Cognitive Dissonance

Cognitive dissonance is a psychological term which describes the uncomfortable tension that may result from having two conflicting thoughts at the same time, or from engaging in behavior that conflicts with one's beliefs. More precisely, it is the perception of incompatibility between two cognitions, where "cognition" is defined as any element of knowledge, including attitude, emotion, belief, or behavior.

The theory of cognitive dissonance states that contradicting cognitions serve as a driving force that compels the mind to acquire or invent new thoughts or beliefs, or to modify existing beliefs, so as to reduce the amount of dissonance conflict between cognitions. Experiments have attempted to quantify this hypothetical drive. Some of these examined how beliefs often change to match behavior when beliefs and behavior are in conflict.

Social psychologist Leon Festinger first proposed the theory in 1957 after the publication of his book When Prophecy Fails, observing the counterintuitive belief persistence of members of a UFO doomsday cult and their increased proselytization after the leader's prophecy failed.

The failed message of earth's destruction, purportedly sent by aliens to a woman in 1956, became a disconfirmed expectancy that increased dissonance between cognitions, thereby causing most members of the impromptu cult to lessen the dissonance by accepting a new prophecy: that the aliens had instead spared the planet for their sake.

Studies have not so far detected any gender or cross-cultural differences.

Basic Theory

Cognitions which contradict each other are said to be dissonant, while cognitions which agree with each other are said to be consonant. Cognitions which neither agree nor disagree with each other are said to be "irrelevant.

The introduction of a new cognition that is dissonant with a currently held cognition creates a state of "dissonance," the magnitude of which relates to the relative importance of the involved cognitions. Dissonance can be reduced either by eliminating dissonant cognitions, or by adding new consonant cognitions. The maximum possible dissonance is equal to the resistance to change of the less resistant cognition; therefore, once dissonance reaches a level that overcomes the resistance of one of the cognitions involved, that cognition will be changed or eliminated, and dissonance will be reduced.

This leads some peoples who feel dissonance to seek information that will reduce dissonance and avoid information that will increase dissonance. People who are involuntarily exposed to information that increases dissonance are likely to discount that information, either by ignoring it, misinterpreting it, or denying it.