Robert A. Wilson

Individualism in psychology is the view that mental states must be individuated so as to be intrinsic to particular individuals. This view has been thought to impose an intuitive and plausible constraint on explanation in psychology. The dissertation is a sustained examination of individualism, especially with respect to its role in psychological explanation. My particular interest is in showing that individualism is not a constraint on psychology which follows from either psychology's scientific nature, or from the nature of causation or materialism. ;Apart from an extended introduction in which I explain why individualism is both a substantive and plausible constraint on taxonomy and explanation in psychology, the dissertation has three parts. The aim of Part One is to reconstruct and critically discuss three influential, recent arguments for individualism: an a priori argument , a empirical argument , and a methodological argument. I argue that each of these arguments is unsound and should be rejected. In an Appendix to Chapter 2 I argue that individualism does not follow from the causal theory of properties. ;In Part Two I turn to examine individualism itself. The aim of this part of the dissertation is to address the view that psychological kinds and explanations which are not individualistic cannot be part of an adequate account of mental causation. Chapter 5 both responds to particular charges that have been made about denials of individualism, and articulates and criticizes a central intuition about the local nature of causation from which individualism has sometimes been thought to follow. Chapter 6 focusses on folk psychology and attempts to show how one can view folk psychological explanation as unproblematically causal even though it is not individualistic. ;In Part Three I develop a core case against individualism using the concepts of causal depth and theoretical appropriateness, concepts which form the basis for two constraints on good causal explanations. I argue that individualism should be rejected because individualistic explanations of behavior, including individualistic psychological explanations, are not always the causally deepest or most theoretically appropriate explanations available.