This chapter takes an historical perspective on exploring the interrelationships between mind and body in the etiology and pathogenesis of physical as well as mental disorders and is presented in three parts. It begins with a review of earlier theories and the empirical context from which they emerged. Part 1 roughly covering 1940-1960 and Part 2, 1955-1972. Part 3 begins with the conclusion that it is not possible at this time to construct a satisfactory and empirically sound general theory of etiology and pathogenesis. (68 pp.)