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UNSOUND INFERENCES MAKE PROOFS SHORTER

Published online by Cambridge University Press:  14 March 2019

JUAN P. AGUILERA
Affiliation:
INSTITUTE OF DISCRETE MATHEMATICS AND GEOMETRY VIENNA UNIVERSITY OF TECHNOLOGY WIEDNER HAUPTSTRAßE 8–10, 1040VIENNA, AUSTRIAE-mail: aguilera@logic.at
MATTHIAS BAAZ
Affiliation:
INSTITUTE OF DISCRETE MATHEMATICS AND GEOMETRY VIENNA UNIVERSITY OF TECHNOLOGY WIEDNER HAUPTSTRAßE 8–10, 1040VIENNA, AUSTRIAE-mail: baaz@logic.at

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 nonelementarily shorter than LK-proofs.

Type
Articles
Copyright
Copyright © The Association for Symbolic Logic 2019 

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References

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