A dialogue game for dialectical interaction with expert systems

In a variety of applications the most appropriate model of interaction with a knowledge based system is the dialectical discussion, in which a proposition is proposed and argued for. In the course of such a dialogue the tenability of the proposition will be established and the argu-ments in favour of it adduced and refined. To enable such an interaction it is necessary to for-malise the principles underlying such dialogues in a way from which rules to govern system behaviour can be derived. In this paper we argue that the analysis of arguments given by Stephen Toulmin represents a good starting point, and propose a dialogue game based on this schema, adapted to the needs of knowledge based systems. We then sketch an implementation of this game which would provide an interface to a knowledge based system in which queries, their answers and explanations were interleaved in a manner akin to an interpersonal discus-sion. Such an interface could be used both to interrogate the knowledge base and, if desired, to extend and modify the rules of the knowledge base