The role of the conservative learner in the rise and fall of verb-second

This paper argues that the diachronic rise and fall of verb-second grammars is tied to the conservative nature of child structure projection and movement postulation, within a Minimalist syntax. For the rise of V2, we propose that children bundle features on a single head in the left periphery, only unbundling (adding projections) with unequivocal input evidence. For the loss of V2, we appeal to the theory that children avoid verb movements, only postulating additional movements with unequivocal input evidence. Interim grammars along the developmental path – with bundled left peripheries or less-moved Vs relative to the input grammars – prescribe latent diachronic pathways available to actuate into community grammars. We assess our predictions for child interim grammars against the acquisition literature and find data consistent with both fewer projections and less movement in child language, relative to adult input grammars. We appeal to changes in the learning context, namely bilingualism in language contact, as the external impetus for the actuation of change, in both our V2 case studies (Rise: Old French, Loss: Germanic Urban Vernaculars). In language contact situations we suggest children are more likely to continue to use interim grammars for longer periods among their peer-groups, inviting innovative syntax to catch-on (or actuate) among young speakers in those speech communities.