 In his discussion of the principles of common sense, Reid presents various first principles, including the claims that memory is reliable and that those things exist that we distinctly perceive. Although sometimes he seems to claim that our particular perceptual judgments are derived from them, a closer look at what Reid says makes it clear that this is not his considered view. For, in Reid’s view, ordinary perceptual judgments are formed non-inferentially and are not self-evident. What role, then, do these principles of common sense play? Nicholas Wolterstorff (2001, Ch. IX and 2004) argues that Reid thinks of such principles as being similar to what Wittgenstein, in On Certainty, called “framework propositions.” They are propositions that ordinary people do not typically explicitly believe but rather take for granted in their everyday comings and goings. Similarly, one might hold that, properly understood, Reid’s view is that the moral first-principles are not propositions that ordinary agents who have received a decent moral education ordinarily consciously believe at some time or other. Rather, they are what these agents take for granted in their moral deliberations; they form the horizon or background against which they deliberate—although these agents would, presumably, assent to them if they were explicitly presented (for an alternative but, in principle, complimentary account, see Davis 2006, Ch. 6).