Abstract
Prominence hierarchy effects such as the animacy hierarchy and definiteness hierarchy have been a puzzle for formal treatments of case since they were first described systematically in Silverstein 1976. Recently, these effects have received more sustained attention from generative linguists, who have sought to capture them in treatments grounded in well-understood mechanisms for case assignment cross-linguistically. These efforts have taken two broad directions. In the first, Aissen 1999, 2003 has integrated the effects elegantly into a competition model of grammar using OT formalisms, where iconicity effects emerge from constraint conjunctions between constraints on fixed universal hierarchies (definiteness, animacy, person, grammatical role) and a constraint banning overt morphological expression of case. The second direction grows out of the work of Jelinek and Diesing, and is found most articulated in Jelinek 1993, Jelinek and Carnie 2003, and Carnie 2005. This work takes as its starting point the observation that word order is sometimes correlated with the hierarchies as well, and works backwards from that to conclusions about phrase structure geometries. In this paper, I propose a particular implementation of this latter direction, and explore its consequences for our understanding of the nature of case assignment. If hierarchy effects are due to positional differences in phrase structures, then, I argue, the attested cross-linguistic differences fall most naturally out if the grammars of these languages countenance polyvalent case—that is, assignment of more than one case value to a single nominal phrase.