English

On three-valued presentations of classical logic

Logic 2024-11-20 v1

Abstract

Given a three-valued definition of validity, which choice of three-valued truth tables for the connectives can ensure that the resulting logic coincides exactly with classical logic? We give an answer to this question for the five monotonic consequence relations stst, ssss, tttt, ssttss\cap tt, and tsts, when the connectives are negation, conjunction, and disjunction. For tsts and ssttss\cap tt the answer is trivial (no scheme works), and for ssss and tttt it is straightforward (they are the collapsible schemes, in which the middle value acts like one of the classical values). For stst, the schemes in question are the Boolean normal schemes that are either monotonic or collapsible.

Cite

@article{arxiv.2312.16035,
  title  = {On three-valued presentations of classical logic},
  author = {Bruno da Ré and Damian Szmuc and Emmanuel Chemla and Paul Égré},
  journal= {arXiv preprint arXiv:2312.16035},
  year   = {2024}
}

Comments

Review of Symbolic Logic

R2 v1 2026-06-28T14:02:07.401Z