Why be moral? Philosophers have wanted to answer this question for well over two thousand years, ever since Plato wrote on the subject. The question turned out to be as frustrating as it is compelling. A proper philosophical answer begins by saying what morality is, and what it means to be moral. A wise philosophical answer also steps back to ask what sort of being wants an answer. Why are we asking? Who wants to know? What do we want, and in what way might being moral serve our purposes? What difference does it make whether we have any reason to be moral? Do we have reason to care whether other people have any reason to be moral? Why? In this book, David Schmidtz presents elements of a theory of humanly rational choice: why we have reason to be rational, why being rational about the big picture seldom involves maximizing our payoff on a day to day basis, how rational agents choose ends, and why rational agents choose to respect and care about other people. Schmidtz also presents elements of a theory of morality: how being moral connects to what is good for oneself and to what is good for others, how it connects to following rules and understanding what the people around us expect from us, and how it connects to the heights of human aspiration and flourishing.