Edward C. Tolman (1886-1959) was an American psychologist, who received his Ph.D. in psychology in 1915. He had been trained in Wundt’s experimental psychology and also studied with Kurt Koffka, who was a founder of the new Gestalt psychology.
While still a graduate student, Tollman had been significantly influenced by Watson’s (1913) espousal of classical conditioning and the emerging model of behaviorism. Both gestalt psychologists and behaviorists were highly critical of Wundt’s introspection, which Tolman soon abandoned.
A major influence on Tolman was one of his teachers, E. B. Holt (1873-1946), a behaviorist who did not accept Watson’s rejection of consciousness. Holt believed consciousness and other internal events, such as hunger and thirst, could be experimentally related to observable physical events. He conceptualized some of these internal events as drives, thus anticipating later research in motivation. Holt believed that one should study much larger behavioral units than Watson’s S-R units--larger units that accomplish some purpose and achieve some goal, such as a hungry animal solving a problem to obtain food.
Tolman studied animal learning in the laboratory using the Pavlov-Watson conditioning model. However he soon became critical of Watson’s behaviorism, and went on to form a new version, which he called purposive behaviorism. In this we see the influence of his earlier study of Gestalt psychology and of Holt’s formulations. Tolman maintained the behaviorists’ focus on objective experimentation, behavior, and stimulus conditions. Like other behaviorists, he rejected the subjectivism of the structuralists and their focus on consciousness. He observed, however, as did Holt, that there is purpose (also called goal-orientation) in the behavior of animals and humans, a point on which Watson strongly disagreed. Watson believed that to suggest purpose is to imply consciousness, and the rejection of consciousness is basic in Watson’s model. Tolman’s contribution was to bring the recognition of purposive behavior into the behaviorist paradigm, without slipping back into subjective concepts and procedures.
In Tolman’s model, as for all behaviorists, the basis of behavioral study must be observable fact. For Tolman, behavior is initiated by combinations of five independent variables, each of which can be manipulated experimentally. These initiators are environmental stimuli, physiological drives, heredity, previous learning, and age.
Tolman inferred that between the initiating variables and the overt behavior there are intervening variables--that is, such factors as hunger that occur internal to the organism. Here, again, we see Holt’s influence. Tolman believed that these intervening variables are the actual determinants of behavior. Thus, Watson’s S-R paradigm is changed to Tolman’s S-O-R paradigm (Stimulus-Organism-Response).
In both animal and human research, we can specify, observe, and measure the dependent variable (behavior), and can specify, observe, measure, and experimentally manipulate the independent variables (stimuli, previous learning, etc.). Although the intervening variables cannot be directly observed, we can operationally define them by tying them to observed dependent variables and to the manipulated independent variables. In this way, any intervening variables specified by the theory--for example, hunger, need, drive, curiosity, or fear--can be objectively, although not directly, studied.
The Gestalt influence on Tolman is evident in his inferences about the nature of those intervening variables. He speculated that organisms, in problem solving tasks, such as maze-running, develop cognitive maps and expectancies of what will be found, such as food. The cognitive maps represent an appreciation of the general conditions of the task. It is these cognitive constructs that intervene between stimulus and response, accounting for performance and learning. Tolman called his model field theory to emphasize its focus on large units of behavior and distinguish it from the more molecular S-R model. Field theory is mainly associated with Kurt Lewin and the Gestalt psychology movement. We see its obvious influence on Tolman.
Tolman integrated concepts from behaviorism, Gestalt psychology, and cognitive psychology. He is a predecessor of cognitive-behavioral therapy, which emerged a generation later. Among Tolman’s important publications were Purposive Behavior in Animals and Men (1932), A Stimulus-Expectancy Need-Cathexis Psychology (1945), and Autobiography (1952).