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arXiv · 2001.00662

Cut elimination and normalization for generalized single and multi-conclusion sequent and natural deduction calculi

Richard Zach
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Abstract

Any set of truth-functional connectives has sequent calculus rules that can be generated systematically from the truth tables of the connectives. Such a sequent calculus gives rise to a multi-conclusion natural deduction system and to a version of Parigot's free deduction. The elimination rules are "general," but can be systematically simplified. Cut-elimination and normalization hold. Restriction to a single formula in the succedent yields intuitionistic versions of these systems. The rules also yield generalized lambda calculi providing proof terms for natural deduction proofs as in the Curry-Howard isomorphism. Addition of an indirect proof rule yields classical single-conclusion versions of these systems. Gentzen's standard systems arise as special cases.

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BibTeXRIS

Richard Zach. 2021-05-31. Cut elimination and normalization for generalized single and multi-conclusion sequent and natural deduction calculi. https://doi.org/10.1017/s1755020320000015

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