We give a sound and complete propositional S5 tableau system of a particularly simple sort, having an easy completeness proof. It sheds light on why the satisfiability problem for...
We describe a new way to construct large subdirectly irreducibles within an equational class of algebras. We use this construction to show that there are forbidden geometries of m...
We propose an extension of answer sets, that we call safe beliefs, that can be used to study several properties and notions of answer sets and logic programming from a more genera...
Coalgebra develops a general theory of transition systems, parametric in a functor T; the functor T specifies the possible one-step behaviors of the system. A fundamental question...