π€ AI Summary
How can self-referential paradoxes (e.g., βL := Β¬Lβ) be handled safely without inducing logical inconsistency? This paper introduces Grounded Deduction (GD), a novel non-classical, non-intuitionistic first-order logical and arithmetical framework inspired by Kripkean semantics. GD employs dynamically typed natural deduction rules and a semantic anchoring mechanism to directly model and express unrestricted recursive definitions, while rigorously distinguishing between *definability* and *assertibility*βthereby permitting the formulation of paradoxical statements without inferential collapse. Its key contributions are: (i) the first formal system enabling locally consistent reasoning about self-referential definitions; (ii) verification of GDβs practical usability and intuitive soundness within standard arithmetic; and (iii) a new foundational framework for formalizing self-reference and paradox-laden reasoning that balances expressive power with logical reliability.
π 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.