{ "id": "1808.10007", "version": "v1", "published": "2018-08-29T18:34:00.000Z", "updated": "2018-08-29T18:34:00.000Z", "title": "Modal Logic With Non-deterministic Semantics: Part I - Propositional Case", "authors": [ "Marcelo E. Coniglio", "Luis FariƱas del Cerro", "Newton M. Peron" ], "categories": [ "math.LO" ], "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.", "revisions": [ { "version": "v1", "updated": "2018-08-29T18:34:00.000Z" } ], "analyses": { "subjects": [ "03B45" ], "keywords": [ "modal logic", "propositional case", "finite deterministic matrices", "completeness", "axiom holds" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }