Rüdiger Bittner argues that the aim of thinking about what to do, of practical reason, is to find, not what we ought to do, but what it is good to do under the circumstances. Neither under prudence nor under morality are there things we ought to do. There is no warrant for the idea of our being required, by natural law or by our rationality, to do either what helps us attain our ends or what is right for moral reasons. While common moral understanding is committed to there being things we ought to do and to our being guilty and deserving blame if we fail to do them, we can lay aside these notions without loss, indeed with benefit. The volume also explains what it is for something to be good to do under the circumstances and argues for understanding practical reason in these terms. What is good to do we find by experience: what we go through teaches us what helps and what hinders, and helps us figure out what is prudentially useful and what is morally right to do-although ultimately this difference itself gives way, and morality turns out to be a part of prudence.