law of the excluded middle


Also found in: Dictionary, Thesaurus, Medical, Legal.

law of the excluded middle

[¦lȯ əvthē ik‚sklüd·əd ′mid·əl]
(mathematics)
A principle of logic whereby a proposition is either true or false but cannot be both true and false. Also known as principle of dichotomy.
References in periodicals archive ?
Pierce noted that Actuals and Probables DO obey the law of the Excluded Middle, but Possibles do not.
He refined his claims in the final journal article presenting it, narrowing his sights on an "apparently reasonable" version of fuzzy logic, and making explicit the specific instance of the law of the excluded middle on which his proof depended.
If this is so, the law of the excluded middle, which incorporates this 'is,' has sent us off on the wrong track.