http://glottopedia.org/index.php?action=history&feed=atom&title=Modal_logicModal logic - Revision history2026-05-03T19:32:07ZRevision history for this page on the wikiMediaWiki 1.34.2http://glottopedia.org/index.php?title=Modal_logic&diff=7980&oldid=prevWohlgemuth: utrecht2009-02-17T18:36:36Z<p>utrecht</p>
<p><b>New page</b></p><div>'''Modal logic''' is the logic of sentences with modal expressions like ''necessarily'' and ''possibly''. These expressions can be added as operators (say N and P) to standard logic:<br />
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(i) If phi is a formula, then Nphi is a formula<br />
(ii) If phi is a formula, then Pphi is a formula<br />
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Sentences like these are interpreted in terms of possible worlds. Nphi is true if phi is true in every possible world; Pphi is true if phi is true in some possible world.<br />
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=== Links ===<br />
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[http://www2.let.uu.nl/UiL-OTS/Lexicon/zoek.pl?lemma=Modal+logic&lemmacode=549 Utrecht Lexicon of Linguistics]<br />
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=== References ===<br />
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* Gamut, L.T.F. 1991. ''Logic, language, and meaning,'' Univ. of Chicago Press, Chicago.<br />
* Hughes, G.E. and M.J. Cresswell 1968. ''An Introduction to Modal Logic,'' Methuen:London.<br />
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[[Category:Semantics]]</div>Wohlgemuth