Results about logics that were new with proof systems other than sequent calculus

[Revantha Ramanayake]

Dear colleagues,

Many new results and new insights about classical and non-classical logics have been obtained using the sequent calculus, e.g. Gentzen's consistency argument; interpolation; decidability, complexity; etc.

I would like to identify results and insights *about logics* that were *new*, and that were obtained using proof systems---other than the sequent calculus---that utilised some notion of analyticity / a restriction of proof space such as the subformula property. I am interested across all logics and all sorts of proof systems like hypersequent, nested, labelled, display, proof nets, deep inference based. Here I am viewing a logic as a set of formulas.

I would be pleased to see your thoughts and references ! You could comment on my post at the The Proof Theory Blog (link below), reply here, or write to me directly.

https://prooftheory.blog/2021/08/23/new-results-about-logics-using-proof-systems-other-than-sequent-calculus/

Best wishes,

Revantha Ramanayake
<d.r.s.ramanayake at rug.nl>