Proof Theory for Indexed Nested Sequents
نویسندگان
چکیده
Fitting’s indexed nested sequents can be used to give deductive systems to modal logics which cannot be captured by pure nested sequents. In this paper we show how the standard cut-elimination procedure for nested sequents can be extended to indexed nested sequents, and we discuss how indexed nested sequents can be used for intuitionistic modal logics.
منابع مشابه
Inducing Syntactic Cut-Elimination for Indexed Nested Sequents
The key to the proof-theoretical study of a logic is a cutfree proof calculus. Unfortunately there are many logics of interest lacking suitable proof calculi. The proof formalism of nested sequents was recently generalised to indexed nested sequents in order to yield cutfree proof calculi for extensions of the modal logic K by Geach (LemmonScott) axioms. The proofs of completeness and cut-elimi...
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