This book is a defense of modal realism; the thesis that our world is but one of a plurality of worlds, and that the individuals that inhabit our world are only a few out of all the inhabitants of all the worlds. Lewis argues that the philosophical utility of modal realism is a good reason for believing that it is true.

The truthmaker objection to presentism (the view that only what exists now exists simpliciter) is that it lacks sufficient metaphysical resources to ground truths about the past. In this paper I identify five constraints that an adequate presentist response must satisfy. In light of these constraints, I examine and reject responses by Bigelow, Keller, Crisp, and Bourne. Consideration of how these responses fail, however, points toward a proposal that works; one that posits God’s memories as truthmakers for truths about the (...) past. I conclude that presentists have, in the truthmaker objection, considerable incentive to endorse theism. (shrink)