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modus tollens

noun
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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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“Modus tollens.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/modus%20tollens. Accessed 25 Feb. 2021.

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