Reinforcement Theory

Mahzarin R. Banaji
Richard Clarke Cabot Professor of Social Ethics, Faculty of Arts and Sciences

To B.F. Skinner, the observables of behavior — whether it be the measurable peck of a pigeon’s beak or the bar press of a rat’s paw — constituted the only legitimate foundation on which a science of psychology could be built.

The Harvard professor emphasized the importance of “orderly data” and repeatedly refined his methods in order to make for systematic evidence. His methods, the most famous of which is the eponymous Skinner box, enabled the precise timing of events and the objective recording of responses, giving psychology the paraphernalia typical of the older natural sciences.

In understanding why any organism behaves the way it does, Skinner saw no place for dwelling on a person’s “intentions” or “goals.” For him, it was outward behavior and its environment that mattered. His most important contribution to psychological science was the concept of reinforcement, formalized in his principles of operant conditioning (in contrast to Ivan Pavlov’s principles of classical conditioning, which along with J.B. Watson’s extreme environmentalism strongly influenced his own thinking).

Behavior increases in probability when its outcomes are reinforced. In other words, a behavior such as a smile or even a complex pattern of behavior (e.g., superstitious behavior) occurs because similar previous responses have been rewarded in particular contexts. Of course, behavior had to be broken down into smaller steps to achieve optimal reinforcement, and each step had to receive feedback to shape new and highly complex strings of behavior.

By Skinner’s standard, very little of today’s science of psychology would be regarded as scientifically legitimate. Looking at the human mind itself, which has been psychology’s primary focus since the cognitive revolution, simply horrified him. But while psychology has moved in new directions, Skinnerian procedures have been effectively applied to the understanding and modification of human behavior in contexts such as industry, business, government, education, prisons, and mental institutions. His work also provided insight into methods by which children are raised, with specific applications to attachment and separation distress, crying, imitation, social referencing, and the acquisition of skills.