Superficial Tableaux for Contextual Reasoning
Fabio Massacci · 1995
This paper presents a tableaux calculus for the Propo-sitional Logic of Contexts with the ist(c,¢) modal-ity. This approach has a twofold advantage: from the user viewpoint it presents rules which intuitively re-flect epistemic properties (lifting, use of assumptions etc.); from a computational perspective it allows local and incremental computation, satisfies strong conflu-ence and can therefore be adapted efficiently to dif-ferent search heuristics. The modelling of contexts as partial objects is obtained by using superficial as-signments. We can define meaningful and meaningless sentences and reason about formulae containing both kind of sentences. Superficial valuations provide us with a sound and incremental approximation of clas-sical logic and make it possible to present a simplified semantics based on layered models.