Peter van Inwagen is John Cardinal O'Hara Professor of Philosophy at the University of Notre Dame. He previously taught at Syracuse University for many years and earned his PhD from the University of Rochester under the direction of Richard Taylor. He is one of the leading figures in contemporary metaphysics, philosophy of religion, and philosophy of action. It is largely due to his work (An Essay on Free Will: Oxford University Press, 1983) that incompatiblism (libertarianism) about free will is once again respectable in mainstream analytical philosophy.

He has been known to suggest that the only objects that exist are living beings (like humans) and fundamental, indivisible particles. That is, literally speaking, nothing except for people has any parts - when we talk about the table being composed of four legs and a surface, we are instead speaking obliquely about electrons and the like.