In this paper we compare the expressive power of elementary representation formats for vague, incomplete or conflicting information. These include Boolean valuation pairs introduced by Lawry and Gonzalez-Rodriguez, orthopairs of sets of variables, Boolean possibility and necessity measures, three-valued valuations, supervaluations. We make explicit their connections with strong Kleene logic and...

Several interpretations can be given to the third truth value in three-valued logics. Here, we consider the case when it refers to the epistemic notion of contradictory, or both true and false at the same time. We study several paraconsistent threevalued logics that carry this concern and show that they can be translated into a fragment of a simple epistemic logic where modalities can only appe...

In this paper we deal with quasivarieties of residuated structures which form the equivalent algebraic semantics a positive fragment some substructural logic. Our focus is mainly on varieties and Wajsberg hoops, are Łukasiewicz many-valued particular study lattice subquasivarieties hoops describe completely all subvarieties that primitive. Though treatment mostly in nature, there obvious connec...

This paper addresses the problem of probabilistic reasoning as it applies to Truth Maintenance Systems. A Belief Maintenance System hal! been constructed which manages a current set of probabilistic beliefs in much the same way that a TMS manages a set of true/false beliefs. Such a system may be thought of as a generalization of a. Truth Maintenance System. It enables one to reason using normal...

Bilattices and d-frames are two different kinds of structures with a four-valued interpretation. Whereas d-frames were introduced with their topological semantics in mind, the theory of bilattices has a closer connection with logic. We consider a common generalisation of both structures and show that this not only still has a clear bitopological semantics, but that it also preserves most of the...

We study clones on a four-element set related to the clone $${\mathsf {DMA}}$$ of all term functions subdirectly irreducible De Morgan algebra $${\mathbf {DM}}_{{{\mathbf {4}}}}$$ . find generating sets for preserving subalgebras , automorphisms truth order and information as well defined by conjunctions these conditions. identify covers in lattice four-valued describe above which contain discr...

It is argued that the ‘inner’ negation ∼ familiar from 3-valued logic can be interpreted as a form of ‘conditional’ negation: ∼A is read “A is false if it has a truth value”. It is argued that this reading squares well with a particular 3-valued interpretation of a conditional that in the literature has been seen as a serious candidate for capturing the truth conditions of the natural language ...