Modal Logic With Non-deterministic Semantics: Part I - Propositional Case
Logic
2018-08-31 v1
Abstract
In 1988, Ivlev proposed four-valued non-deterministic semantics for modal logics in which the alethic T axiom holds good. Unfortunately, no completeness was proved. In previous work, we proved completeness for some Ivlev systems and extended his hierarchy, proposing weaker six-valued systems in which the T axiom was replaced by the deontic D axiom. Here, we eliminate both axioms, proposing even weaker systems with eight values. Besides, we prove completeness for those new systems. It is natural to ask if a characterization by finite ordinary (deterministic) logical matrices would be possible for all those systems. We will show that finite deterministic matrices do not characterize any of them.
Keywords
Cite
@article{arxiv.1808.10007,
title = {Modal Logic With Non-deterministic Semantics: Part I - Propositional Case},
author = {Marcelo E. Coniglio and Luis Fariñas del Cerro and Newton M. Peron},
journal= {arXiv preprint arXiv:1808.10007},
year = {2018}
}