It is a standard feature of norm-governed institutions that designated agents are empowered to create particular kinds of states of affairs by means of the performance of specified types of actions. Frequently, the states of affairs are of a normative kind, in the sense that they pertain to rights and obligations, as for instance when a Head of Department signs a purchase agreement and thereby creates an obligation on his employer to pay for goods received. We use the term institutionalised power to stand for the notion of power we here seek to explicate. Following a lead from jurisprudential discussions of legal power, we distinguish institutionalised power from permission and practical possibility. We define a conditional connective intended to capture the consequence relation implicit in statements of the form: according to the constraints operative in institution s, the performance of some act A by agent x counts as a means of creating state of affairs B. When combined with deont...

The Kanger-Lindahl theory of normative positions attempts to use a combination of deontic logic (the logic of obligation and permission) and a logic of action/agency to give a formal account of obligations, duties, rights, and other complex normative concepts. This paper presents a generalisation and further development of this theory, together with methods for its automation and application to practical examples. The resulting theory is intended to be applied in the representation and analysis of laws, regulations, and contracts, in the specification of aspects of computer systems, in multi-agent systems, and as a contribution to the formal theory of organisations. Particular attention is paid to representations at varying levels of detail and the relationships that hold between them. The last part presents Norman-G, an automated support system intended to facilitate application of the theory to the analysis of practical problems, with a small example to illustrate its use.

This paper provides a formal framework for developing the idea of normative co-ordination. This idea is based on the assumption that agents can achieve flexible co-ordination by conferring normative positions to other agents. These positions include duties, permissions, and powers. In particular, we introduce the idea of declarative power, i.e. the capacity of the power-holder of creating normative positions by simply "proclaiming" such positions. We account also for the concepts of representation -- the representative's capacity of acting in the name of his principal --, and mandate -- the mandatee's duty to act as the mandator has requested.

Abstract. In this paper we provide a formal framework for developing the idea of normative co-ordination. We argue that this idea is based on the assumption that agents can achieve flexible co-ordination by conferring normative positions to other agents. These positions include duties, permissions, and powers. In particular, we introduce the idea of declarative power, which consists in the capacity of the power-holder of creating normative positions, involving other agents, simply by “proclaiming” such positions. In addition, we account also for the concepts of representation, consisting in the representative’s capacity of acting in the name of his principal, and of mandate, which corresponds the mandatee’s duty to act as the mandator has requested. 1

Electronic markets, dispute resolution and negotiation protocols are three types of application domains that can be viewed as open agent societies. Key characteristics of such societies are agent heterogeneity, conflicting individual goals and unpredictable behaviour. Members of such societies may fail to, or even choose not to, conform to the norms governing their interactions. It has been argued that systems of this type should have a formal, declarative, verifiable, and meaningful semantics. We present a theoretical and computational framework being developed for the executable specification of open agent societies. We adopt an external perspective and view societies as instances of normative systems. In this paper we demonstrate how the framework can be applied to specifying and executing a contract-net protocol. The specification is formalised in two action languages, the C+ language and the Event Calculus, and executed using respective software implementations, the Causal Calculator and the Society Visualiser. We evaluate our executable specification in the light of the presented case study, discussing the strengths and weaknesses of the employed action languages for the specification of open agent societies.

A normative system is defined as any set of interacting agents whose behavior can usefully be regarded as norm-directed [9]. Most organizations, and more specifically institutions, fall under this definition. Interactions in these normative systems are regulated by normative templates that describe desired behavior in

This paper presents a deontic logic \Sigma for reasoning about per- mission or prohibition to know some parts of the datab!ase content in the context of a multilevel confidentiality policy. The most important logical features in the definition of a multi- level policy are that each confidentiality level is defined by a set of sentences and that, when the policy is designed, the permission to know is not necessarily the complement of the prohibition to know. These concepts are formalized in a modal logic where deontic modalities, doxastic modalities and confidentiality levels are interpreted by non-standard modal models. The corresponding axiomatics is also presented in the paper and its soundness and completeness have been proved. A limitation of the \Sigma logic is that sentences in the scope of modalities are sentences of Propositional Calculus. Finally, it is shown how the logic can be used to express con- straints to guarantee the consistency of a policy or to prevent the existence of inference channels. That is, the possibility to infer sen- tences that are not permitted to know from other sentences that are permited to know. Both deductive and abductive channels are considered. Keywords: knowledge representation, deontic logic, database security.

Abstract. We present a modal logic called LIA (Logic of Intention and Attempt) in which we can reason about intention dynamics and intentional action execution. By exploiting the expressive power of LIA, we provide a formal analysis of the relation between intention and action and highlight the pivotal role of attempt in action execution. Besides, we deal with the problems of instrumental reasoning and intention persistence.

The theory of normative positions attempts to apply a combination of deontic logic and a logic of action/agency to the formalisation of the `Hohfeldian concepts' (duty, right, power, privilege, etc.) and other complex normative relations between agents. This paper is concerned with the practical applicability of the theory to such tasks as formalising the content of an existing set of regulations, designing a new set of regulations, or rening aspects of a computer system specication, with particular attention to the usefulness of the action component as a representational device. Points are made by reference to a simple example concerning rules in a car park. The second part of the paper covers three simple extensions: the representation of `permitted to bring about', a treatment of interpersonal control relations, and the ability to distinguish between being permitted to bring about a new state of aairs and being permitted to sustain a state of aairs that already exists...

In this paper, we are interested in formally modeling the concept of responsibility. It appears that this concept is essential in order to reason in many norm-governed organizations. However, obtaining a formal representation of responsibility is quite complex because of the very different meanings this concept can take. Therefore, our first task will be to clarify and classify the various meanings. We then propose a logical framework and show how it enables us to model several aspects of responsibility. This framework combines a deontic logic with a logic of actions and it distinguishes between direct and indirect agencies. We finally present an example to illustrate how this framework enables us to analyze some subtleties of a specific situation. Keywords: Representation of Legal Knowledge, Deontic Logic, Logic of Action. 1 Introduction The concept of responsibility is central to all legal systems and other norm-governed organizations. Analyzing this concept is therefore fundamenta...