In these three Tanner lectures, distinguished ethical theorist Allan Gibbard explores the nature of normative thought and the bases of ethics. In the first lecture he explores the role of intuitions in moral thinking and offers a way of thinking about the intuitive method of moral inquiry that both places this activity within the natural world and makes sense of it as an indispensable part of our lives as planners. In the second and third lectures he takes up the kind of substantive ethical inquiry he has described in the first lecture, asking how we might live together on terms that none of us could reasonably reject. Since working at cross purposes loses fruits that might stem from cooperation, he argues, any consistent ethos that meets this test would be, in a crucial way, utilitarian. It would reconcile our individual aims to establish, in Kant's phrase, a 'kingdom of ends'. The volume also contains an introduction by Barry Stroud, the volume editor, critiques by Michael Bratman (Stanford University), John Broome (Oxford University), and F. M. Kamm (Harvard University), and Gibbard's responses.T HE BERKELEY TANNER LECTURES The Tanner Lectures on Human Values, which are presented annually at each of nine universities in the United States and Great Britain, are among the most prestigious and notable events of the academic year. This volume is the latest in a new interdisciplinary series of books based on the Tanner Lectures given at the University of California, Berkeley. The series aims to make these distinguished lectures, and the lively debates stimulated by their presentation in Berkeley, available to a broad readership.