This book provides a radical alternative to naturalistic theories of content, and offers a new conception of the place of mind in the world. Confronting head-on the scientific conception of the nature of reality that has dominated the Anglo-American philosophical tradition, Michael Morris here presents a detailed analysis of content and propositional attitudes, based on the idea that truth is a value. In the course of this analysis, he rejects the causal theory of the explanation of behaviour and replaces it with an alternative which depends upon a rich conception of the behaviour we explain with reference to states of mind. According to the theory presented here, our understanding of other people is inextricably involved with our evaluation of what they do, and the objectivity of truth depends on the objectivity of moral goodness. Dr Morris's lucid and detailed exposition of his controversial argument sounds an emphatic challenge to the naturalistic orthodoxy in areas as diverse as metaphysics, ethics, and cognitive science.