Abstract

In this article, I examine Leibniz’s criticism of Spinoza’s notion of priority by nature based on the first proposition in Spinoza’s Ethics. Leibniz provides two counterexamples: first, the number 10’s being 6+3+1 is prior by nature to its being 6+4; second, a triangle’s property that two internal angles are equal to the exterior angle of the third is prior by nature to its property that the three internal angles equal two right angles. Leibniz argues that Spinoza’s notion cannot capture these priority relations. Although this text has received some scholarly attention, Leibniz’s objection in this text has not been fully explained yet. I argue that evaluating Leibniz’s objection relies on how to understand Spinoza’s notion of conception: first, whether conception is co-extensive with inherence and causation; second, whether conception is mental.