From Aristotle’s Ousia to Ibn Sina’s Jawhar

Abstract

There is a shift in the meaning of substance from ousia in Aristotle to jawhar in Ibn Sina. This change of meaning is not just something linguistic. It is due to two different views concerning substance in two different worlds, i.e., the Greek and the Muslim worlds. The Greek Aristotelian world is a world of ousias that are actually existent. For Aristotle, to be is to be existent. But the Qur’anic doctrine of creatio ex nihilo led Farabi, and Ibn Sina following him, to interpret the Aristotle’s prime mover as God, the Creator and Necessary Being, in relation to which other beings were interpreted as contingent beings. Thus the famous thesis of the distinction of essence and existence appeared in a definite form in Farabi and was elaborated in detail in Ibn Sina. Based on this view, unprecedented philosophical ideas appeared among the Muslim Aristotelian philosophers. The dichotomy of essence and existence in each jawhar led Ibn Rushd to conclude (wrongly) that in Ibn Sina’s view existence is an accident added to essence in the way an ordinary accident like whiteness qualifies a substance. Ibn Rushd’s understanding of Ibn Sina’s thesis is a misunderstanding that influenced the medieval philosophers, such as Thomas Aquinas, and modern philosophers, such as Descartes and Kant, as well. This paper deals with the origin and the later development of this thesis and its developed articulation by Ibn Sina.