A Proof-Theoretic Interpolation Theorem for Inquisitive Propositional Logic
A Proof-Theoretic Interpolation Theorem for Inquisitive Propositional Logic
Author(s): Andreas FjellstadSubject(s): Economy
Published by: Wydawnictwo Uniwersytetu Łódzkiego
Keywords: Inquisitive Logic; Harrop formulas; interpolation; Maehara's lemma; intermediate logics
Summary/Abstract: This paper presents a sequent calculus for Inquisitive Propositional Logic obtained by expanding the sequent calculus g3ip for intuitionistic propositional logic with suitable rules for double negation elimination for atoms and the Split Property. A suitable rule for the Split Property is obtained by taking advantage of the connection between the truth-conditional fragment in Inquisitive Logic and Harrop formulas. The paper proves admissibility of cut for the sequent calculus and uses the sequent calculus to prove interpolation for Inquisitive Propositional Logic. Interpolation is obtained using Maehara’s lemma
Journal: Bulletin of the Section of Logic
- Issue Year: 55/2026
- Issue No: 1
- Page Range: 49-71
- Page Count: 23
- Language: English
