This paper contains a survey of the main definitions and results obtained to date related to Temporal Equilibrium Logic, a nonmonotonic hybrid approach that combines Equilibrium Logic (the best-known logical characterisation for the stable models semantics of logic programs) with Linear-Time Temporal Logic.

In this paper, we study the introduction of modal past temporal operators in Temporal Equilibrium Logic, an hybrid formalism that mixes linear-time modalities and logic programs interpreted under stable models and their characterisation in terms of Equilibrium Logic. We show that Kamp’s translation can also be used to translate the new extension of TEL with past operators into Quantified Equilibrium Logic. Additionally, we provide a method for removing past operators that consists in replacing past-time subformulas by fresh auxiliary atoms, obtaining (...) an equivalent formula, modulo the original alphabet. (shrink)

1. Reasoning about action and change, or more generally reasoning about dynamic systems, is not only central to knowledge representation and reasoning but at the heart of computer science (Fisher e...

Near the end of 2015, Luis Fariñas del Cerro officially retired as directeur de recherche in the Centre National de Recherche Scientifique (CNRS) and became an Emeritus researcher of the CNRS. The present special issue is a Festschrift in his honour to celebrate Luis’s achievements in science, both as an outstanding scholar as well as a remarkable and highly successful organiser, administrator and leader in science and technology policy and management, in particular as the founder of the Journal of Applied (...) Non-Classical Logics. The issue contains 13 scientific contributions by 32 authors, among them Luis’s colleagues, former students and friends. Preceding versions of these papers were presented at the international workshop ‘Logical Reasoning and Computation’ that was held at IRITInstitut de Recherche en Informatique de Toulouse, Université Paul Sabatier, Toulouse, on 3–4 March 2016. The present introduction contains a short scientific biography describing the many different areas of logic and computation where Luis contributed significant advances. (shrink)

We give an account of stable reasoning, a recent and novel approach to problem solving from a formal, logical point of view. We describe the underlying logic of stable reasoning and illustrate how it is used to model different domains and solve practical reasoning problems. We discuss some of the main differences with respect to reasoning in classical logic and we examine an ongoing research programme for the rational reconstruction of human knowledge that may be considered a successor to the (...) logical empiricists’ programme of the mid-twentieth century. (shrink)