Cognitive dissonance is the term used to describe the mental discomfort experienced by an individual when his attitudes, beliefs or behaviours are contradicted in the face of new information. This concept was developed by the American psychologist Leon Festinger in the 1950s. When confronted by facts that contradict their beliefs and attitudes, people try to find a way to resolve the contradiction to lessen their discomfort. In ‘A Theory of Cognitive Dissonance’ (1957), Festinger proposed that individuals experience an inner drive to hold all their attitudes and beliefs in harmony and avoid disharmony. This is known as the principle of cognitive consistency.

Cognitive dissonance can be seen as an antecedent condition which leads to activity oriented toward dissonance reduction just as hunger leads toward activity oriented toward hunger reduction. It is a very different motivation from what psychologists are used to dealing with but, as we shall see, nonetheless powerful. ~Leon Festinger

Cognitive dissonance can occur in various areas of life, but it is all the more evident in situations where a person’s actions clash with the beliefs that are fundamental to his self-identity. The degree of dissonance experienced varies from person to person and on factors such as:

  1. Cognitions that are significant and personally meaningful tend to cause greater dissonance.

  2. The ratio between dissonant and consonant thoughts influences the strength of dissonance.

The greater the strength of the dissonance, the greater is the need to reduce the feelings of mental stress.

A person experiencing internal inconsistency goes through psychological stress and is motivated to reduce the cognitive dissonance in the following ways:

  1. Change the behaviour or the cognition

  2. Justify the behaviour or the cognition by changing the conflicting cognition

  3. Justify the behaviour or the cognition by adding new cognitions

  4. Ignore or deny the information that contradicts with the existing belief or action

The theory can be understood clearly by taking the example of a cigarette smoker. The individual knows that smoking is harmful for his health. However, he enjoys smoking and feels that it helps him deal with stress and anxiety. Thus, he is experiencing cognitive dissonance and can reduce his mental distress by following any one of the four options. Firstly, he quits smoking. Secondly, he tells himself that smoking isn't as bad as everyone says. Thirdly, he says that since he exercises on a daily basis, he is quite healthy and smoking won't harm him. Fourthly, he declares that studies on the ill effects of smoking on health are inconclusive.

Although a great deal of research has been done on the phenomenon of cognitive dissonance, the theory suffers from the portrayal of the use of irrational methods to establish harmony between attitude and behaviour. Moreover, there is no way to objectively measure cognitive dissonance, thereby making the experience a subjective one. Finally, a number of studies supporting the theory of cognitive dissonance suffer from sampling bias and low ecological validity.