The purpose of this Introduction is to sketch our approach to the study of value, morality and action, and to show the place we assign it in the system of human knowledge. 1. VALUE, MORALITY AND ACTION: FACT, THEORY, AND METATHEORY We take it that all animals evaluate some things and some processes, and that some of them learn the social behavior patterns we call 'moral principles', and even act according to them at least some of the time. An animal...