While specifications and verifications of concurrent systems employ Linear Temporal Logic
(LTL), it is increasingly likely that logical consequence in LTL will be used in the description …

A projective unifier for a modal formula A, over a modal logic L, is a unifier σ for A (ie a
substitution making A a theorem of L) such that the equivalence of σ with the identity map is …

We investigate logical consequence in temporal logics in terms of logical consecutions, ie,
inference rules. First, we discuss the question: what does it mean for a logical consecution to …

This chapter is a continuation of the preceding one, and we begin it at the place where the
authors of Basic Modal Logic left us about fifteen years ago. Concluding his historical …

In this work we study the notions of structural and universal completeness both from the
algebraic and logical point of view. In particular, we provide new algebraic characterizations …

We study an extension ℒƬℒ K of the linear temporal logic ℒƬℒ K by implementing multi-
agent knowledge logic KD45 m (which is often referred as multi-modal logic S5 m). The …

A quasivariety K of algebras has the joint embedding property (JEP) if and only if it is
generated by a single algebra A. It is structurally complete if and only if the free ℵ0 …

A deductive system is said to be structurally complete if its admissible rules are derivable,
and moreover is hereditarily structurally complete if all its finitary extensions are structurally …

We characterize all finitary consequence relations over S4. 3, both syntactically, by
exhibiting so-called (admissible) passive rules that extend the given logic, and semantically …

We discuss some of Jankov's contributions to the study of intermediate logics, including the
development of what have become known as Jankov formulas and a proof that there are …