The Anatomy of a Great Deception

Per http://en.wikipedia.org/wiki/Cognitive_dissonance:

In psychology, cognitive dissonance is the mental stress or discomfort experienced by an individual who holds two or more contradictory beliefs, ideas, or values at the same time, or is confronted by new information that conflicts with existing beliefs, ideas, or values.

Leon Festinger's theory of cognitive dissonance focuses on how humans strive for internal consistency. When inconsistency (dissonance) is experienced, individuals tend to become psychologically uncomfortable and are motivated to attempt to reduce this dissonance, as well as actively avoiding situations and information which are likely to increase it.