5 papers · 1 filter
Ultrafilter Extensions for Veltman Semantics
Fèlix Frigola González, Joost J. Joosten, Vicent Navarro Arroyo +1
In this paper, we present a first-order frame condition for interpretability logic and show that the condition is not modally definable. Yet, the frame condition holds both on ILM…
Completeness and Incompleteness for Expanding Gödel-Löb Logics
Somayeh Chopoghloo, David Fernández-Duque, Joost J. Joosten +1
Expanding products of modal logics are bimodal logics obtained from the combination of a `horizontal component' logic and a `vertical component' logic, lying between the fusion and…
On the Contingency of Logic in Possible World Semantics
Iris van der Giessen, Joost J. Joosten, Paul Mayaux +1
This paper investigates the contingency of logic within the framework of possible world semantics. Possible world semantics captures the meaning of necessitation, i.e., a statement…
The Provably Total Set-Recursive Functions of KPl
Juan Pablo Aguilera, Anton Fernández, Joost J. Joosten
Using relativized ordinal analysis, we give a proof-theoretic characterization of the provably total set-recursive-from- functions of KPl and related theories.
A tree rewriting system for the Reflection Calculus
SofÃa Santiago-Fernández, Joost J. Joosten, David Fernández-Duque
The () is the fragment of the polymodal logic in the language whose formulas are built up from …