A useful logic in which to specify normative system behaviour, deontic logic has a broad spectrum of possible applications within the field: from legal expert systems to natural language processing, database integrity to electronic contracting and the specification of fault-tolerant software.

This book constitutes the refereed proceedings of the 7th International Workshop on Deontic Logic in Computer Science, DEON 2004, held in Madeira, Portugal, in May 2004. The 15 revised full papers presented together with the abstracts of 2 invited talks were carefully reviewed and selected for inclusion in the book. The papers are devoted to the relationship between normative concepts and computer science, artificial intelligence, organization theory, and law; in addition to these topics, special emphasis is placed on the relationship between deontic logic and multiagent systems.

This volume presents the papers contributed to ?EON 2008, the 9th Inter- tional Conference on Deontic Logic in Computer Science, held in Luxembourg, July 16–18, 2008. This biennial conference series is designed to promote int- national cooperation amongst scholars who are interested in deontic logic and its use in computer science. The scope of the conference is interdisciplinary, and includes research that links the formal-logical study of normative concepts and normative systems with computer science, arti?cial intelligence, philosophy, - ganization theory, and law. The ?EON website, http://www.deonticlogic.org, contains links to previous conferences and their papers. This history reveals a vibrant interdisciplinary research program. Papers for these conferences might address such general themes as the - velopment of formal systems of deontic logic and related areas of logic, such as logics of action and agency, or the formal analysis of all sorts of normative concepts, such as the notions of rule, role, regulation, authority, power, rights, responsibility, etc., or the formal representation of legal knowledge. They might also be concerned with applications, such as the formal speci?cation of n- mative multiagent systems, the speci?cation of systems for the management of bureaucratic processes in public or private administration, or the speci?cation of database integrity constraints or computer security protocols, and more. Of particular interest is the interaction between computer systems and their users.

This book constitutes the refereed proceedings of the 8th International Workshop on Deontic Logic in Computer Science, DEON 2006, held in Utrecht, Netherlands in July 2006. Presents 18 revised full papers together with the abstracts of 3 invited talks. The papers are devoted to the relationship between normative concepts and computer science, artificial intelligence, philosophy, organization theory, and law. Special emphasis is placed on artificial normative systems.

This book describes extensions of deontic logic. Deontic logic is a branch of philosophical logic involving reasoning with norms, obligations, prohibitions and permissions. The extensions concern the logical structure of legal rules and legal reasoning. Their function is to improve the representation of legal knowledge and enhance deontic logic through increased expressibility. The resulting formulas acquire new meanings, not expressible in standard deontic logic, which are subject to fresh interpretations. The author offers an extensive analysis of the representation of actors, to whom the norms are directed, and authorities who enact the norms. Moreover, a distinction is made between enactment and applicability. A modality of enactment can be used to express inconsistent enacted norms in a consistent way. An authority-hierarchy is introduced to filter out the applicable norms from the set of enacted norms. Some related philosophical questions will be discussed regarding the applications of formalisms that are intrinsic to practical science with respect to `consistency' and `universality'. The formalisms and applications considered here are relevant for law, philosophy and computer science, with a special focus on the improvement of legal expert systems and intelligent support for legal professionals.

This book presents research in an interdisciplinary field, resulting from the vigorous and fruitful cross-pollination between traditional deontic logic and computer science. AI researchers have used deontic logic as one of the tools in modelling legal reasoning. Computer scientists have discovered that computer systems (including their interaction with other computer systems and with human agents) can often be productively modelled as norm-governed. So, for example, deontic logic has been applied by computer scientists for specifying bureaucratic systems, access and security policies, and soft design or integrity constraints, and for modelling fault tolerance. In turn, computer scientists and AI researchers have also discovered (and made it clear to the rest of us) that various formal tools (e.g. nonmonotonic, temporal and dynamic logics) developed in computer science and artificial intelligence have interesting applications to traditional issues in deontic logic. This volume presents some of the best work done in this area, with the selection at once reflecting the general interdisciplinary (and international) character that this area of research has taken on, as well as reflecting the more specific recent inter-disciplinary developments between traditional deontic logic and computer science.