Psychophysical Research

To the Editors:

A central point in D. W. Harding’s excellent review The Eyes Have It (NYR, April 22) concerns the research strategy Savage proposes for psychophysics. This deserves amplification with two further comments.

First, the three-step plan put forward by Savage (involving measurement of physical stimuli; measurement of perceptual responses to these stimuli; and statistical analyses of the relationship between these two sets of data) is virtually identical to the methodology elaborated, demonstrated, and discussed by Egon Brunswik in publications dating back to the 1940s and ’50s. Brunswik’s Perception and the Representative Design of Experiments (University of California Press, 1956) is especially relevant. But Brunswik’s ideas were not accepted by most psychologists of his time, partly because his writing style was difficult to follow, and more importantly because he was criticized by influential theorists such as Clark Hull for postulating an “empty organism.”

This is not to criticize the contribution of Savage, however. Although he reaches the same conclusions as Brunswik did, he states them very well and bases them upon a broader body of accumulated research. It is, nevertheless, quite striking to see Harding praise Savage for the very same idea (viz.: omitting an intervening psychological dimension between physical stimuli and perceptual responses) that brought heavy criticism upon Brunswik.

Second, it should be mentioned that an increasing number of researchers in the field of perception, experimental psychology and social psychology have been working for some time according to what might be called the Brunswik-Savage position. Some of us—most notably Kenneth Hammond at the University of Colorado—have used Brunswik’s ideas as the basis for studies of social perception, decision-making, and human judgment in general, and we have found multiple regression statistics to be a valuable tool for understanding certain individual thought processes, which in turn heavily influence such social processes as group decision-making and interpersonal conflict.

Yet as one does this sort of work (see Human Judgment and Social Interaction, L. Rappoport and D. Summer, eds., Holt, Rinehart & Winston, in press) it becomes apparent that there is no need to simply by-pass the organism while establishing mathematical relationships between stimuli and responses. Useful as this strategy may be heuristically, because it opens a clear basis for the deployment of statistical techniques, its acceptance does not preclude study of how human values may influence perception or the higher order judgment processes involved in more complex forms of decision-making. Instead, our work suggests that we have to understand these things in a new way.

Brunswik himself anticipated the joining of perception and cognition theories in a little known essay concerning the contributions of Jean Piaget. Some of us working in related research areas today hope that we will soon be able to offer strong empirical support for Harding’s suggestion that “we may have altered our view of the kind of structure that the living organism is.” Unfortunately, the thing is going to be pretty damned difficult because of the resistance generated from longstanding theoretical perspectives which are still thought to be entirely contradictory.

Leon Rappoport

Department of Psychology

Kansas State University

Manhattan, Kansas