What is Modus tollens?
'''Modus tollendo tollens''' ([[Latin]]: ''the way that denies by denying'')<ref>{{cite book | last=Stone | first=Jon R. | year=1996 | title=Latin for the Illiterati: exorcizing the ghosts of a dead language | url=https://archive.org/details/latinforillitera0000ston | publisher=London, UK: Routledge: 60.}}</ref> is a [[valid]], simple [[argument form]] in [[classical logic]]. It is referred to as '''denying the consequent'''. It is closely related to another valid form of argument, ''[[modus ponens]]'' or affirming the antecedent. ''Modus tollens'' is a very common [[rule of inference]], and takes this form: :If ''P'', then ''Q''. :Not ''Q''. :Therefore, not ''P''.<ref>University of North Carolina, Philosophy Department, [http://www.philosophy.uncc.edu/mleldrid/Logic/logiglos.html#modustollens Logic Glossary] {{Webarchive|url=https://web.archive.org/web/20070830160855/http://www.philosophy.uncc.edu/mleldrid/Logic/logiglos.html#modustollens |date=2007-08-30 }}.</ref> ==References== <references/> [[Category:Rules of inference]]