id	author	title	date	pages	extension	mime	words	sentences	flesch	summary	cache	txt
en-wikipedia-org-1271		Abstract and concrete - Wikipedia			.html	text/html	1933	319	53	In metaphysics, abstract and concrete are classifications that denote whether the object that a term describes has physical referents. Abstract objects have often garnered the interest of philosophers because they raise problems for popular theories. In ontology, abstract objects are considered problematic for physicalism and some forms of naturalism. Some, such as Ernst Mally,[5] Edward Zalta[6] and arguably, Plato in his Theory of Forms,[6] have held that abstract objects constitute the defining subject matter of metaphysics or philosophical inquiry more broadly. In modern philosophy, the distinction between abstract and concrete was explored by Immanuel Kant[7] and G. Gottlob Frege said that abstract objects, such as numbers, were members of a third realm,[9][10] different from the external world or from internal consciousness.[11] Abstract objects and causality[edit] Recently, there has been some philosophical interest in the development of a third category of objects known as the quasi-abstract. Concrete and abstract thought in psychology[edit] Abstract object theory Categories: Abstract object theory	./cache/en-wikipedia-org-1271.html	./txt/en-wikipedia-org-1271.txt