Towards a dynamic functional proposition for dynamic discourse meaning

Theories of utterance meaning in the post-Gricean tradition have typically focused on the main proposition expressed by the speaker that is recovered by the addressee. In this tradition, successful communication rests on the assumption that speakers and addressees come to a shared understanding of these propositions as they are produced in conversation. We now have a wealth of empirical evidence that speakers and addressees need not always converge on the main proposition expressed in order for communication to proceed unhindered: they may share partial understandings of individual utterances, allowing the overarching discourse meaning to unravel as the interaction progresses. In this paper, we propose a novel unit of meaning that accounts for such a dynamic concept that can emerge and develop over several turns at talk. We call it a ‘dynamic functional proposition’. This unit includes not only the linguistic meaning that has been communicated, but also meaning conveyed through non-linguistic sources, as well as aspects of situation captured through what we call ‘filters’, such as interlocutors’ levels of attention, emotions, and other non-representational aspects. These various aspects will have greater or lesser salience for different speakers, hence offering an explanatory tool for how utterance meanings are negotiated, as well as when and why misunderstandings occur. We finish by proposing ways in which such a unit can be formally represented. We do this by motivating different cognitive, social and linguistic parameters that influence it.