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Dealing With Logical Omniscience: Expressiveness and Pragmatics

Joseph Y. Halpern·Riccardo Pucella
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Abstract

We examine four approaches for dealing with the logical omniscience problem and their potential applicability: the syntactic approach, awareness, algorithmic knowledge, and impossible possible worlds. Although in some settings these approaches are equi-expressive and can capture all epistemic states, in other settings of interest (especially with probability in the picture), we show that they are not equi-expressive. We then consider the pragmatics of dealing with logical omniscience-- how to choose an approach and construct an appropriate model.

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Joseph Y. Halpern, Riccardo Pucella. 2007-02-01. Dealing With Logical Omniscience: Expressiveness and Pragmatics. https://arxiv.org/abs/cs/0702011

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