B.F. Skinner

Behaviorism
This theory asserts that behavior can be explained entirely in terms of observable responses to environmental stimuli. Influenced by the conditioned-reflex experiments of Pavlov, behaviorism was introduced in 1913 by J.B. Watson, who, denying both the value of introspection and the concept of consciousness, emphasized stimulus-response laboratory techniques. B.F. Skinner concerned himself exclusively with the relationship of observable responses to stimuli and rewards, and one result was the concept of mastery learning, which was applied in the 1950’s as “teaching machines”.