The present argument is this: mental life and the world in which it is lived are inventions. They have been invented on the analogy of external behavior occurring under external contingencies. Thinking is behavior. The mistake is in allocating the behavior to the mind. ~ B.F. Skinner
American behavioral psychologist B.F. Skinner (1904–1970) was a prolific author. He was also convincing. Skinner is widely regarded as the most influential psychologist of the 20th century.
Skinner trained experimental animals via what he termed operant conditioning. While so-called classical conditioning dealt with reflexes, operant conditioning was of voluntary behaviors. Operant conditioning employed reinforcement and punishment to respectively strengthen or lessen a specific behavior.
The consequences of an act affect the probability of it’s [sic] occurring again. ~ B.F. Skinner