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A scientific perspective which specifies that events occur in completely predictable ways as a result of natural and physical laws.

Since ancient times, the origins of human behavior have been attributed to hidden or mystical forces. The Greek philosopher Democritus speculated, for example, that objects in our world consist of atoms; included among these "objects" was the soul, which was made of finer, smoother, and more spherical atoms than other physical objects. He rejected the concept of free will and claimed that all human behavior results from prior events. Some philosophers have advanced the argument that human behavior is deterministic, although most have resisted the idea that human beings merely react to external events and do not voluntarily select behaviors.

There is a clear dilemma in explaining human behavior through psychological principles. On the one hand, if psychology is a science of behavior, then there should be laws allowing the prediction of behavior, just as there are gravitational laws to predict the behavior of a falling object. On the other hand, objections have been raised by individuals who believe that humans control their own behaviors and possess free will. Part of the controversy relates to the concept of the mind and body as separate entities. In this view, the mind may not be subject to the same laws as the body. Wilhelm Wundt (1832-1920) attempted to make the distinction between determinism and indeterminism by suggesting that psychological processes could be creative and free, whereas the physiological processes in the brain were deterministic. This argument does not solve the problem for psychology, however, because psychologists consider mental processes appropriate for study within a scientific framework, thus subject to scientific laws.

Other psychologists like William James, who was interested in religion and believed in free will, recognized this conflict but was reluctant to abandon the concept that behaviors were not free. At one point, he suggested that mind and body operated in tandem, whereas on another occasion he concluded that they interacted. Clearly, James struggled with the issue and, like others, was unable to resolve it. The behaviorists were the most obvious proponents of determinism, dating back to John B. Watson, who claimed that environment was the single cause of behavior, and who made one of the most famous deterministic assertions ever: "Give me a dozen healthy infants … and my own specified world to bring them up in and I'll guarantee to take anyone at random and train him to become any type of specialist I might select—doctor, lawyer, artist, merchant, chief, and, yes, even beggar man and thief."

The psychologist with the greatest influence in this area, however, was B. F. Skinner. He adopted a stance called radical behaviorism, which disregarded free will and the internal causes of behavior. All behavior, Skinner maintained, was determined through reinforcement contingencies, that is, the pattern of reinforcements and punishments in an individual's life. Although critics have claimed that Skinner's concept of determinism denied people of their humanity, he maintained that his approach could actually lead to more humane societies. For example, if people were not responsible for negative behaviors, they should not be punished, for they had no control over their behaviors. Instead, the environment that reinforced the unwanted behaviors should be changed so that desirable behaviors receive reinforcement and increase in frequency.

Sigmund Freud defined determinism in terms of the unconscious and contended that behavior is caused by internal, mental mechanisms. In some ways, Freud was more extreme than Skinner, who acknowledged that some behaviors are not predictable. The main difference between Freud and Skinner involved the origin of causation; Freud believed in underlying physiological processes while Skinner opted to focus on external causes. Thus, even though Freudians and Skinnerians differ on almost every conceivable dimension, they have at least one commonality in their reliance on determinism.

Those scientists who believe that behaviors are determined have recognized the difficulty in making explicit predictions. Thus, they have developed the concept of statistical determinism. This means that, even though behaviors are determined by fixed laws, predictions will never be perfect because so many different factors, most of them unknown, affect actions, which result in generally accurate predictions. The recently developed theory of chaos relates to making predictions about complex events such as behaviors. This theory suggests that in a cause-effect situation, small differences in initial conditions may lead to very different outcomes. This theory supports the notion that behaviors may not be completely predictable even though they may be dictated by fixed natural laws.

Further Reading

Doob, Leonard William. Inevitability: Determinism, Fatalism, and Destiny. New York: Greenwood Press, 1988.

Additional topics

Psychology EncyclopediaPsychological Dictionary: Kenneth John William Craik Biography to Jami (Mulla Nuruddin ʼAbdurrahman ibn-Ahmad Biography