This landmark theory of interpersonal relations and group functioning argues that the starting point for understanding social behavior is the analysis of dyadic interdependence. Such an analysis portrays the ways in which the separate and joint actions of two persons affect the quality of their lives and the survival of their relationship. The authors focus on patterns of interdependence, and on the assumption that these patterns play an important causal role in the processes, roles, and norms of relationships. This powerful theory has many applications in all the social sciences, including the study of social and moral norms; close-pair relationships; conflicts of interest and cognitive disputes; social orientations; the social evolution of economic prosperity and leadership in groups; and personal relationships.

I: Introduction the Study of the History of Ideas; II: The Genesis of the Idea in Greek Philosophy; III: The Chain of Being and Some Internal Conflicts in Medieval Thought; IV: The Principle of Plenitude and the New Cosmography; V: Plenitude and Sufficient Reason in Leibniz and Spinoza; VI: The Chain of Being in Eighteenth-Century Thought, and Man's Place and Role in Nature; VII: The Principle of Plenitude and Eighteenth-Century Optimism; VIII: The Chain of Being and Some Aspects of Eighteenth-Century Biology; IX: The Temporalizing of the Chain of Being; X: Romanticism and The Principle of Plenitude; XI: The Outcome of The History and Its Moral