Intuitionism and the modal logic of vagueness

Intuitionistic logic provides an elegant solution to the Sorites Paradox. Its acceptance has been hampered by two factors. First, the lack of an accepted semantics for languages containing vague terms has led even philosophers sympathetic to intuitionism to complain that no explanation has been give...

Täydet tiedot

Bibliografiset tiedot
Päätekijät: Bobzien, S, Rumfitt, I
Aineistotyyppi: Journal article
Julkaistu: Springer Verlag 2020
_version_ 1826283369639444480
author Bobzien, S
Rumfitt, I
author_facet Bobzien, S
Rumfitt, I
author_sort Bobzien, S
collection OXFORD
description Intuitionistic logic provides an elegant solution to the Sorites Paradox. Its acceptance has been hampered by two factors. First, the lack of an accepted semantics for languages containing vague terms has led even philosophers sympathetic to intuitionism to complain that no explanation has been given of why intuitionistic logic is the correct logic for such languages. Second, switching from classical to intuitionistic logic, while it may help with the Sorites, does not appear to offer any advantages when dealing with the so-called paradoxes of higher-order vagueness. We offer a proposal that makes strides on both issues. We argue that the intuitionist’s characteristic rejection of any third alethic value alongside true and false is best elaborated by taking the normal modal system S4M to be the sentential logic of the operator ‘it is clearly the case that’. S4M opens the way to an account of higher-order vagueness which avoids the paradoxes that have been thought to infect the notion. S4M is one of the modal counterparts of the intuitionistic sentential calculus (IPC) and we use this fact to explain why IPC is the correct sentential logic to use when reasoning with vague statements. We also show that our key results go through in an intuitionistic version of S4M. Finally, we deploy our analysis to reply to Timothy Williamson’s objections to intuitionistic treatments of vagueness.
first_indexed 2024-03-07T00:57:53Z
format Journal article
id oxford-uuid:88b730c1-bf96-4766-a842-d3c2834d8f30
institution University of Oxford
last_indexed 2024-03-07T00:57:53Z
publishDate 2020
publisher Springer Verlag
record_format dspace
spelling oxford-uuid:88b730c1-bf96-4766-a842-d3c2834d8f302022-03-26T22:19:18ZIntuitionism and the modal logic of vaguenessJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:88b730c1-bf96-4766-a842-d3c2834d8f30Symplectic Elements at OxfordSpringer Verlag2020Bobzien, SRumfitt, IIntuitionistic logic provides an elegant solution to the Sorites Paradox. Its acceptance has been hampered by two factors. First, the lack of an accepted semantics for languages containing vague terms has led even philosophers sympathetic to intuitionism to complain that no explanation has been given of why intuitionistic logic is the correct logic for such languages. Second, switching from classical to intuitionistic logic, while it may help with the Sorites, does not appear to offer any advantages when dealing with the so-called paradoxes of higher-order vagueness. We offer a proposal that makes strides on both issues. We argue that the intuitionist’s characteristic rejection of any third alethic value alongside true and false is best elaborated by taking the normal modal system S4M to be the sentential logic of the operator ‘it is clearly the case that’. S4M opens the way to an account of higher-order vagueness which avoids the paradoxes that have been thought to infect the notion. S4M is one of the modal counterparts of the intuitionistic sentential calculus (IPC) and we use this fact to explain why IPC is the correct sentential logic to use when reasoning with vague statements. We also show that our key results go through in an intuitionistic version of S4M. Finally, we deploy our analysis to reply to Timothy Williamson’s objections to intuitionistic treatments of vagueness.
spellingShingle Bobzien, S
Rumfitt, I
Intuitionism and the modal logic of vagueness
title Intuitionism and the modal logic of vagueness
title_full Intuitionism and the modal logic of vagueness
title_fullStr Intuitionism and the modal logic of vagueness
title_full_unstemmed Intuitionism and the modal logic of vagueness
title_short Intuitionism and the modal logic of vagueness
title_sort intuitionism and the modal logic of vagueness
work_keys_str_mv AT bobziens intuitionismandthemodallogicofvagueness
AT rumfitti intuitionismandthemodallogicofvagueness