Abstract
The doctrine of eternal recurrence, the claim that everytning that occurs does so not only once but infinitely many times, figures in the writings of Nietzsche in several forms, and it can be understood in different ways. Here I shall show that one of these approaches allows us to see the doctrine as a philosophical theory about the nature of reality: that is, as an ontological doctrine. The interpretation is worth exploring because it allows us not only to see what Nietzsche's arguments really are, but also to bring to light problems and objections that go unnoticed in most accounts of the idea.