R.M. Hare's new book, Freedom and Reason, is a welcome contribution to modern moral philosophy and should be read with care by anyone who believes that ethics should be relevant to the moral life, and that reason should have a substantial role to play in that life. Freedom and Reason, though not simply a sequel to Hare's earlier work, The Language of Morals, should be read with the earlier work in mind. This is important, not only because it presupposes some of the conclusions of that work, but also because of the strong criticism which the earlier work provoked, and which Freedom and Reason to a large extent answers.