ABSTRACT
Several of the best physicists of the last half of the nineteenth century were also distinguished psychologists or physiologists. The contributions of Helmholtz, Maxwell, and Mach to perception are notable examples of this productive interdisciplinary activity (Boring [1950], Koenigsberger [1906], Campbell and Garnett [1882], Ratliff [1965]). Why then did not interdisciplinary studies, based on these inspiring successes, flourish at the beginning of the twentieth century?
