Non-monotonic logics are among the most important calculi in the area of knowledge representation and reasoning. Autoepistemic logic, introduced 1985 by Moore [Moore 1985], is one of the most prominent non-monotonic logics. It was originally created to overcome difficulties present in the non-monotonic modal logics proposed by McDermott and Doyle [McDermott and Doyle 1980], but was also shown t...

We present an overview on how to perform non-monotonic reasoning based on paraconsistent logics. In particular, we show that one can define a logic programming semantics based on the paraconsistent logic G’3 which is called G’3-stable semantics. This semantics defines a frame for performing non-monotonic reasoning in domains which are pervaded with vagueness and inconsistencies. In fact, we sho...

This paper concentrates on comparing the relative expressive power of ve non-monotonic logics that have appeared in the literature. The results on the computational complexity of these logics suggest that these logics have very similar expressive power that exceeds that of classical monotonic logic. A reened classiication of non-monotonic logics by their expressive power can be obtained using t...

The present prolegomena consist, as all indeed do, in a critical discussion serving to introduce and interpret the extended works that follow in this book. As a result, the book is not a mere collection of excellent papers in their own specialty, but provides also the basics of the motivation, background history, important themes, bridges to other areas, and a common technical platform of the p...

We propose an alternative non-monotonic modal formalism called non-monotonic modal logic of belief. It is based on replacing the classical fixpoint equation E = ThS(A ∪ {Mφ : E 6`S ¬φ}) with the belief fixpoint equation E = ThS(A ∪ {Mφ : E 6`S ¬Mφ}). The solutions of the belief fixpoint equation, called belief S-expansions, are tightly related to the logic of belief KD45. We show interpretation...

This paper presents a formal theory of multiple agent non-monotonic reasoning. We introduce the subject of multiple agent non-monotonic reasoning for inquiry and motivate the field in terms of its applications for con-n-nonsense reasoning. We extend Moore’s [1985] Autoepistemic Logic to the multiple agent case, and show that the resulting logic is too weak for most applications of commonsense r...

Information integration systems providing the user with transparent access to heterogeneous data sources through a unified global view of all data, have emerged as a crucial issue in many application domains. This global view usually comprises integrity constraints which should be satisfied by the data retrieved from the sources. However, they might be often violated, and suitable approaches fo...

In this paper we present a purely semantic view on non-monotonic reasoning. We follow the direction pointed in [16] and claim that any non-monotonic logic can be viewed as a result of transforming some base standard logic by a selection strategy defined on models. The generalized theory of model preference is shortly outlined here together with its use in modeling non-monotonic beliefs.