New Edition. Fcap. 8vo. 4s. 6d. 
 The Educational Times calls this the beau-idial of a scientific text- 
 book, clear, accurate, and thorough." 
 PRIMER OF PHYSICS. With Illustrations. New Edition, with 
 Questions. l8mo. is. 
 Stewart and Tait.— THE UNSEEN UNIVERSE: or, 
 Physical Speculations on a Future State. By Balfour Stewart, 
 F.R.S., and P. G. Tait, M.A. Sixth Edition. Crown 8vo. 6s. 
 " The book is one which well deserves the attention of thoughtful ana 
 religious readers. . . . It is a perfectly sober inquiry, on scientific 
 grounds, into the possibilities of a future existence." — Guardian. 
 
 Tait.— LECTURES ON SOME RECENT ADVANCES IN 
 PHYSICAL SCIENCE. By P. G. Tait, M.A., Professor of 
 Philosophy in the University of Edinburgh. Second edition, 
 revised and enlarged, with the Lecture on Force delivered before 
 the British Association. Crown 8vo. 9s. 
 
 B 
 
SCIENTIFIC CATALOGUE. 
 
 Tanner.— FIRST PRINCIPLES OF AGRICULTURE. By 
 Henry Tanner, F.C.S., Professor of Agricultural Science, 
 University College, Aberystwith, Examiner in the Principles of 
 Agriculture under the Government Department of Science. l8mo. 
 is. 
 
 Taylor. — SOUND AND MUSIC : A Non-Mathematical Trea- 
 tise on the Physical Constitution of Musical Sounds and Harmony 
 including the Chief Acoustical Discoveries of Professor Helm 
 holtz. By Sedley Taylor, MA., late Fellow of Trinity Col 
 ledge, Cambridge. Large crown 8vo. Ss. 6d. 
 " In no previous scientific treatise do we remember so exhaustive and 
 
 so richly illustrated a description of forms of vibration and of 
 
 wave-motion in fluids" — Musical Standard. 
 
 Thomson. — Works by Sir Wyviixe Thomson, K.C.B., F.R.S. 
 THE DEPTHS OF THE SEA : An Account of the General 
 Results of the Dredging Cruises of H.M. SS. "Porcupine" and. 
 "Lightning" during the Summers of 1868-69 and 70, under the 
 scientific direction of Dr. Carpenter, F.R.S., J. Gwyn Jeffreys, 
 F.R.S., and Sir Wyville Thomson, F.R.S. With nearly 100 
 Illustrations and 8 coloured Maps and Plans. Second Edition. 
 Royal 8vo. cloth, gilt. 3U. 6d. 
 
 The Athenseum says : ' ' The book is full of interesting matter, and 
 1 is written by a master of the art of popular exposition. It is 
 excellently illustrated, both coloured maps and woodcuts possessing 
 high merit. Those who have already become interested in dredging 
 operations will of course make a point of reading this work ; those 
 who wish to be pleasantly introduced to the subject, and rightly 
 to appreciate the news which arrives from time to time from the 
 ' Challenger,' should not fail to seek instruction from it." 
 
 THE VOYAGE OF THE "CHALLENGER."— THE ATLAN- 
 TIC. A Preliminary account of the Exploring Voyages of H.M.S. 
 "Challenger," during the year 1873 and the early part of 1876. 
 With numerous Illustrations, Coloured Maps & Charts, & Portrait 
 of the Author, engraved.byC. H. Jeens. 2 Vols. Medium 8vo. 42J. 
 The Times says : — " It is right that the public should have some 
 authoritative account of the general results of the expedition, and 
 that as many of the ascertained data as may be accepted with con- 
 fidence should speedily find their place in the general body of 
 scientific knowledge. No one can be more competent than the 
 accomplished scientific chief of the expedition to satisfy the public in 
 this respect. . . . The paper, printing, and especially the numerous 
 illustrations', are of the highest quality. . . . We have rarely, if 
 ever, seen more beautiful specimens of wood engraving than abound 
 in this work. . . . Sir Wyville Thomson's style is particularly 
 attractive; he is easy and graceful, but vigorous and exceedingly 
 
PHYSICAL SCIENCE. 19 
 
 Thomson — continued. 
 
 happy in the choice of language, and throughout the work there are 
 touches which show that science has not banished sentiment from 
 his bosom." 
 
