This book propounds a theory of reason and a theory of morality, advanced by Professor Baier in his APA presidential address and his Carus Lectures. Our possession of reason and our ability to reason depend on our having grown up in a rational order: a social order which engages in the enterprise of reason and, through socialisation, passes on from one generation to the next the knowledge of the recognised general principles of reasoning, the ability to apply them to particular cases, and the methods for further improvement. Two kinds of practical reason can be distinguished, the "self-anchored" and the "society-anchored", the second being by its nature paramount over the first. Much of this is also true of morality because, Baier argues in detail, the moral enterprise is the same as that of society-anchored reason. "The Rational and the Moral Order" sets out original arguments for a number of controversial claims. Moral directives imply that they are themselves sound, and therefore pass a certain test, and can be said to be true or false. Purported conceptions of morality are genuine only if they construe moral judgements as capable of being sound or unsound. Sound moralities are society-relative, and it can be shown that sound moral reasons are always paramount over reasons of self-interest.