Unsound Inferences Make Proofs Shorter

Abstract

We give examples of calculi that extend Gentzen's sequent calculus LK by unsound quantifier inferences in such a way that (i) derivations lead only to true sequents, and (ii) proofs therein are non-elementarily shorter than LK-proofs.

arXiv comment21 pages. July 2017 preprint

References in corpus (1)

• The Epsilon Calculus and Herbrand Complexity

Cited by in corpus (1)

• Efficient elimination of Skolem functions in ${\text{LK}}^{\text{h}}$