The coinductive formulation of common knowledge

We study the coinductive formulation of common knowledge in type theory. We formalise both the traditional relational semantics and an operator semantics, similar in form to the epistemic system S5, but at the level of events on possible worlds rather than as a logical derivation system. We have two...

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Main Authors: Baston, Colm, Capretta, Venanzio
Format: Conference or Workshop Item
Language:English
Published: 2018
Online Access:https://eprints.nottingham.ac.uk/53576/
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author Baston, Colm
Capretta, Venanzio
author_facet Baston, Colm
Capretta, Venanzio
author_sort Baston, Colm
building Nottingham Research Data Repository
collection Online Access
description We study the coinductive formulation of common knowledge in type theory. We formalise both the traditional relational semantics and an operator semantics, similar in form to the epistemic system S5, but at the level of events on possible worlds rather than as a logical derivation system. We have two major new results. Firstly, the operator semantics is equivalent to the relational semantics: we discovered that this requires a new hypothesis of semantic entailment on operators, not known in previous literature. Secondly, the coinductive version of common knowledge is equivalent to the traditional transitive closure on the relational interpretation. All results are formalised in the proof assistants Agda and Coq.
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format Conference or Workshop Item
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institution University of Nottingham Malaysia Campus
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language English
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publishDate 2018
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spelling nottingham-535762018-08-31T10:13:23Z https://eprints.nottingham.ac.uk/53576/ The coinductive formulation of common knowledge Baston, Colm Capretta, Venanzio We study the coinductive formulation of common knowledge in type theory. We formalise both the traditional relational semantics and an operator semantics, similar in form to the epistemic system S5, but at the level of events on possible worlds rather than as a logical derivation system. We have two major new results. Firstly, the operator semantics is equivalent to the relational semantics: we discovered that this requires a new hypothesis of semantic entailment on operators, not known in previous literature. Secondly, the coinductive version of common knowledge is equivalent to the traditional transitive closure on the relational interpretation. All results are formalised in the proof assistants Agda and Coq. 2018-07-04 Conference or Workshop Item PeerReviewed application/pdf en https://eprints.nottingham.ac.uk/53576/1/common_knowledge.pdf Baston, Colm and Capretta, Venanzio (2018) The coinductive formulation of common knowledge. In: ITP 2018 - Interactive Theorem Proving, 9-12 August 2018, Oxford, UK. https://link.springer.com/chapter/10.1007%2F978-3-319-94821-8_8 10.1007/978-3-319-94821-8_8 10.1007/978-3-319-94821-8_8 10.1007/978-3-319-94821-8_8
spellingShingle Baston, Colm
Capretta, Venanzio
The coinductive formulation of common knowledge
title The coinductive formulation of common knowledge
title_full The coinductive formulation of common knowledge
title_fullStr The coinductive formulation of common knowledge
title_full_unstemmed The coinductive formulation of common knowledge
title_short The coinductive formulation of common knowledge
title_sort coinductive formulation of common knowledge
url https://eprints.nottingham.ac.uk/53576/
https://eprints.nottingham.ac.uk/53576/
https://eprints.nottingham.ac.uk/53576/