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fallacy

A common pattern of bad reasoning.

A fallacy is a recurring kind of mistake in reasoning: an argument that seems to support its conclusion but does not. A formal fallacy is a mistake in the argument's form; later chapters add informal fallacies, which are mistakes of relevance, evidence, or language.

Examples

  • Affirming the consequent is a fallacy that imitates modus ponens.

See also

formal fallacy affirming the consequent
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