John B. Watson – 1878-1958

In his 1913 essay “Psychology as a Behaviorist Views It,” Watson defined psychology as the science of human behavior, which could and should be studied in the laboratory with scientific rigor—just as one would study the behavior of animals. Watson went on in other works to codify behaviorism as the objective experimental study of the relation between environmental stimuli and human behavior. This approach dominated psychology in America throughout the 1920s and 1930s.