Nen assentives and the phenomenon of dialogic parallelisms

A task for ontolinguistics is to delimit the set of grammatical devices sensitive to the speech-act nexus – whether speech-act role (speaker, hearer, etc.), knowledge asymmetries (ignoratives and demonstratives), speech-act goals (imperatives, questions, etc.), or social relations (e.g. honorifics). These devices are co-constructed by speaker-hearer dyads, and a convincing framework for dealing with them needs a typology of dialogic parallelisms: grammatical constructions in which there are tight formal and grammatical links between the contributions of the two parties. In the first part of this chapter I survey a number of known phenomena, including interrogative-demonstrative parallelisms, question-answer parallels, and conjunct/disjunct systems. In the second part I introduce a further, previously unreported example of dialogic parallelisms: assentives are a category used to supply assenting answers to imperatives. In the Papuan language Nen these show tight formal parallels to imperatives. I conclude by arguing for the need for greater attention to dialogic coordination in the shaping of core grammatical morphology.