 Thudichum and Dupre — A TREATISE ON THE 
 ORIGIN, NATURE, AND VARIETIES OF WINE. 
 Being a Complete Manual of Viticulture and (Enology. By J. L. 
 W. Thudichum, M.D., and August Dupre, Ph.D., Lecturer on 
 Chemistry at Westminster Hospital. Medium 8vo. cloth gilt. 25*. 
 
 "A treatise almost unique for its usefulness either to the wine-grower, 
 the vendor, or the consumer of wine. The analyses of wine are 
 the most complete we have yet seen, exhibiting at a glance the 
 constituent principles 0/ nearly all the wines known in this country. " 
 — Wine Trade Review. 
 
 Wallace (A. R.) — Works by Alfred Russel Wallace. 
 CONTRIBUTIONS TO THE THEORY OF NATURAL 
 SELECTION. A Series of Essays. New , Edition, with 
 Corrections and Additions. Crown 8vo. Ss. 6d. 
 
 Dr. Hooker, in his address to the British Association, spoke thus 
 of the author: "Of Mr. Wallace and his many contributions 
 to philosophical biology it is not easy to speak without enthu- 
 siasm; for, putting aside their great merits, he, throughout his " 
 writings, with a modesty as rare as I believe it to be uncon- 
 scious, forgets his own unquestioned claim to the honour of 
 having originated independently of Mr.' Darwin, the theories 
 which he so ably defends." The Saturday Review says: "He 
 has combined an abundance of fresh and original facts with a 
 liveliness and sagacity of reasoning which are not often displayed 
 so effectively on so small a scale." 
 
 THE GEOGRAPHICAL DISTRIBUTION OF ANIMALS, 
 with a study of the Relations of Living and Extinct Faunas as 
 Elucidating the Past Changes of the Earth's Surface. 2 vols. 8vo. 
 with Maps, and numerous Illustrations by Zwecker, ifls. 
 
 The Times says: "Altogether it is a wonderful and fascinating 
 story, whatever objections may be taken to theories founded upon 
 it. Mr. IVallace has not attempted to add to its interest by any 
 adornments of style; he has given a simple and clear statement of 
 intrinsically interesting facts, and what he considers to be legiti- 
 mate inductions from them. Naturalists ought to be grateful to 
 him for having undertaken so toilsome a task. The work, indeed, 
 is a credit to all concerned — the author, the publishers, the artist — 
 unfortunately now no more — of the attractive illustrations — last 
 but by no means least, Mr. Stanford's map-designer" 
 
20 SCIENTIFIC CATALOGUE. 
 
 Wallace (A. R.)— continued. 
 TROPICAL NATURE : with other Essays. 8vo. \is. 
 
 ' ' Nowhere amid the -many descriptions of the tropics that have been 
 given is to be found a sumviary of the past history and actual 
 phenomena of the tropics which gives that which is distinctive of 
 the phases of nature in them more clearly, shortly, and impres- 
 sively." — Saturday Review. 
 
 Waritlgton. — THE WEEK OF CREATION; OR, THE 
 COSMOGONY OF GENESIS CONSIDERED IN ITS 
 RELATION TO MODERN SCIENCE. By George War- 
 ington, Author of " The Historic Character of the Pentateuch 
 Vindicated." Crown 8vo. 4s. 6d. 
 
 Wilson. — RELIGIO CHEMICI. By the late George Wilson, 
 M.D. , F.R.S.E., Regius Professor of Technology in the University 
 of Edinburgh. With a Vignette beautifully engraved after a 
 design by Sir Noel Paton. Crown 8vo. 8s. 6d. 
 "A more fascinating volume," the Spectator says, "has seldom 
 fallen into our hands. " 
 
 Wilson (Daniel.)— CALIBAN : a Critique on Shakespeare's 
 "Tempest" and "Midsummer Night's Dream." By Daniel 
 Wilson, LL. D., Professor of History and English Literature in 
 University College, Toronto. 8vo, tos. 6d. 
 
