Year: 2025
Type: article
Abstract: We consider a modal logic that can formalise statements about uncertainty and beliefs such as I think that my wallet is in the drawer rather than elsewhere or I am confused whether my appointment is on Monday or Tuesday.To do that, we expand Gödel modal logic KG with the involutive negation ∼ defined as v(∼φ , w) = 1v(φ , w).We provide semantics with the finite model property for our new logic that we call KG inv and show its equivalence to the standard semantics over [0, 1]-valued Kripke models.Namely, we show that φ is valid in the standard semantics of KG inv iff it is valid in the new semantics.Using this new semantics, we construct a constraint tableaux calculus for KG inv that allows for an explicit extraction of countermodels from complete open branches and then employ the tableaux calculus to obtain the PSPACE-completeness of the validity in KG inv .
DOI: 10.4204/eptcs.437.20
Language: English
Subfield: Artificial Intelligence
Field: Computer Science
Domain: Physical Sciences
Open Access status: diamond
OpenAlex ID: W4416664995
