Leon Festinger, Henry W. Riecken, Stanley Schachter

Leon Festinger (8 May 1919 – 11 February 1989) was an American social psychologist who originated the theory of cognitive dissonance and social comparison theory. The rejection of the previously dominant behaviorist view of social psychology by demonstrating the inadequacy of stimulus-response conditioning accounts of human behavior is largely attributed to his theories and research. Festinger is also credited with advancing the use of laboratory experimentation in social psychology, although he…