Abstract

The final chapter of the dissertation applies the resources of the Janusian account in appraising the case study. This application demonstrates that the development of evolutionary psychology and behaviorism was rational and that the development of behaviorism is best understood as a case of strategic change. ;Chapters II, III and IV provide an historical case study of the development of evolutionary psychology and behaviorism. Chapter II presents Darwin's explorations of the domain of animal activity. Particular attention is given to his attempt to disengage the context of natural theology and develop a naturalistic theory which allows for a full interaction of inherited and acquired characteristics. His theorizing gave rise to a set of problems which provided a focus of research for evolutionary psychology. Chapter III examines the solutions to these problems offered by Spalding, Romanes and Morgan. Spalding empirically demonstrated the existence of instinct and developed the naturalist's maxim. Romanes organized the domain of inquiry, specified a mechanism for the performance of instinct and developed an account of learning. Morgan provided a new methodology for the study of animal activity, developed a new mechanism for the performance of instinct, constructed a purely selectionist theory of the evolution of instinct and presented a trial and error theory of learning. The second and third results of Morgan's research are of particular importance. Both involved the use of interdisciplinary criticism; the former owing to Sherrington's research, the latter, to Weismann's. Chapter IV examines the development of behaviorism and the generation of a new strategy for the study of animal activity. Thorndike introduced the notion of systematic experimentation and formulated several psychological laws of learning. Thorndike, Angell and Watson each attempted to specify the domain of psychology in behavioral terms. Finally, Watson explicitly formulated a new strategy. Within this new strategy the experimental analysis of the acquired component of animal activity was the focal point of research. It is important to notice that this new focus is at least in part a result of Watson's understanding of the interdisciplinary criticism provided by Johannsen's research in genetics. ;In Chapter I a Janusian account of scientific rationality is developed. This account is based on the philosophic theories of I. Lakatos and S. E. Toulmin. The Janusian account preserves the similarities between the two theories, interprets Lakatos' retrospective and Toulmin's prospective appraisals as complementary and provides resources for expanding their individual accounts. In particular the Janusian expansion includes a narrow and a broad sense of rationality, a fine structure for supertheoretic principles and analyses of interdisciplinary criticism and strategic change. ;Was Watson's behaviorism an extension of Darwin's evolutionary psychology or a successor to it? This dissertation claims that behaviorism was neither; rather it was a strategic change in the study of animal activity. In order to support this claim both philosophical and historical analyses are presented