"A man without a bias cannot write interesting history - if indeed such a man exists."

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If a person is capable of rectifying his erroneous judgments in the light of new evidence he is not prejudiced. Prejudgments become prejudices only if they are reversible when exposed to new knowledge. A prejudice, unlike a simple misconception, is actively resistant to all evidence that would unseat it. We tend to grow emotional when a prejudice is threatened with contradiction. Thus the difference between ordinary prejudgments and prejudice is that one can discuss and rectify a prejudgment without emotional resistance.

— Gordon Allport