 ' ' The whole volume is most rich in the eloquence of thought and 
 imagination as well as of words. It is a choice contribution at 
 once to science, theology, religion, and literature." — British 
 Quarterly Review. 
 
 Wright.— METALS AND THEIR CHIEF INDUSTRIAL 
 APPLICATIONS. By C. Alder Wright, D.Sc, &c, Lec- 
 turer on Chemistry in St. Mary's Hospital School. Extra fcap. 
 8vo. 3 j. 6d. 
 
 Wurtz.— A HISTORY OF CHEMICAL THEORY, from the 
 
 Age of Lavoisier down to the present time. By Ad. Wurtz. 
 
 Translated by Henry Watts, F.R.S. Crown 8vo. 6s. 
 
 " The discourse, as a resume' of chemical theory and research, unites 
 
 singular luminousness and grasp. A few judicious notes are added 
 
 by the translator." — Pall Mall Gazette. " The treatment of the 
 
 subject is admirable, and the translator has evidently done his duty 
 
 most efficiently." — Westminster Review. 
 
MENTAL AND MORAL PHILOSOPHY, ETC. 21 
 
 WORKS ON MENTAL AND MORAL 
 IILOSOPHY, AND ALLIED SUBJECTS. 
 
 StOtle. — AN INTRODUCTION TO ARISTOTLE'S 
 RHETORIC. With Analysis, Notes, and Appendices. By E. 
 M. Cope, Trinity College, Cambridge. 8vo. 14.J. 
 ilSTOTLE ON FALLACIES; OR, THE SOPHISTICI 
 ELENCHI. With a Translation and Notes by Edward Poste, 
 M.A., Fellow of Oriel College, Oxford. 8vo. %s. 6d. 
 
 ks. — Works by the Rev. T. R. Birks, Professor of Moral Philo- 
 sophy, Cambridge : — 
 
 FIRST PRINCIPLES OF MORAL SCIENCE ; or, a Firs 
 Course of Lectures delivered in the University of Cambridge. 
 Crown 8vo. &s. 6d. 
 
 This work treats of three topics all preliminary to the direct exposi- 
 tion of Moral Philosophy. These are the Certainty and Dignity 
 • of Moral Science, its Spiritual Geography, or relation to other 
 main subjects of human thought, and its Formative Principles, or 
 some elementary truths on which its whole development must 
 depend. 
 ODERN UTILITARIANISM; or, The Systems of Paley, 
 Bentham, and Mill, Examined and Compared. Crown 8vo. 6s. 6d. 
 ODERN PHYSICAL FATALISM, AND THE DOCTRINE 
 OF EVOLUTION ; including an Examination of Herbert Spen- 
 cer's First Principles. C r °wn 8vo. 6s. 
 
 )le. — AN INVESTIGATION OF THE LAWS OF 
 THOUGHT, ON WHICH ARE FOUNDED THE 
 MATHEMATICAL THEORIES OF LOGIC AND PRO- 
 BABILITIES. By George Boole, LL.D., Professor of 
 Mathematics in the Queen's University, Ireland, &c. 8vp. 14^. 
 
 :ler.— LECTURES ON THE HISTORY OF ANCIENT 
 PHILOSOPHY. By W. Archer Butler, late Professor of 
 Moral Philosophy in the University of Dublin. Edited from the 
 Author's MSS., with Notes, by William Hepworth Thomp- 
 son, M.A., Master of Trinity College, and Regius Professor of 
 Sreek in the University of Cambridge. New and Cheaper Edition, 
 revised by the Editor. ' 8vo. 12.5. 
 
 rd— A CRITICAL ACCOUNT OF THE PHILOSOPHY 
 
 DF KANT. With an Historical Introduction. By E. Caird, 
 M.A., Professor of Moral Philosophy in the University of Glasgow. 
 Svo. i8j. 
 
SCIENTIFIC CATALOGUE. 
 
