modus tollens

noun

modus tol·​lens

-ˈtäˌlenz

plural modi tollentes

-(ˌ)täˈlen‧ˌtēz

: a mode of reasoning from a hypothetical proposition according to which if the consequent be denied the antecedent is denied (as, if A is true, B is true; but B is false; therefore A is false)

Word History

Etymology

New Latin, removing mode

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