Decidable term-modal logics

The paper considers term-modal logics and introduces some decidable fragments thereof. In particular, two fragments will be introduced: one that simulates monotone non-normal logics and another one that simulates normal multi-agent epistemic logics with quantification over groups of agents. These logics are defined semantically. Then, each of them is proof-theoretically characterized by a labelled calculus with good structural properties. Finally, we prove that each fragment considered is decidable, and we characterize the complexity of the validity problem for some of them