English

On the strongest three-valued paraconsistent logic contained in classical logic and its dual

Logic in Computer Science 2021-03-08 v7 Logic

Abstract

LP,F^{\supset,\mathsf{F}} is a three-valued paraconsistent propositional logic which is essentially the same as J3. It has most properties that have been proposed as desirable properties of a reasonable paraconsistent propositional logic. However, it follows easily from already published results that there are exactly 8192 different three-valued paraconsistent propositional logics that have the properties concerned. In this paper, properties concerning the logical equivalence relation of a logic are used to distinguish LP,F^{\supset,\mathsf{F}} from the others. As one of the bonuses of focussing on the logical equivalence relation, it is found that only 32 of the 8192 logics have a logical equivalence relation that satisfies the identity, annihilation, idempotent, and commutative laws for conjunction and disjunction. For most properties of LP,F^{\supset,\mathsf{F}} that have been proposed as desirable properties of a reasonable paraconsistent propositional logic, its paracomplete analogue has a comparable property. In this paper, properties concerning the logical equivalence relation of a logic are also used to distinguish the paracomplete analogue of LP,F^{\supset,\mathsf{F}} from the other three-valued paracomplete propositional logics with those comparable properties.

Keywords

Cite

@article{arxiv.1702.03414,
  title  = {On the strongest three-valued paraconsistent logic contained in classical logic and its dual},
  author = {C. A. Middelburg},
  journal= {arXiv preprint arXiv:1702.03414},
  year   = {2021}
}

Comments

17 pages, version that is accepted for publication, there is some text overlap between this paper and arXiv:1508.06899 [cs.LO]

R2 v1 2026-06-22T18:15:36.683Z