affirming the consequent

logic

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July 17, 2026

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The "affirmation of the consequent" is a logical fallacy. It occurs when one incorrectly infers the truth of an antecedent (the "if" part of a statement) from the truth of the consequent (the "then" part).

For example, consider the statement: "If it rains, then the game is canceled."
The fallacy would be to observe that the game is canceled and then conclude that it must have rained. However, the game could have been canceled for other reasons.

This logical error is also known as the "fallacy of the consequent" or "assertion of the consequent".123

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Deduction
In one such fallacy, “affirming the consequent,” the categorical proposition affirms the consequent of the conditional, and the conclusion affirms the antecedent, as in the example:
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In one such fallacy, “affirming the consequent,” the categorical proposition affirms the consequent of the conditional, and the conclusion affirms the antecedent, as in the example:
Read More