Abstract

We will first examine the manner in which Descartes and Leibniz each defines the notion of substance; then the meaning that each of these authors attributes to this notion; finally, we shall analyze the relations between substances in their respective systems. This comparison should serve to throw light on the ontological determinations of this notion as it appears in the respective systems of Descartes and Leibniz as well as to differenciate between the rationalism of each to them.