Abstract

The dispute over the exact nature and status of possible worlds in Leibniz’s philosophy has proven difficult to resolve. The standard view, that there is one unique actual world and that possible worlds exist solely as ideas within God’s understanding, sits in tension with important metaphysical and theological components of Leibniz’s system. For example, Leibniz takes possible individuals to have some “essence or reality” in themselves and to strive for existence, which allows him to ground counterfactual claims and to overcome necessitarianism. However, scholars have long seen these claims as being at odds with God’s creation of one unique actual world. Catherine Wilson (2000) challenges the standard view’s claim that possible worlds are substantially different from the actual world, arguing instead that Leibniz’s metaphysical commitments are consistent with there being more than one actual world and that Leibniz has no way to block the claim that God would generate more than one such world. In this paper, I expand on Wilson’s account and argue, contrary to the standard view, that the key theses at the heart of Leibniz’s philosophical system entail modal realism—for Leibniz, there can be no ontological difference between possible and actual worlds.