Spinoza and the problem of other substances

ABSTRACTMost of Spinoza’s arguments for God’s existence do not rely on any special feature of God, but instead on merely general features of substance. This raises the following worry: those arguments prove the existence of non-divine substances just as much as they prove God’s existence, and yet there is not enough room in Spinoza’s system for all these substances. I argue that Spinoza attempts to solve this problem by using a principle of plenitude to rule out the existence of other substances and that the principle cannot be derived from the PSR, as many claim.Abbreviation: PSR: Principle of Sufficient Reason.