MATERIALISM. As a philosophical doctrine, materialism can be given a deceptively simple definition: the view that matter is all there is. The simplicity is deceptive because, of course, the term matter can itself be understood in so many different ways. It is more illuminating, perhaps, to define materialism in terms of what it denies. It excludes the existence of entities that are radically different in kind from, and in some sense superior to, the matter of our ordinary experience. It rejects, therefore, a God or gods on whom the universe would depend for its existence or mode of operation; it denies the existence of angels or spirits that can affect the material order while ultimately escaping its limitations; it questions the notion of a soul, if taken to be an immaterial entity separable in principle from the human body it informs. Its two main targets are, therefore, theism...