Updating Mental States from Informative Communication

Effective and useful communication requires the agents` being able to foresee the effects of their utterances over the addressee`s mental state. However, referring to the classical Speech Act Theory, it seems that the idea of predicting such effects is rather optimistic since they are not really completely, a priori, foreseeable by the speaker. Along with some obvious main effects, there are other side effects which might be regarded as the result of some kind of plausible inference, particularly abduction, performed by the hearer herself on the basis of the received communication, over her own mental state and her image of the speaker`s mental state. In this paper we provide a formal representation of agents mental states, we propose a correlation between speaker`s mental state and his uttering a certain sentence, we provide a method based on abduction that the hearer can adopt to update her image of the speaker`s mental state as effect of a specific utterance performed by the speaker. Our approach is based upon the use of multi context systems extended with abduction and revision