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arXiv · 1711.04634

A Cut-free sequent calculus for modal logic S5

Mojtaba Aghaei·Hamzeh Mohammadi
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Abstract

We present the system G3S5, a Gentzen-style sequent calculus system for the modal propositional logic S5, which in a sense has the subformula property. We formulate the rules of G3 S5 in the system G3S5; which has the subformula property and prove the admissibility of the weakening, contraction and cut rules for it.

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Mojtaba Aghaei, Hamzeh Mohammadi. 2018-05-23. A Cut-free sequent calculus for modal logic S5. https://arxiv.org/abs/1711.04634

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