-
Fitch's 'paradox of the Knower' shows that verificationism in the
appealing version "everything that is true may be known" is
inconsistent. We give an even stronger dynamic version: "everything
that is true may come to be known", and point out its connections with
the 'learning problem' for state...
-
We describe ongoing research to support the construction of
terminologies with Description Logics. Both in explanation of
subsumption and in learning of terminologies we search for particular
concepts because of their syntactic and semantic properties. More
precisely, the set of explanations for ...
-
Monotonic modal logics form a generalisation of normal modal logics in
which the additivity of the diamond modality has been weakened to
monotonicity: <>p \/ <>q --> <>(p \/ q).
This generalisation means that Kripke structures no longer form an
adequate semantics. Instead monotonic modal logics...
-
We prove that every normal extension of the bi-modal system
${\bf S5}^2$ is finitely axiomatizable and that every proper normal
extension has NP-complete satisfiability problem.
-
-
It has become increasingly clear that natural phenomena cannot be
formally deduced from laws but that almost every phenomenon has its
own particular way of being linked to higher-level generalizations,
usually via approximations, normalizations and corrections. This paper
centers around the follo...
-
We analyse the use of predicate minimization as a logical device,
determining the circumstances when it is appropriate in both semantic
and syntactic terms . Our main result here is a syntactic
characterization of all first-order formulas satisfying a semantic
property of predicate intersection. ...
-
The Dynamic Turn in logic makes actions of communication and general
information update into explicit objects of investigation. This paper
is a brief tour of this research program in a new version, bringing
together ideas from logic, philosophy, computer science, and game
theory. In particular, w...
-
This paper is an introduction to the volume FotFS III edited
by B. L\"owe, B. Piwinger and Th. R\"asch. The notions of
reduction functions and their derived complexity classes are
introduced abstractly and connected to the areas covered in the
mentioned volume.
-
We look at bimodal logics interpreted by cartesian products
of topological spaces and discuss the validity of certain
bimodal formulae in products or so-called cardinal spaces.
This solves an open problem of van Benthem et al.
-
Let $V$ be a variety of monotone bounded lattice expansions, that is,
lattices endowed with additional operations, each of which is order
preserving or reversing in each coordinate.
We prove that if $V$ is closed under MacNeille completions, then it is also
closed under canonical extensions.
As a...