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Difference between revisions of "Contraposition, law of"

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The logical principle according to which if one statement implies another, then the negation of the latter implies the negation of the former:
 
The logical principle according to which if one statement implies another, then the negation of the latter implies the negation of the former:
  
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$$(A\supset B)\supset(\neg B\supset\neg A).$$
  
 
The law of contraposition is used both in classical and constructive logic.
 
The law of contraposition is used both in classical and constructive logic.

Latest revision as of 13:49, 29 April 2014

The logical principle according to which if one statement implies another, then the negation of the latter implies the negation of the former:

$$(A\supset B)\supset(\neg B\supset\neg A).$$

The law of contraposition is used both in classical and constructive logic.

How to Cite This Entry:
Contraposition, law of. Encyclopedia of Mathematics. URL: http://encyclopediaofmath.org/index.php?title=Contraposition,_law_of&oldid=17630
This article was adapted from an original article by S.K. Sobolev (originator), which appeared in Encyclopedia of Mathematics - ISBN 1402006098. See original article