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arXiv · 2610.40800

On Some Logics Intermediate Between S4.2 and S4.3 Defined by the Notion of Independence

Maciej A. Hałapacz
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Abstract

Hamkins and Loewe described modal logic S4.2 through the notion of sets of independent buttons - statements that are possibly necessary - and switches - necessarily contingent statements. In this article we investigate logics intermediate between S4.2 and S4.3 that are defined through a different notion of independence. We provide an axiomatic description of such logics, state some basic facts and prove various completeness and decidability results.

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Maciej A. Hałapacz. 2026-10-29. On Some Logics Intermediate Between S4.2 and S4.3 Defined by the Notion of Independence. https://doi.org/10.4204/eptcs.455.2

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