English

Reasoning Around Paradox with Grounded Deduction

Logic 2025-04-07 v4 Logic in Computer Science

Abstract

How can we reason around logical paradoxes without falling into them? This paper introduces grounded deduction or GD, a Kripke-inspired approach to first-order logic and arithmetic that is neither classical nor intuitionistic, but nevertheless appears both pragmatically usable and intuitively justifiable. GD permits the direct expression of unrestricted recursive definitions -- including paradoxical ones such as 'L := not L' -- while adding dynamic typing premises to certain inference rules so that such paradoxes do not lead to inconsistency. This paper constitutes a preliminary development and investigation of grounded deduction, to be extended with further elaboration and deeper analysis of its intriguing properties.

Keywords

Cite

@article{arxiv.2409.08243,
  title  = {Reasoning Around Paradox with Grounded Deduction},
  author = {Bryan Ford},
  journal= {arXiv preprint arXiv:2409.08243},
  year   = {2025}
}
R2 v1 2026-06-28T18:42:49.395Z