Sound and complete modal propositional logic C is presented, in which 2P has the interpretation “ P is true in all states”. The interpretation is already known as the Carnapia...
abstract. The aim of the present paper is to analyze the complexity of strict implication (together with falsum, conjunction and disjunction). We prove that Ladner's Theorem r...
The aim of the TABLEAUX-2000 Non-Classical (Modal) System Comparisons (TANCS-2000) is to provide a set of benchmarks and a standardized methodology for the assessment and compariso...
Hybrid languages are extended modal languages which can refer to (or even quantify over) states. Such languages are better behaved proof theoretically than ordinary modal languages...