Fallacies Involving Credibility:
The Ad Hominem Fallacy of Tu Quoque

Suppose that someone criticizes you for telling a white lie. If your critic is a notorious liar, you would probably be tempted to say, "Look who's talking!" This response is certainly understandable--no one enjoys being censured by a moral inferior--but it is fallacious. It's a species of ad hominem known as the tu quoque ("you're another") argument. The fact that someone else is guilty of an accusation doesn't prove that you are innocent. A related version of the ad hominem fallacy occurs when we attack someone's position by claiming that it is inconsistent with his or her practice or other positions.

The Ad Hominem Fallacy of Poisoning the Well

Fallacies Involving Credibility

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