Case splits and the order of elementary operations

In this paper I propose a unified account for both local and global case splits in terms of local impoverishment. My main claim is that impoverishment takes place within narrow syntax and may thus interact with the operation Agree. This reassessment of the place of impoverishment in the grammar has the immediate consequence that Agree may apply after impoverishment. Such ‘late’ Agree may then percolate the effects of local impoverishment within the structure, giving rise to the impression of non-local mechanisms at work. A second, logically independent, claim is that impoverishment is brought about by harmonic alignment of Silverstein hierarchies. The paper is structured as follows: Section 1 lays the empirical groundwork by exemplifying local and global case splits and showing that they adhere to the same generalization. Section 2 introduces the theoretical background assumptions and puts forth my proposal. Sections 3 and 4 put the account to work on local and global splits, respectively. Section 5 illustrates an empirical prediction of the proposed system regarding the interaction of local and global splits with verbal agreement. Finally, section 6 draws the conclusion.