Behaviorism: principles, history, and applications

The initial spark of behaviorism is John B. Watson's famous article "Psychology as the Behaviorist views it" (1913), in which he vehemently spoke out against the method of introspection that was common in psychology at the time. Watson's aim was to re-found psychology as a natural science, as it were. He relied exclusively on the so-called "objective method" by breaking down all behavior into stimulus and response; this form of behaviorism is therefore also called "molecular" behaviorism. Watson regarded as a stimulus any change in the external environment or inside the individual that is based on physiological processes, e.g. also a "lack of food", i.e. hunger; he regarded as a reaction any activity, be it turning towards or away from a light source or writing books. The form of behaviorism founded by Watson is also called "classical" or "methodological" behaviorism.

The physiological processes underlying observable behaviour are considered uninteresting by the behaviourist; from his point of view, they belong to the field of activity of physiologists. The behaviorist focuses exclusively on processes that take place between the organism and the environment. The organism itself is regarded by the classical behaviorist as a black box.

Skinner's main work Science and Human Behavior was published in the USA in 1953. In contrast to Watson and methodological behaviorism, Skinner's so-called "radical" behaviorism did not exclude inner-psychic processes in the study of behavior. However, statements about "mental" or "psychological" processes could never be made by outsiders, i.e. independent observers, but at best by the individual observing himself. If, for example, a student unintentionally responds to a teacher's question with a completely inappropriate answer, the student's "inner state" is often described as absent-minded. In reality, however, this attribution in no way explains the states inside the brain; in fact, it is merely an additional, figurative description for the student's erroneous utterance, i.e., for the student's reaction that is already known to the observer anyway.

The representatives of a behaviourist science of behaviour therefore demanded that all processes that affect an organism in an experiment (i.e. the causes of behaviour) should also be described in strictly scientific terms; psychology had to become an "exact science" in the sense of a natural science (whereby Skinner oriented himself more to the scientific concept of biology than to that of physics). One of the consequences of this was that non-scientific influences on behavior (for example, from "social structures" or from "culture and tradition") played no role in the behaviorists' studies unless they were defined at the level of environmental influences and behavior. Laboratory studies became the most important means of their research, since only there a very extensive control of all factors influencing the behaviour of test animals and test subjects is possible, and especially the Skinner box, which was developed especially for behaviourist experiments. Moreover, laboratory studies can be repeated much more easily than the field studies preferred by ethologists.

The research tradition that builds on Skinner's Radical Behaviorism as a philosophy of science is Experimental Behavior Analysis.

The renunciation of the use of inner-psychic processes for the explanation of behaviour, which cannot be described with scientific terms, has brought behaviourism persistent heavy criticism. It considers the brain to be a mere black box that automatically responds to a stimulus. However, the exclusive analysis of the connection between input and output ignores the fact that there are internal, variable, centrally nervous drives for behaviour, which become ­noticeable, for example, as sexual desire and as a feeling of hunger.

Skinner rejects the "black box" metaphor. Mentalistic statements like "He eats because he is hungry" are, according to him, no explanations for behavior. In Science and Human Behavior he writes: "He eats and he is hungry describe one and the same fact. (...) The habit of explaining one observation by another is dangerous in that it gives the impression that we have got to the root of the cause and therefore need look no further." Skinner rejects the notion of a Cartesian helmsman who, as it were, sits inside the head steering man; man as a whole individual ("organism as a whole") behaves in a certain way ("molar behaviorism") because of the environmental influences to which he has been subjected in his present and past environment, as well as because of the environmental influences to which his ancestors have been subjected in phylogenesis.