Toward Rational Communicative Behavior

We view communicationas action aimedat increasing the efficiency of interaction amongmultiple agents. Thus, wepostulate that a speaker design a speech act so as to maximallyincrease the benefit it obtains as the result of the interaction. This paper presents a theoretical frameworkwhichcan be used by this kind of the design process. Ourframeworkconsists of a representation of an episteinic state of an agent engaged in an interaction, andincludes the agent's preferences, abilities andbeliefs aboutthe world,as well as the beliefs the agent has about the other agents, the beliefs the other agents have, and so on. Apragmatic meaning of a speechact can be then definedas a transformationit induces on the epistemic state of an agent. This transformation leads to a changein the quality of the interaction, expressedin termsof the benefit to the agent. Wepropose that a rational communicative behavior results from a speaker choosing to perform the speech act that maximizesthe expected increase in the quality of the interaction. In this paper we analyze questions, proposals and threats, imperatives, and statements of knowledgeand belief.