The question Skinner puts before us is—what is the subject matter of psychology to be?
Skinner pointed out that since ancient times the answer to this question is—the subject matter of psychology is mental life, observed through introspection and revealed through self-report. This orientation—called mentalism—can be found in ancient Greek, Indian and Chinese philosophies. This orientation can be found in nearly all religions. In the Hebrew Testament Joshua exhorts us (24: 1-3) to “choose thou this day whom ye will serve.” It is explicitly stated in the Roman Catholic Act of Contrition that we “choose to do wrong” and “fail to do good.” This orientation is also found in the legal system. Citizens bear the responsibility to obey or break the law. Whichever option we choose, the responsibility is on us.
This orientation is found throughout the history of psychology. It’s found in the psychodynamic theories of personality (Freud and company), in Wundt’s structuralism and in McDougall’s hormic psychology. Whether the focus is religious, legal or psychological, in mentalism “to know thyself” means to know one’s thoughts and feelings.
In mentalism thoughts and feelings are held to be the causes of behavior. Thoughts and feelings are given primacy because they appear to precede and direct behavior. (Interestingly, we rarely consider the opposite, that behaviors and external conditions determine thoughts and feelings.) “I want an orange,” I think before walking to the refrigerator. “I want a linzer cookie,” I think before driving to the bakery. In Social Interest: A Challenge to Mankind (1938), Alfred Adler was explicit—“I am convinced a person’s behavior springs from his ideas.” C.S. Lewis wrote that we seem to have “inside information” when it comes to our behavior. Our minds appear to look out over our behavior, as a captain looks out over the bow of his vessel. The mind is on the bridge and steering. Behavior is on the poop deck and rowing.
Skinner delighted in pointing out that mentalism was pretty much a dead end. Plato would have no trouble understanding the non-neuroscience chapters of a twenty first century textbook in psychology. The atomists Democritus and Epicurus wouldn’t understand a word in a twenty first century textbook on physics, even if it was translated into ancient Greek.
Skinner believed that there has been little progress in psychology (other than in his branch of behaviorism) because psychologists have been looking in the wrong direction for the causes of behavior. Psychologists have been looking inside the organism for the causes of behavior. They should be looking outside the organism for the causes of behavior. They should be looking toward the environment, specifically toward the environment as it selects behavior.
Skinner didn’t use the term, but we can understand this issue using the social psychological concept of the fundamental attribution error (Fritz Heider). This is the idea that in attributing causation we can focus on the person or on the situation (environment). We can say a person did such-and-such on account of his or her personality. Or we can say a person did such-and-such because the environment made him or her do so. Like Skinner, social psychologists believe that most people, psychologists included, overestimate the importance of personality and underestimate the importance of the situation.