That every first-order theory has a coherent conservative extension is regarded by some as
obvious, even trivial, and by others as not at all obvious, but instead remarkable and …

An important application of focused variants of Gentzen's sequent calculus proof rules is the
construction of (possibly) large synthetic inference rules. This paper examines the synthetic …

This thesis introduces the" method of structural refinement", which serves as a means of
transforming the relational semantics of a modal and/or constructive logic into …

This paper studies the relationship between labelled and nested calculi for propositional
intuitionistic logic, first-order intuitionistic logic with non-constant domains and first-order …

This paper presents an overview of the methods of hypersequents and display sequents in
the proof theory of non-classical logics. In contrast with existing surveys dedicated to …

As part of a general research programme into the expressive power of different
generalisations of the sequent framework we investigate hypersequent calculi given by rules …

We present some hypersequent calculi for all systems of the classical cube and their
extensions with axioms, and and for every, rule. The calculi are internal as they only employ …

The unified correspondence theory for distributive lattice expansion logics (DLE-logics) is
specialized to strict implication logics. As a consequence of a general semantic consevativity …

In this thesis we consider generic tools and techniques for the proof-theoretic investigation of
not necessarily normal modal logics based on minimal, intuitionistic or classical …

This paper gives a broad account of the various sequent-based proof formalisms in the proof-
theoretic literature. We consider formalisms for various modal and tense logics, intuitionistic …