The document discusses the behaviorist theory of learning proposed by theorists Ivan Pavlov, B.F. Skinner, and John Watson. Pavlov is known for his experiments with Pavlov's dogs and the concept of classical conditioning. Skinner introduced operant conditioning and the Skinner box. Watson proposed the theory of behaviorism and conducted experiments on conditioning emotions, such as with Little Albert. The behaviorist theory views learning as the acquisition of behaviors based on environmental stimuli and reinforcement or punishment.