Truth-values as labels: a general recipe for labelled deduction

• Published in: Journal of applied non-classical logics 2003-01, Vol.13 (3-4), p.277-315
• Main Authors: Sernadas, Cristina, Viganò, Luca, Rasga, João, Sernadas, Amílcar
• Format: Article
• Language: English
• Subjects: labelled deduction; multiple-valued logics; non-classical logics
• ISSN: 1166-3081; 1958-5780
• DOI: 10.3166/jancl.13.277-315

We introduce a general recipe for presenting non-classical logics in a modular and uniform way as labelled deduction systems. Our recipe is based on a labelling mechanism where labels are general entities that are present, in one way or another, in all logics, namely truth-values. More specifically, the main idea underlying our approach is the use of algebras of truth-values, whose operators reflect the semantics we have in mind, as the labelling algebras of our labelled deduction systems. The "truth-values as labels" approach allows us to give generalized systems for multiple-valued logics within the same formalism: since we can take multiple-valued logics as meaning not only finitely or infinitely many-valued logics but also power-set logics, i.e. logics for which the denotation of a formula can be seen as a set of worlds, our recipe allows us to capture also logics such as modal, intuitionistic and relevance logics, thus providing a first step towards the fibring of these logics with many-valued ones.