Published online by Cambridge University Press: 14 March 2022
An attempt is made to provide a statement of the sufficient conditions for the functional equivalence of observable events in Psychology. Without a statement of those conditions, no explanation of functional equivalence in empirical situations can be achieved. A characterization of functional equivalence strictly in terms of the traditional S–R language is examined. This characterization is found to be inappropriate in that it entails vacuous mediators. A revision of S–R language is attempted in order to characterize functional equivalence. While this account does not entail vacuous mediators, it is unsatisfactory since it cannot be stated naturally in terms of the S–R language. It is argued that the degree to which the conditions for functional equivalence can be appropriately and naturally stated in theoretical languages provides a criterion for choosing among them as theoretical languages for psychology. A statement of the conditions for functional equivalence in terms of a TOTE analysis (see [5]) is then given. This is found to be more satisfactory than both the traditional and modified S–R analyses in that it does not entail vacuous mediators and in that a natural characterization of functional equivalence can be achieved.
The author wishes to acknowledge his debt to his colleagues, Drs. C. E. Osgood, C. N. Cofer, and W. B. Weimer, for their criticisms and comments at various states in the writing of this paper. He does not want to indicate that they support any of the positions taken here, but only that they are responsible for the elimination of many of the paper's more glaring errors.