ABSTRACT
Experimental subjects are sentient, active, cognizing, persons whose perceptions, attitudes, and expectancies may integrally affect the nature of experimental outcomes. No subject taking part in a study is motivationless and subjects are rarely, if ever, neutral to an experimental outcome. Insofar as they care about the outcome, their perceptions of the role and of the hypotheses being tested may be significant determinants of their behavior. Neisser ( 196 7) has noted that the procedures of experimental psychology tackle the problem of knowing what the subject is trying to do by sheer brute force. In any routine learning experiment, for instance, the subject is assumed to be motivated by the single motivation of "getting on with the experimental task," and solving what he is asked to solve. The richness and variety of response so characteristic of ordinary life is assumed to be absent even in experiments where higher mental processes are obviously involved.
