Joint innovation: An alternative to the initiation-diffusion and speaker-listener dichotomies in language change

In this contribution we examine current views of the relationship between innovation on the one hand, and diffusion of a change through a community on the other. We also note in the recent literature much discussion of the role of the listener vs. the role of the speaker in innovation and spread. This paper re-examines the dichotomies just mentioned — innovation vs. spread and speaker vs. listener — and finds them unjustified. We consider two types of change — sound change and grammaticalization — which are similar in that they both show directional patterns across time and across languages, and they are both considered to be gradual. Based on empirical evidence from a wide range of studies from interactional linguistics, sociolinguistics, and diachronic linguistics, we argue that innovation occurs jointly between speaker and listener in the same speech community and spreads gradually on all dimensions.