 Calderwood. — Works by the Rev. Henry Calderwood, M.A., 
 LL.D., Professor of Moral Philosophy in the University of Edin- 
 burgh : — 
 PHILOSOPHY OF THE INFINITE : A Treatise on Man's 
 Knowledge of the Infinite Being, in answer to Sir W. Hamilton 
 and Dr. Mansel. Cheaper Edition. 8vo. "]s. 6d. 
 "A book of great ability .... written in a clear style, and may 
 be easily understood by even those who are not versed in such 
 discussions." — British Quarterly Review. 
 A HANDBOOK OF MORAL PHILOSOPHY. New Edition. 
 Grown 8vo. 6s. 
 
 "Itis, wefeel convinced, the best handbook on the subject, intellectually 
 and morally, and does inAnite credit to its author.'' 1 — Standard. 
 "A compact and useful work, going over a great deal of ground 
 in a manner adapted to suggest and facilitate further study. . . . 
 His book will be an assistance to many students outside his own 
 University of Edinburgh. — Guardian. 
 THE RELATIONS OF MIND AND BRAIN. [Nearly ready. 
 
 Fiske.— OUTLINES OF COSMIC PHILOSOPHY, BASED 
 ON THE DOCTRINE OF EVOLUTION, WITH CRITI- 
 CISMS ON THE POSITIVE PHILOSOPHY. By John 
 Fiske, M.A., LL.B., formerly Lecturer on" Philosophy at 
 Harvard University. 2 vols. 8vo. 25J. 
 
 " The work constitutes a very effective encyclopaedia of the evolution- 
 ary philosophy, and is well worth the study of all who wish to see 
 at once the entire scope and purport of the scientific dogmatism of 
 the day." — Saturday Review. 
 
 Herbert.— THE REALISTIC ASSUMPTIONS OF MODERN 
 SCIENCE EXAMINED. By T. M. Herbert, M.A., late 
 Professor of Philosophy, &c, in the Lancashire Independent 
 College, Manchester. 8vo. 14J. 
 
 Jardine.— THE ELEMENTS OF THE PSYCHOLOGY OF 
 COGNITION. By Robert Jardine, B.D., D.Sc, Principal oi 
 the General Assembly's College, Calcutta, and Fellow of the Uni- 
 versity of Calcutta. Crown 8vo. 6s. 6d. 
 
 Jevons. — Works by W. Stanley Jevons, LL.D., M.A., F.R.S., 
 Professor of Political Economy, University College, London. 
 THE PRINCIPLES OF SCIENCE. A Treatise on Logic and 
 Scientific Method. New and Cheaper Edition, revised. Crown 
 8vo. 12s. 6d. 
 
 " No one in future can be said to have any true knowledge of what 
 has been done in the way of logical and scientific method in 
 England without having carefully studied Professor Jevons' 
 book." — Spectator. 
 
MENTAL AND MORAL PHILOSOPHY, ETC. 23 
 
 evon S — continued. 
 THE SUBSTITUTION OF SIMILARS, the True Principle of 
 
 Reasoning. Derived from a Modification of Aristotle's Dictum. 
 
 Fcap. 8vo. is. 6d. 
 ELEMENTARY LESSONS IN LOGIC, DEDUCTIVE AND 
 
 INDUCTIVE. With Questions, Examples, and Vocabulary of 
 
 Logical Terms. New Edition. Fcap. 8vo. 3-r. 6d. 
 PRIMER OF LOGIC. New Edition. i8mo. is. 
 
 WaCCOll. — THE GREEK SCEPTICS, from Pyrrho to Sextus. 
 An Essay which obtained the Hare Prize in the year 1868. By 
 Norman Maccoll, B.A., Scholar of Downing College, Cam- 
 bridge. Crown 8vo. y. (id. 
 
 M'Cosh. — Works by J AMES M'Cosh,LL.D., President of Princeton 
 
 College, New Jersey, U.S. 
 
 ' ' He certainly shows himself skilful in that application of logic to 
 psychology, in that inductive science of the human mind which is 
 the fine side of English philosophy. His philosophy as a whole is 
 worthy of attention." — Revue de Deux Mondes. 
 
