Mistakes Were Made by Carol Tarvis and Elliot Aronson. It's a long discussion on the mechanics of cognitive dissonance and self-justification.
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"A man travels many miles to consult the wisest guru in the land. When he arrives, he asks the great man:
'O wise guru, what is the secret of a happy life?'
'Good judgement,' says the guru.
'But, O wise guru' says the man, 'how do I achieve good judgement'
'Bad judgement,' says the guru"