Philosophy proceeds in part by the asking of large, imprecise, and overgeneral questions. In the attempt to answer them, the questions themselves come to be reformulated with greater clarity, and one large question often comes to be replaced by several smaller ones. The history of pre-Socratic philosophy is the best example of this process, and Being first appeared on the philosophical scene as part of it. To the question "What is Being?" the Parmenidean answer that there is Being and nothing else besides Being appears to have the merit of truth, even if it is tautological truth. What is, is; and what is not, is not. But what Parmenides' question in fact contains is a nontautological demand for the characteristics of what is, to which the answer that Being is one, unchanging, and eternal is appropriate. Since the objects we perceive are many, changing, and transient, they do...