Abstract

Historians of philosophy claim that Aristotle was the first to discuss substance extensively. He analyzed this issue in his books, Categories, Metaphysics, and Physics, for three different purposes. In Categories, after examining the different types of subject and predicate, the first and second substances have been distinguished from each other. In Metaphysics, he has dealt with substance with the purpose of a search for the existentiality of existents based on four aspects: essence, universal, genus, and subject. Finally, in his Physics, another interpretation of substance has been given in order to clarify the issue of a fixed subject in the course of motion. Consequently, some of his critiques have accused him of self-contradiction in these works. This paper is intended to clarify this problem by reference to the works of Aristotle and the analyses of his commentators.