What defines the very character of science is not the mechanical application of one or another method, but a much larger narrative in which methods are chosen because of their transparent relevance to a widely perceived problem. The methods adopted by Archimedes in ancient Greece, Newton in seventeenth-century England, Darwin in the middle of the nineteenth century, and Einstein early in the twentieth have very little in common at the descriptive level. In a word, there is no single scientific method at all. There is, however, a quite systematic relationship between the identification of a problem of scientific consequence and the subsequent choice from among available methods of observation and measurement. What establishes this relationship is a theory rich in ontological or in explicative possibilities. A theory rich in ontological possibilities is one which, when found to be valid, clarifies and may even reduce the domain of really existing entities. We no longer believe that heated objects rise because, as a result of heating, they take on a substance called “levity.” We no longer explain phenomena by referring to the properties of phlogiston.
The history of experimental psychology has not followed the pattern of the developed sciences and has deviated from the pattern by ever wider margins with the passage of time. Just what overarching theory is tested by contemporary experiments in psychology? What problem has been solved? What effect have psychological hypotheses or findings had on the size and nature of the ontological domain in which all genuinely psychological phenomena are to be found? What has been characteristic of experimental psychology is the adoption of a rather prosaic set of experimental “controls” and a repeated-measures paradigm. In a wide variety of settings, this method of procedure has yielded fairly stable functional relationships between dependent and independent variables under conditions generally so unlike the domain of interest as to render generalizations jejune. It is a credit to the psychologists of the nineteenth century that they valiantly undertook to apply such methods to psychological phenomena, for only by attempting to develop psychology in such a fashion could the limits of the method be assessed. It is less of a credit to the legions that have dutifully imitated these efforts for the better part of a century.
Daniel N. Robinson, An Intellectual History of Psychology, 3rd ed. (Madison: University of Wisconsin, 1995), 331–332.