Decompositional Proof Systems for Logics Based on Non-deterministic Matrices

Abstract

Non-deterministic matrices (shortly: N-matrices) are multiple-valued
structures in which the value assigned by a valuation to a complex formula
can be chosen non-deterministically out of a certain nonempty set of options.
We consider two versions of semantics of a logic based on an N-matrix:
a dynamic one and a static one. The dynamic semantics corresponds to a fully
non-deterministic choice of the value of any connective within the set of
allowed options independently for each application of the connective
(computation time choice). The static valuation, in turn, amounts to
choosing beforehand, within the allowed set of options, one deterministic
application of the connective to be used in each application of the
connective (global choice). For each type of semantics, we develop
general deductive proof systems employing the R-S decomposition methodology
for logics propositional logics based on those structures. Later we show
how these systems can be used to obtain cut-free ordinary Gentzen calculi
for some well-known logics.