Why do we want to justify our decisions, even if they appear to be irrational? The answer lies in cognitive dissonance, the mental discomfort we experience when we hold two contradictory beliefs at the same time. In A Theory of Cognitive Dissonance, first published in 1957, American social psychologist Leon Festinger investigates the problem. Festinger puts forward the idea that we have developed mechanisms to try to deal with the stress brought on by cognitive dissonance.
Published in 1974 in the journal Science, the article Judgment Under Uncertainty had a profound impact across the social sciences. Two relatively young Israeli psychologists were challenging the leading ideas about human thought. For decades, social scientists had used a mythical figure to describe how humans make decisions: homo economicus. Homo economicus was logical and conscientious.