Articles
Published 13-01-2025
Keywords
- Arthur Prior,
- System Q,
- tableau systems
How to Cite
Bräuner, T. (2025). Analytic Proof-Theory for Prior’s System Q: First Steps. Logic and Philosophy of Time, 6(1). https://doi.org/10.54337/lpt.v6i1.9937
Copyright (c) 2025 Logic and Philosophy of Time

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.
Abstract
Arthur Prior introduced the three-valued modal logic called the Q system. A few axiom systems for the Q system can be found in the literature, but no analytic proof-theory in the form of tableau-, sequent- or natural deduction systems. In the present paper we demonstrate how to turn a formal semantics for the Q system into a tableau system, whereby we provide a proof system that is suitable for actual reasoning.
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