Going about our daily lives in an orderly manner requires us, once we are aware of them, to dismiss many metaphysical possibilities. We take it for granted that we are not brains in vats, or living in the Matrix, or in an extended dream. Call these things that we take for granted “anti-skeptical assumptions”. What should a reflective agent who believes these things think of these beliefs? For various reasons, it can seem that we do not have evidence for such anti-skeptical assumptions. Are anti-skeptical assumptions, then, beliefs that one may rationally hold without evidence for them – indeed, even in the face of a positive judgment that one lacks evidence for them? I survey and criticize some prominent answers to this question, and then o...