Two wrongs make a right

In rhetoric and ethics, "two wrongs make a right" and "two wrongs don't make a right" are phrases that denote philosophical norms. "Two wrongs make a right" is a fallacy of relevance, in which an allegation of wrongdoing is countered with a similar allegation. Its antithesis, "two wrongs don't make a right", is a proverb used to rebuke or renounce wrongful conduct as a response to another's transgression.

The phrase "two wrongs infer one right" appears in a poem dated to 1734, published in The London Magazine.

This is an informal fallacy that occurs when that, if one wrong is committed, then another wrong will cancel it out.

The unstated premise is that breaking the law (or the wrong) is justified, as long as the other party also does so. It is often used as a red herring, or an attempt to change or distract from the issue. For example:

Even if President Roberts lied in his Congressional testimony, this does not establish a precedent that makes it acceptable for President Williams to do so as well. (At best, it means Williams is no worse than Roberts.) By invoking the fallacy, the contested issue of lying is ignored.

The tu quoque fallacy is a specific type of "two wrongs make a right". Accusing another of not practicing what they preach, while appropriate in some situations, does not in itself invalidate an action or statement that is perceived as contradictory.

Common use of the term, in the realm of business ethics, has been criticized by scholar Gregory S. Kavka writing in the Journal of Business Ethics. Kavka refers back to philosophical concepts of retribution by Thomas Hobbes. He states that if something supposedly held up as a moral standard or common social rule is violated enough in society, then an individual or group within society can break that standard or rule as well since this keeps them from being unfairly disadvantaged. As well, in specific circumstances violations of social rules can be defensible if done as direct responses to other violations. For example, Kavka states that it is wrong to deprive someone of their property but it is right to take property back from a criminal who takes another's property in the first place. He also states that one should be careful not to use this ambiguity as an excuse recklessly to violate ethical rules.

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