Interpolation in Classical Propositional Logic

Patrick Koopmann; Christoph Wernhard; Frank Wolter

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arXiv · 2508.11449

Interpolation in Classical Propositional Logic

Patrick Koopmann·Christoph Wernhard·Frank Wolter

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Abstract

We introduce Craig interpolation and related notions such as uniform interpolation, Beth definability, and theory decomposition in classical propositional logic. We present four approaches to computing interpolants: via quantifier elimination, from formulas in disjunctive normal form, and by extraction from resolution or tableau refutations. We close with a discussion of the size of interpolants and links to circuit complexity.

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Patrick Koopmann, Christoph Wernhard, Frank Wolter. 2025-08-15. Interpolation in Classical Propositional Logic. https://arxiv.org/abs/2508.11449

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