# Affirming the Consequent

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An Affirming the Consequent is an argument pattern that ...

**See:**Abductive Logic, Formal Fallacy, Converse (Logic), Argument Form, Validity, Contraposition, Consequent, Indicative Conditional, Argument Form.

## References

### 2015

- (Wikipedia, 2015) ⇒ http://en.wikipedia.org/wiki/Affirming_the_consequent Retrieved:2015-1-2.
**Affirming the consequent**, sometimes called**converse error**or fallacy of the converse, is a formal fallacy of inferring the converse from the original statement. The corresponding argument has the general form:- If
*P*, then*Q*. *Q*.- Therefore,
*P*.

- If
- An argument of this form is invalid, i.e., the conclusion can be false even when statements 1 and 2 are true. Since
*P*was never asserted as the*only*sufficient condition for*Q*, other factors could account for*Q*(while*P*was false).To put it differently, if

*P*implies*Q*, the**only**inference that can be made is*non-Q*implies*non-P*. (*Non-P*and*non-Q*designate the opposite propositions to*P*and*Q*.) This is known as logical contraposition. Symbolically:[math]\displaystyle{ (P \to Q)\leftrightarrow (\neg Q \to \neg P) }[/math]

The name

*affirming the consequent*derives from the premise*Q*, which affirms the "then" clause of the conditional premise.