Cognitive dissonance, an important concept in social psychology (Festinger, 1957), refers to the uncomfortable tension that can exist between two simultaneous and conflicting ideas or feelings—often as a person realizes that s/he has engaged in a behavior inconsistent with the type of person s/he would like to be, or be seen publicly to be. According to the theory, people are motivated to reduce this tension by changing their attitudes, beliefs, or actions. For example, smokers may rationalize their behavior by holding ‘self-exempting beliefs’, such as “The medical evidence that smoking causes cancer is not convincing” or “Many people who smoke all their lives live to a ripe old age, so smoking is not all that bad for you” (Chapman et al., 1993).

Arousing dissonance can be used to achieve behavioral change; one study (Dickerson et al., 1992), for instance, made people mindful of their wasteful water consumption and then made them urge others (publicly commit) to take shorter showers. Subjects in this ‘hypocrisy condition’ subsequently took significantly shorter showers than those who were only reminded that they had wasted water or merely made the public commitment.


Chapman, S., Wong, W. L., & Smith, W. (1993). Self-exempting beliefs about smoking and health: Differences between smokers and ex-smokers. American Journal of Public Health, 83(2), 215-219.

Dickerson, C. A., Thibodeau, R., Aronson, E., & Miller, D. (1992). Using cognitive dissonance to encourage water conservation. Journal of Applied Social Psychology, 22(11), 841-854.

Festinger, L. (1957). A theory of cognitive dissonance. Stanford: Stanford University Press.