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The Fitch-Church Paradox and First Order Modal Logic

Proietti, Carlo LU (2016) In Erkenntnis 81(1). p.87-104
Abstract
Reformulation strategies for solving Fitch’s paradox of knowability date back to Edgington. Their core assumption is that the formula \ , from which the paradox originates, does not correctly express the intended meaning of the verification thesis , which should concern possible knowledge of actual truths, and therefore the contradiction does not represent a logical refutation of verificationism. Supporters of these solutions claim that can be reformulated in a way that blocks the derivation of the paradox. Unfortunately, these reformulation proposals come with other problems, on both the logical and the philosophical side. We claim that in order to make the reformulation idea consistent and adequate one should analyze the paradox from the... (More)
Reformulation strategies for solving Fitch’s paradox of knowability date back to Edgington. Their core assumption is that the formula \ , from which the paradox originates, does not correctly express the intended meaning of the verification thesis , which should concern possible knowledge of actual truths, and therefore the contradiction does not represent a logical refutation of verificationism. Supporters of these solutions claim that can be reformulated in a way that blocks the derivation of the paradox. Unfortunately, these reformulation proposals come with other problems, on both the logical and the philosophical side. We claim that in order to make the reformulation idea consistent and adequate one should analyze the paradox from the point of view of a quantified modal language. An approach in this line was proposed by, among others, Kvanvig but was not fully developed in its technical details. Here we approach the paradox by means of a first order hybrid modal logic , a tool that strikes us as more adequate to express transworld reference and the rigidification needed to consistently express this idea. The outcome of our analysis is ambivalent. Given a first order formula we are able to express the fact that it is knowable in a way which is both consistent and adequate. However, one must give up the possibility of formulating as a substitution free schema of the kind \ . We propose that one may instead formulate by means of a recursive translation of the initial formula, being aware that many alternative translations are possible. (Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
Erkenntnis
volume
81
issue
1
pages
87 - 104
publisher
Springer
external identifiers
  • scopus:84955754013
  • wos:000374168600006
ISSN
1572-8420
DOI
10.1007/s10670-015-9730-5
language
English
LU publication?
yes
additional info
Published online ahead of print 09 Apr 2015
id
5642477f-934b-41d9-b02d-6ae359647a1b (old id 5275266)
date added to LUP
2016-04-01 10:37:40
date last changed
2022-02-17 19:48:15
@article{5642477f-934b-41d9-b02d-6ae359647a1b,
  abstract     = {{Reformulation strategies for solving Fitch’s paradox of knowability date back to Edgington. Their core assumption is that the formula \ , from which the paradox originates, does not correctly express the intended meaning of the verification thesis , which should concern possible knowledge of actual truths, and therefore the contradiction does not represent a logical refutation of verificationism. Supporters of these solutions claim that can be reformulated in a way that blocks the derivation of the paradox. Unfortunately, these reformulation proposals come with other problems, on both the logical and the philosophical side. We claim that in order to make the reformulation idea consistent and adequate one should analyze the paradox from the point of view of a quantified modal language. An approach in this line was proposed by, among others, Kvanvig but was not fully developed in its technical details. Here we approach the paradox by means of a first order hybrid modal logic , a tool that strikes us as more adequate to express transworld reference and the rigidification needed to consistently express this idea. The outcome of our analysis is ambivalent. Given a first order formula we are able to express the fact that it is knowable in a way which is both consistent and adequate. However, one must give up the possibility of formulating as a substitution free schema of the kind \ . We propose that one may instead formulate by means of a recursive translation of the initial formula, being aware that many alternative translations are possible.}},
  author       = {{Proietti, Carlo}},
  issn         = {{1572-8420}},
  language     = {{eng}},
  month        = {{02}},
  number       = {{1}},
  pages        = {{87--104}},
  publisher    = {{Springer}},
  series       = {{Erkenntnis}},
  title        = {{The Fitch-Church Paradox and First Order Modal Logic}},
  url          = {{http://dx.doi.org/10.1007/s10670-015-9730-5}},
  doi          = {{10.1007/s10670-015-9730-5}},
  volume       = {{81}},
  year         = {{2016}},
}