contrapositive


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Related to contrapositive: Proof by contradiction, Proof by contrapositive

con·tra·pos·i·tive

 (kŏn′trə-pŏz′ĭ-tĭv)
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.

contrapositive

(ˌkɒntrəˈpɒzɪtɪv)
adj
(Logic) placed opposite or against
n
(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

con•tra•pos•i•tive

(ˌkɒn trəˈpɒz ɪ tɪv)
Logic. adj.
1. of or pertaining to contraposition.
n.
2. a contrapositive statement.
[1855–60]
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contrapositive

noun
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.