Minimality, Non-Determinism, and Absent Information in Multi-Context Systems

Multi-context systems (MCS) can be used to represent contextual information flow. We show that the semantics of an MCS is completely determined by the information that is obtained when simulating the MCS, in such a way that a minimal amount of information is deduced at each step of the simulation. The MCS framework implicitly presupposes that information flow is deterministic. In many natural situations, this is not a valid assumption. We propose an extension of the framework to account for non-determinism and provide an algorithm to efficiently compute the meaning of non-deterministic systems. In MCS, the acquisition of new information is based on the presence of other information only. We give a generalized account to model situations in which information is obtained as a result of the absence of other information.