Difference between revisions of "Logical law"
From Encyclopedia of Mathematics
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| − | A [[Logical formula|logical formula]] that becomes a true proposition under any interpretation of the variables for propositions and predicates that occur in it. Such formulas are called generally valid, universally valid or tautologies. For example, the tautology | + | A [[Logical formula|logical formula]] that becomes a true proposition under any interpretation of the variables for propositions and predicates that occur in it. Such formulas are called generally valid, universally valid or tautologies. For example, the tautology $A\lor\neg A$ expresses the [[Law of the excluded middle|law of the excluded middle]]. |
Latest revision as of 13:21, 9 April 2014
in mathematical logic
A logical formula that becomes a true proposition under any interpretation of the variables for propositions and predicates that occur in it. Such formulas are called generally valid, universally valid or tautologies. For example, the tautology $A\lor\neg A$ expresses the law of the excluded middle.
Comments
References
| [a1] | A. Grzegorczyk, "An outline of mathematical logic" , Reidel (1974) |
How to Cite This Entry:
Logical law. Encyclopedia of Mathematics. URL: http://encyclopediaofmath.org/index.php?title=Logical_law&oldid=18440
Logical law. Encyclopedia of Mathematics. URL: http://encyclopediaofmath.org/index.php?title=Logical_law&oldid=18440
This article was adapted from an original article by V.E. Plisko (originator), which appeared in Encyclopedia of Mathematics - ISBN 1402006098. See original article