In this volume, R. M. Hare has collected a number of essays which fill in the theoretical background of his thought and which together give an overall picture of his views on a variety of questions. Each essay is self-contained, and topics covered include the objectivity and rationality of moral thinking, the issue between the ethical realists and their opponents, the place in our moral thought of appeals to common convictions, and how to tell whether a feature of a situation is morally relevant. His central theme is the paradox that, if moral judgements were just statements of fact, relativism would be inescapable. We can treat moral thinking as a rational activity only because moral judgements are more than this.