Agree probes down: Anaphoric feature valuation and phase reference

This paper investigates the question of the directionality of Agree in the domain of complementizer agreement (CA). Germanic and Bantu patterns of CA provide prima facie evidence of both downward and upward-probing relations, as Ger- manic complementizers are valued by the subject of the embedded clause, whereas the relevant Lubukusu complementizers are valued by the subject of the main clause. We argue, however, that all feature valuation relations can be explained by a downward-probing Agree operation. Apparent instances of upward-probing feature-valuation are analyzed as anaphoric feature valuation, which is a compos- ite operation consisting of movement of the relevant (unvalued, interpretable) fea- tures followed by probing of their c-command domain for valuation. We propose that the behavior of anaphoric features can be derived from more fundamental syn- tactic properties using a model of syntax that relies on the referential properties of phases: more rigid reference of a phase is derived by movement of phase-internal elements to the edge of that phase.