Festinger, Leon

Festinger, Leon

(1919–89) social psychologist; born in New York City. Educated at the State University of Iowa, he taught at Rochester University, the Massachusetts Institute of Technology, and the Universities of Michigan and Minnesota. At Stanford University (1955–68), and the New School for Social Research (1968) he was increasingly recognized for his theory of cognitive dissonance, whereby people are unable to tolerate conflicting thoughts and beliefs over time and must resolve such conflicts by rejecting or devaluing one or more of the cognitions. His major work was A Theory of Cognitive Dissonance (1957).