Moral disagreements are not hard to find. Some rest on simple misunderstandings, but others are deep, resisting serious attempts at thoughtful resolution. Disagreements are often socially distressing; but for those who share with Thomas Reid (1872, pp. 586b-99b) a belief in moral facts (Shafer-Landau, 2006) and a common moral sense (Roeser, 2005; Cuneo, 2003), moral disagreements are ... [Show full abstract] epistemologically distressing as well. In this essay, I will assess Reid’s resources for answering some of the questions that arise from the evidence of deep moral disagreement. Elsewhere I have argued that Reid could have answered these questions without abandoning any of his central claims (Davis, 2006, chap. 7). Here I will significantly qualify that conclusion. I will show that Reid’s ability to answer these questions is limited by his pursuit of a broadly Enlightenment project. Following Maclntyre (1990) and others, I will refer to this limitation as Reid’s “encyclopaedist” commitments (Pakaluk, 2002, p. 564; Poovey, 2002, p. 125). Reid can turn back challenges from moral disagreement that attack overly simplistic versions of his moral sense theory. Nevertheless, the confidence pervading his approach to moral knowledge cuts off strategies for responding to moral disagreements that resist simple rational resolution. I will argue that it would have been easier for Reid to defend his moral sense theory against the challenge of moral disagreement if he had embraced a Scottish Calvinist approach rather than encyclopaedist principles.