Cognitive Dissonance
Cognitive dissonance describes the mental discomfort that results from holding two conflicting beliefs, values, or attitudes. People tend to seek consistency in their attitudes and perceptions, so this conflict causes feelings of unease or discomfort.
This inconsistency between what people believe and how they behave motivates people to engage in actions that will help minimize feelings of discomfort.
Dissonance can be reduced in different ways: changing existing beliefs, rejecting, explaining away, or avoiding new information, adding new beliefs, or reducing the importance of the beliefs.
Causes
There are a number of different situations which can create conflicts that are likely to lead to cognitive dissonance: