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logic

Denying the antecedent

taught

If P then Q; not P; so not Q. Invalid: it imitates modus tollens.

Taught in

Affirming the consequent and denying the antecedent
Introduction to Logic

Requires

modus-tollens-form required

Required by

Telling the valid conditional forms from their look-alikes required

Local knowledge map

Local knowledge map

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Solid arrows are required prerequisites; dashed are recommended or helpful. Lower rows are more foundational. Click any box to jump to that concept.