Sequent Calculi with procedure calls

Mahfuza Farooque 1, 2 Stéphane Graham-Lengrand 1, 2
2 PARSIFAL - Proof search and reasoning with logic specifications
LIX - Laboratoire d'informatique de l'École polytechnique [Palaiseau], Inria Saclay - Ile de France
Abstract : In this paper, we introduce two focussed sequent calculi, LKp(T) and LK+(T), that are based on Miller-Liang's LKF system for polarised classical logic. The novelty is that those sequent calculi integrate the possibility to call a decision procedure for some background theory T, and the possibility to polarise literals "on the fly" during proof-search. These features are used in our other works to simulate the DPLL(T) procedure as proof-search in the extension of LKp(T) with a cut-rule. In this report we therefore prove cut-elimination in LKp(T). Contrary to what happens in the empty theory, the polarity of literals affects the provability of formulae in presence of a theory T. On the other hand, changing the polarities of connectives does not change the provability of formulae, only the shape of proofs. In order to prove this, we introduce a second sequent calculus, LK+(T) that extends LKp(T) with a relaxed focussing discipline, but we then show an encoding of LK+(T) back into the more restrictive system LK(T). We then prove completeness of LKp(T) (and therefore of LK+(T)) with respect to first-order reasoning modulo the ground propositional lemmas of the background theory T .
Document type :
Complete list of metadatas

Cited literature [4 references]  Display  Hide  Download
Contributor : Stéphane Graham-Lengrand <>
Submitted on : Tuesday, September 17, 2013 - 11:46:06 AM
Last modification on : Wednesday, March 27, 2019 - 4:41:29 PM
Long-term archiving on : Thursday, April 6, 2017 - 9:13:23 PM


Files produced by the author(s)


  • HAL Id : hal-00779199, version 4
  • ARXIV : 1304.6279



Mahfuza Farooque, Stéphane Graham-Lengrand. Sequent Calculi with procedure calls. 2013. ⟨hal-00779199v4⟩



Record views


Files downloads