# Denying the Antecedent

Like affirming the consequent is a logical fallacy in the form of modus ponens, denying the antecedent is a fallacy in the form of modus tollens. Recall that modus tollens uses the premises

P = > Q
~Q

to conclude ~P.

Denying the antecedent uses the premises

P => Q
~P

to conclude ~P. However, this is not a valid argument; P may or may not be true based on the information presented.

Denying the antecedent gets its name because one of the premises denies (negates) the antecedent of the implication.

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