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Related to contrapositive: Proof by contradiction, Proof by contrapositive


n. Logic
A proposition derived by negating and permuting the terms of another, equivalent proposition; for example, All not-Y is not-X is the contrapositive of All X is Y.


(Logic) placed opposite or against
(Logic) logic
a. a conditional statement derived from another by negating and interchanging antecedent and consequent
b. a categorial proposition obtained from another, esp validly, by any of a number of operations including negation, transferring the terms, changing their quality, and also possibly weakening from universal to particular


(ˌkɒn trəˈpɒz ɪ tɪv)
Logic. adj.
1. of or pertaining to contraposition.
2. a contrapositive statement.
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Logic. That which is diametrically opposed to another:
References in periodicals archive ?
95--This book gets its name as a contrapositive to the political liberalism of John Rawls and his followers.
5) The contrapositive of "If A, then B" is "If not-B, then not-A.
203) Therefore, by contrapositive, the Double Jeopardy Clause does not apply to a non-criminal proceeding following an acquittal at a criminal proceeding.