Inverses for Normal Modal Operators

Given a 1-ary sentence operator , we describe L - another 1-ary operator - as as a left inverse of in a given logic if in that logic every formula is provably equivalent to L. Similarly R is a right inverse of if is always provably equivalent to R. We investigate the behaviour of left and right inverses for taken as the operator of various normal modal logics, paying particular attention to the conditions under which these logics are conservatively extended by the addition of such inverses, as well as to the question of when, in such extensions, the inverses behave as normal modal operators in their own right.     

A Nonmonotonic Modal Formalization of the Logic of Acceptance and Rejection

The problems we deal with concern reasoning about incomplete knowledge. Knowledge is understood as ability of an ideal rational agent to make decisions about pieces of information. The formalisms we are particularly interested in are Moore's autoepistemic logic (AEL) and its variant, the logic of acceptance and rejection (AEL2). It is well-known that AEL may be seen as the nonmonotonic KD45 modal logic. The aim is to give an appropriate modal formalization for AEL2.     

Intuitionistic Autoepistemic Logic

In this paper we address the problem of combining a logic with nonmonotonic modal logic. In particular we study the intuitionistic case. We start from a formal analysis of the notion of intuitionistic consistency via the sequent calculus. The epistemic operator M is interpreted as the consistency operator of intuitionistic logic by introducing intuitionistic stable sets. On the basis of a bimodal structure we also provide a semantics for intuitionistic stable sets.     

Rules of Existential Quantification into "Intensional Contexts"

Propositional and notional attitudes are construed as relations (-in-intension) between individuals and constructions (rather than propositrions etc,). The apparatus of transparent intensional logic (Tichy) is applied to derive two rules that make it possible to export existential quantifiers without conceiving attitudes as relations to expressions (sententialism).     

Simulation and Transfer Results in Modal Logic – A Survey

This papers gives a survey of recent results about simulations of one class of modal logics by another class and of the transfer of properties of modal logics under extensions of the underlying modal language. We discuss: the transfer from normal polymodal logics to their fusions, the transfer from normal modal logics to their extensions by adding the universal modality, and the transfer from normal monomodal logics to minimal tense extensions. Likewise, we discuss simulations of normal polymodal logics by normal monomodal logics, of nominals and the difference operator by normal operators, of monotonic monomodal logics by normal bimodal logics, of polyadic normal modal logics by polymodal normal modal logics, and of intuitionistic modal logics by normal bimodal logics.     

Fuzzy Logic and Arithmetical Hierarchy,II

A very simple many-valued predicate calculus is presented; a completeness theorem is proved and the arithmetical complexity of some notions concerning provability is determined.     

Polanyi's Finalism

Although Michael Polanyi's model of science and his construal of the nature of the real are usually thought to be congenial to religion and although Polanyi himself says that "the stage on which we thus resume our full intellectual powers is borrowed from the Christian scheme of Fall and Redemption" (Polanyi 1958, 324), theologians have given little attention to the model of God he presents. The metaphysical and theological vision unfolded in part 4 of Personal Knowledge is a thoughtful alternative to materialist versions of neo-Darwinism and provides a platform for revisiting four long-standing controversies at the interface of science and religion: whether life and mind can be completely specified in terms of physical analysis, whether nature can be adequately understood without appeal to final causes, whether natural selection adequately explains life's diverse forms, and whether knowledge can be fully objectified. Through an exploration of Polanyi's contribution to these discussions, we undertake to show not only that his treatment of God as a cosmic field is strikingly original but also that in reinstating activity as a metaphysical category, he reconstructs our understanding of our creaturely hope and calling.     

THE DOCTRINE OF THE TRINITY AS A MODEL FOR STRUCTURING THE RELATIONS BETWEEN SCIENCE AND THEOLOGY

Abstract. A strategy for deeding systematically with such complex relationships as those between science and theology is presented after a brief overview of the historical record and illustrated in terms of the concept of divinity. The application of that strategy to the title relationships yields a multilogical/multilevel solution which presents certain analogies to or isomorphisms with the doctrine of the Trinity. These concern mainly the multilogical/multilevel character of both conceptualizations and the relational and contextual reasoning required to conceive them. Furthermore, certain characteristics of the doctrine facilitate the dialogue between theologians and scientists on account of their similarity with such scientific concepts as diversity in unity, multiplicity of relationships, nonseparability, and nonclassical logic.     

The logics of orthoalgebras

The notion of unsharp orthoalgebra is introduced and it is proved that the category of unsharp orthoalgebras is isomorphic to the category of D-posets. A completeness theorem for some partial logics based on unsharp orthoalgebras, orthoalgebras and orthomodular posets is proved.