Cognitive dissonance is a state that an individual reaches once they have an imbalance between cognitions. For the purpose of this theory, cognitions are defined as being an attitude, emotion, belief or value, or even a mixture of these cognitions.
Once two cognitions are held and there is a conflict of interests between them, the individual falls into a state of cognitive dissonance. This may be demonstrated by an individual purchasing a brand of washing machine, initially believing that it was the best product to buy. Their cognition is that they have a good washing machine. However, after the purchase, they may be exposed to another cognition that informs them that there is a better washing machine out on the market (for example, through an advertisement). This then leads to an imbalance between their cognitions and a psychological state which needs to seek consonance between the two cognitions.
A person in a state of cognitive dissonance will then seek consonance through a variety of behaviours, for example, even deriding the new improved washing machine, and perceiving the new advertisement as untrue. By doing this, they can then allow their cognitions to be in a consonant state once more.
However, there are other ways of reducing the state of dissonance. One example is through selecting information after the purchase. It might be that a person would purposefully avoid other washing machine advertisements knowing that the decision had been made and finding out about other products could lead to some discomfort.
Festinger proposed that Cognitive dissonance is a similar psychological tension to hunger and thirst and that people will seek to resolve this tension.
Some people believe that cognitive dissonance can be instrumental in the creation of conspiracy theories. Suppose that Fred believes that satanic ritual abuse kills hundreds of thousands every year. However, these supposed deaths don't get reported in the media. This leads Fred into cognitive dissonance, which he can resolve either by changing his belief in satanic ritual abuse, or by believing that satanic cultists have infiltrated the media. In the latter case, Fred's original belief is augmented by a new belief in a media conspiracy, and this starts the process towards the creation of a new conspiracy theory.
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