 THE METHOD OF THE DIVINE GOVERNMENT, Physical 
 
 and Moral. Tenth Edition. 8vo. 10s. 6d. 
 
 ' ' This work is distinguished from other similar ones by its being 
 based upon a thorough study of physical science, and an accurate 
 knowledge of its present condition, and by its entering in a 
 deeper and more unfettered manner than its predecessors upon the dis- 
 cussion of the appropriate psychological, ethical, and theological ques- 
 tions. The author keeps aloof at once from the a priori idealism and 
 dreaminess of German speculation since Schelling, and from the 
 onesidedness and narrowness of the empiricism and positivism 
 which have so prevailedin England." — Dr. Ulrici, in "Zeitschrift 
 fur Philosophie." 
 THE INTUITIONS OF THE MIND. A New Edition. 8vo. 
 
 cloth, 10s. 6d. 
 
 "The undertaking to adjust the claims of the sensational and in- 
 tuitional philosophies, and of the a posteriori and a priori methods, 
 is accomplished in this work with a great amount of success." — 
 Westminster Review. "J value it for its large acquaintance 
 with English Philosophy, which has not led him to neglect the 
 sreat German works. I admire the moderation and clearness, as 
 well as comprehensiveness, of the author's views." — Dr. Dorner, of 
 Berlin. 
 AN EXAMINATION OF MR. J. S. MILL'S PHILOSOPHY: 
 
 Being a Delence ot Fundamental Truth. Second edition, with 
 
 additions. 10 s. 6d. 
 
 ' ' Such a work greatly needed to be done, and the author was the man 
 to do it. This volume is important, not merely in reference to the 
 
24 SCIENTIFIC CATALOGUE. 
 
 M ' C O sh — continued. 
 
 views of Mr. Mill, but of the whole school of writers, past and 
 present, British and Continental, he so ably represents." — Princeton 
 Review. 
 
 THE LAWS OF DISCURSIVE THOUGHT : Being a Text- 
 book of Formal Logic. Crown 8vo. p. 
 
 ' ' The amount of summarized information which it contains is very 
 great; and it is the only work on the very important subject with 
 which it deals. Never was such a work so much needed as in 
 the present day." — London Quarterly Review. 
 
 CHRISTIANITY AND POSITIVISM : A Series of Lectures to 
 the Times on Natural Theology and Apologetics. Crown 8vo. 
 7s. 6d. 
 
 THE SCOTTISH PHILOSOPHY FROM HUTCHESON TO 
 HAMILTON, Biographical, Critical, Expository. Royal 8vo. 16s. 
 
 Masson.— RECENT BRITISH PHILOSOPHY : A Review 
 with Criticisms ; including some Comments on Mr. Mill's Answer 
 to Sir William Hamilton. By David MASSON, M.A., Professor 
 of Rhetoric and English Literature in the University of Edinburgh. 
 Third Edition, with an Additional Chapter. Crown 8vo. 6s. 
 " We can nowhere point to a work which gives so clear an exposi- 
 tion of the course of philosophical speculation in Britain during 
 the past century, or which indicates so instructively the mutual in- 
 fluences of philosophic and scientific thought. " — Fortnightly Review. 
 
 Maudsley. — Works by H. Maudsley, M.D., Professor of Medical 
 Jurisprudence in University College, London. 
 
 THE PHYSIOLOGY OF MIND ; being the First Part of a Third 
 Edition, Revised, Enlarged, and in great part Rewritten, of "The 
 Physiology and Pathology of Mind. Crown 8vo. los. 6d. 
 
 THE PATHOLOGY OF MIND. [In the Press. 
 
 BODY AND MIND : an Inquiry into their Connexion and Mutual 
 Influence, specially with reference to Mental Disorders. An 
 Enlarged and Revised edition. To which are added, Psychological 
 Essays. Crown 8vo. 6s. 6d. 
 
 Maurice. — Works by the Rev. Frederick Denison Maurice, 
 ■ M.A., Professor of Moral Philosophy in the University of Cam- 
 bridge. (For other Works by the same Author, see Theological 
 Catalogue.) 
 
 SOCIAL MORALITY. Twenty-one Lectures delivered in the 
 University of Cambridge. New and Cheaper Edition. Crown 8vo. 
 ioj-. 6d. 
 
MENTAL AND MORAL PHILOSOPHY, ETC. 25 
 
 MI aur 1 ce — continued, 
 
 " Whilst reading it we are charmed, by the freedom from, exclusiveness 
 and prejudice, the large charity, the loftiness of thought, the eager- 
 ness to recognize and appreciate whatever there is of real worth 
 extant in the world, which animates it from one end to the other. 
 We gain new thoughts and new ways of viewing things, even more, 
 perhaps, from, being brought for a time under the influence of so 
 noble and spiritual a mind." — Athenaum. 
 
 THE .CONSCIENCE : Lectures on Casuistry, delivered in the Uni- 
 versity of Cambridge. New and Cheaper Edition. Crown 8vo. $s. 
 
 The Saturday Review says : "We rise from them with detestation 
 of all that is selfish and mean, and with a living impression that 
 there is such a thing as goodness after all." 
 
 MORAL AND METAPHYSICAL PHILOSOPHY. Vol. I. 
 Ancient Philosophy fram the First to the Thirteenth Centuries ; 
 Vol. II. the Fourteenth Century and the French Revolution, with 
 a glimpse into the Nineteenth Century. New Edition and 
 Preface. 2 Vols. 8vo. 25^. 
 
 Morgan.— ANCIENT SOCIETY : or Researches in the Lines of 
 Human Progress, from Savagery, through Barbarism to Civilisation. 
 By Lewis H. Morgan, Member of the National Academy of 
 ' Sciences. 8vo. ids. 
 
 Murphy, — the scientific bases of faith. By 
 
 Joseph John Murphy, Author of " Habit and Intelligence." 
 8vo. i\s. 
 
 " The book is not without substantial value ; the writer continues the 
 
 f work of the best apologists of the last century, it may be with less 
 
 force and clearness, but still with commendable persuasiveness and 
 
 tact; and with an intelligent feeling for the changed conditions of 
 
 the problem." — Academy. 
 
 Paradoxical Philosophy. — A Sequel to "The Unseen Uni- 
 verse." Crown 8vo. Is. (td. 
 
 Picton. — THE MYSTERY OF MATTER AND OTHER 
 ESSAYS. By J. Allanson Picton, Author of " New Theories 
 and the Old Faith." Cheaper issue with New Preface. Crown 
 8vo. 6s. 
 
 Contents i— The Mystery of Matter — The Philosophy of Igno- 
 rance The Antithesis of Faith and Sight — The Essential Nature 
 
 of Religion — Christian Pantheism. 
 
26 SCIENTIFIC CATALOGUE. 
 
 Sidgwick.— THE METHODS OF ETHICS. , By Henry 
 Sidgwick, M.A., Prelector in Moral and Political Philosophy in 
 Trinity College, Cambridge. Second Edition, revised throughout 
 with important additions. 8vo. l+r. 
 
 A SUPPLEMENT to the First Edition, containing all the important 
 additions and alterations in the Second. 8vo. 2S. 
 
 " This excellent and very welcome volume Leaving to meta- 
 physicians any further discussion thai may be needed respecting the 
 already over-discussed problem of the origin of the moral faculty, he 
 takes it for granted as readily as the geometrician takes space for 
 granted, or the physicist the existence of matter. But he takes little 
 else for granted, and defining ethics as ' the science of conduct, ' be 
 carefully examines, not the various ethical systems that have been 
 propounded by Aristotle and Aristotle's followers downwards, but 
 the principles upon which, so far as they confine themselves to the 
 strict province of ethics, they are based.'" — Athenjeum. 
 
 Thornton.— OLD-FASHIONED ETHICS, AND COMMON- 
 SENSE METAPHYSICS, with some of their Applications. By 
 William Thomas Thornton, Author of " A Treatise on Labour. 
 8vo. iar. td. 
 
