Three ways to avoid commitments: Declarative force modifiers in the conversational scoreboard

Abstract

We discuss three English markers that modify the force of declarative utterances: reverse-polarity tags (Tom's here, isn't he?), same-polarity tags (Tom's here, is he?), and rising intonation (Tom's here?). The three are similar in that they seem to render the assertion expressed by the attached declarative tentative in some way. The differences among them are brought out especially clearly in dialogues with taste predicates (tasty, attractive) and vague scalar predicates applied to borderline cases (red for an orange-red object). These differences have consequences for the correct model of conversation, common ground, and speech acts. Our proposal involves a conversational 'scoreboard' that allows speakers to make strong or tentative commitments, propose changes or raise expectations about the Common Ground, propose issues to be resolved, and hazard guesses about other participants' beliefs. This model allows for distinctions among speech acts that are subtle and fine-grained enough to account for the behavior of these three markers.