 Given Spinoza’s embrace of the PSR and his efforts to explain other dependence relations (such as causation and, perhaps, inherence), it would be surprising and disappointing if modality got a free explanatory pass. Of course, we probably should not expect Spinoza to have anything like a full-blown theory of modality in the forms that contemporary metaphysicians now provide (for an example, see the entry on the  possibilism-actualism debate). Only in recent decades have philosophers come to appreciate how complex and rich the metaphysics of modality is, and Spinoza would be in good company if he says things that seem, by today’s standards, mostly underdeveloped. Nonetheless, he may have the beginnings of an account that helps illuminate his other modal commitments.