Rights and Argumentation in Open Multi-Agent Systems

As utility calculus cannot account for an important part of agents' behaviour in Multi-Agent Systems, researchers have progressively adopted a more normative approach. Unfortunately, social laws have turned out to be too restrictive in real-life domains where autonomous agents' activity cannot be completely specified in advance. It seems that a halfway concept between anarchic and off-line constrained interaction is needed. We think that the concept of right suits this idea. Rights improve coordination and facilitate social action in Multi-Agent domains.Rights allow the agents enough freedom, and at the same time constrain them (prohibiting specific actions). Besides, rights can be understood as the basic concept underneath open normativesystems where the agents reason about the code they must abide by. Typically, in such systems this code is underspecified. On the other hand, the agents might not have complete knowledge about the rules governing their interaction. Conflict situations arise, thus, when the agents have different points of view as to how to apply the code. We have extended Parsons's et al. argumentation protocol (Parsons et al. 1998a, b) to normative systems to deal with this problem.