 The present volume aeals with problems which are agitating the 
 minds of all thoughtful men. The following are the Contents : — 
 L Ante- Utilitarianism. II. History's Scientific Pretensions. III. 
 David Hume as a Metaphysician. IV. Huxleyism. V. Recent 
 Phase of Scientific Atheism. VI. Limits of Demonstrable Theism. 
 
 Thring.(E., M. A.)— THOUGHTS ON LIFE-SCIENCE. 
 By Edward Thring, M.A. (Benjamin Place), Head Master of 
 Uppingham School. New Edition, enlarged and revised. Crown 
 8vo. Js. 6d. 
 
 Venn.— THE LOGIC OF CHANCE : An Essay on the Founda- 
 tions and Province of the Theory of Probability, with especial 
 reterence to its logical bearings, and its application to Moral and 
 Social Science. By John Venn, M.A., Fellow and Lecturer of 
 Gonville and Caius College, Cambridge. Second Edition, re- 
 written and greatly enlarged. Crown 8vo. lOr. 6d. 
 " One of the most thoughtful and philosophical treatises on any sub- 
 ject connected with logic and evidence which has been produced in 
 this or any other country for many years." — Mill's Logic, vol. ii. 
 p. 77. Seventh Edition. 
 
SCIENCE PRIMERS. 27 
 
 SCIENCE PRIMERS FOR ELEMENTARY 
 SCHOOLS. 
 
 Under the joint Editorship of Professors Huxley, Roscoe, and 
 Balfour Stewart. 
 
 Chemistry — By H. E. Roscoe, F.R.S., Professor of Chemistry 
 in Owens College, Manchester. With numerous Illustrations. 
 l8mo. is. New Edition. With Questions. 
 
 Physics — By Balfour Stewart, F.R.S., Professor of 
 Natural Philosophy in Owens College, Manchester. With numer- 
 ous Illustrations. i8mo. is. New Edition. With Questions. 
 
 Physical Geography. _By Archibald Geikie, F.R.S., 
 Murchison Professor of Geology and Mineralogy at Edinburgh. 
 With numerous Illustrations. New Edition with Questions. 
 i8mo. is. 
 
 Geology By Professor Geikie, F.R.S. With numerous Illus- 
 trations. New Edition. i8mo. cloth, is. 
 
 Physiology — By Michael Foster, M.D., F.R.S. With 
 numerous Illustrations. New Edition. l8mo. is. 
 
 Astronomy — By J. Norman Lockyer, F.R.S. With numerous 
 Illustrations. New Edition. i8mo. is. 
 
 Botany — By Sir J. D. Hooker, K.C.S.I., C.B., F.R.S. With 
 numerous Illustrations. New Edition. i8mo. is. 
 
 Logic — By Professor Stanley Jevons, F.R.S. New Edition. 
 i8mo. is. 
 
 Political Economy — By Professor Stanley Jevons, F.R.S. 
 iSmo. IS. 
 
 In preparation : — 
 INTRODUCTORY. By Professor Huxley. &c. &c. 
 
 ELEMENTARY SCIENCE CLASS-BOOKS. 
 
 Astronomy — By the Astronomer Royal. POPULAR AS- 
 TRONOMY. With Illustrations. By Sir G. B. Airy, K.C.B., 
 Astronomer Royal. New Edition. l8mo. /\s. 6d. 
 
 Astronomy — elementary lessons in astronomy. 
 
 With Coloured Diagram of the Spectra of the Sun, Stars, and 
 Nebulae, and numerous Illustrations. By J. Norman Lockyer, 
 F.R.S. New Edition. Fcap. 8vo. $s. 6d. 
 
28 SCIENTIFIC CATALOGUE. 
 
 Elementary Science Class-books — continued. 
 QUESTIONS ON LOCKYER'S ELEMENTARY LESSONS 
 IN ASTRONOMY. For the Use of Schools. By John 
 Forbes Robertson. 181110, cloth limp. it. 6d. 
 
 Physiology — LESSONS IN ELEMENTARY PHYSIOLOGY. 
 
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