ABSTRACT
The term “positivism” has come to embrace so many different issues that it defies simple definition. As Raymond Williams has noted, it is now hardly more than a “swear word, by which nobody is swearing” (Williams, 1983,p. 239). Indeed, in recent psychology, and especially social psychology, the term is identified with the very idea of an experimental psychology. There have been two episodes in the history of psychology, however, where the methods (and prestige) of experimental science were themselves directed against some of the main foundations of positivism in psychology, and Michotte participated, as a significant figure, in each of these developments. The first was the Würzburg research of Külpe and his students on “imageless thought”; their work explicitly challenged the sensationalist assumption of posi-tivistic psychology by showing that human awareness is not restricted to sensory contents. The second challenge to positivism involved the psychology of perception, and was directed, to a remarkable degree, against a single assumption of traditional theory, the “constancy hypothesis.” According to this hypothesis, the sensory effects of local stimulation are supposed to be fixed, and hence uninfluenced by the wider context. The Berlin Gestaltists (Wertheimer, Köhler, and Koffka) tend to be given the main credit for this particular challenge to the atomistic and mechanistic basis of positivistic psychology, yet, in fact, it involved a much wider and disparate group of researchers (including Rubin, Katz and Michotte).
