Professor Monro presents an original view of ethics based on empiricism, which leads him to a subjectivist position about moral values. He starts by examining the central problem in moral philosophy: are moral statements objectively true, or are they expressions of preference? The first view conflicts with the empiricist beliefs current in modern thought; the opposing naturalistic theory seems to lead to moral scepticism. After discussing both views, the author presents a detailed defence of the subjectivist position. In the course of his argument he gives a detailed analysis and criticism of the 'universalisability thesis', the theory that moral aspirations differ from others in being applicable to all men, and that it is this that makes them moral. He then offers an alternative account of the nature of moral attitudes. The author illustrates his explanations with straightforward analogies and examples. His clear exposition of the fundamental concepts arising in his argument makes this a book for students as well as for professional moral philosophers.