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modus tol·lens | \ -ˈtäˌlenz \
plural modi tollentes\ -(ˌ)täˈlen‧ˌtēz \
Definition of modus tollens
: 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)
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Merriam-Webster unabridgedWords at Play
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