The essays in this volume consider the question of whether the self is a unity or whether it should be conceived without metaphor as divided–as a multiple self. The issue is a central one for several disciplines. It bears directly on the account of rationality and the explanation of individual decision-making and behavior. Is the hypothesis of a multiple self required to deal with the problems of self-deception and weakness of will; and can the conceptual tools developed in the study of interpersonal conflict be applied to the analysis of intra-personal struggle? The essays, by a number of leading philosophers, psychologists, and economists, were all commissioned for this volume.