We investigate the connection between the two major mathematical frameworks for modeling interactive beliefs: Harsanyi type spaces and possible-worlds–style probability frames. While translating the former into the latter is straightforward, we demonstrate that the reverse translation relies implicitly on a background logical language. Once this “language parameter” is made explicit, it reveals...

Many logics for AI applications that are defined by denotational semantics are trivialized in the presence of inconsistency. It is therefore often desirable, and practically useful, to refine such logics in a way that inconsistency does not cause the derivation of any formula, and, at the same time, inferences with respect to consistent premises are not affected. In this paper, we introduce a g...

According to the realistic approach to semantics the meaning of an expression is something out there in the world. In technical terms, a semantics for a language is seen as a mapping from the grammatical structures to things in the world (or in several possible worlds). Often meanings are defined in terms of truth conditions. A consequence of this approach is that the meaning of an expression i...

The analysis of extreme states of consciousness (perinatal experience and transpersonal experience) is outside the sphere of normal science. Experience goes beyond the empirically evidenced frames of consciousness and become transcendental towards rational manifestations. The author offers hypothesis of possible worlds with emphasis on the authenticity of the experience in the role of the facto...

This paper is concerned with the technical implications of a certain view connecting existence to predication. This is the view that in no possible world is there a genuine relation among the nonexistents of that world or between the nonexistents and the existents! The meaning of the term ‘genuine’ here may be variously explained. On an extreme interpretation, all relations are ‘genuine’, so th...

In this paper, the authors argue that there is a version of actualist realism about possible worlds and possible individuals that is immune to the difficulties raised for this view in Divers 2002. We show that object theory, as a form of actualist realism, provides a general theory of modality that is at least as good as genuine realism but without the commitment to possible worlds in David

We proposed a novel framework for the representation of goals and other mental-like attitudes in terms of degree of expected outcomes, where an outcome is an order of possible alternatives. The sequences of alternatives is modelled by a non-classical (substructural) operator. In this paper we provide a modal logic based axiomatisation of the intuition they propose, and we discuss some variants ...

The subject of this article is Modal-Epistemic Arithmetic, a theory introduced by Horsten to interpret Epistemic Arithmetic, which in turn was introduced by Shapiro to interpret Heyting Arithmetic. I will show how to interpret Modal-Epistemic Arithmetic in Epistemic Arithmetic and I will show how to get rid of a particular Platonist assumption. Then I will discuss models for Modal-Epistemic Ari...

Simple belief-revision tasks were defined by a giving subjects a conditional premise, (p—>q), a categorical premise, (p, for a modus-ponens belief-set, or ~q, for a modus tollens belief-set), and the associated inference (q or ~p, respectively). "New" information contradicted the initial inference (~ q or p, respectively). Subjects indicated their degree of belief in the conditional premise and...

Ordinary modal logic deals with the notion of a proposition being true in at least one possible world. This makes it natural to consider the notion of a proposition being true in n possible worlds for any nonnegative integer n. Such a notion would stand to Tarski’s numerical quantifiers as ordinary possibility stands to the existential quantifier. In this paper I present several logics for nume...