Argument Structure and Unaccusativity in the Constraint-based Lexicon

This paper addresses the issue of Split Intransitivity (si) and Unaccusative Mismatches (uMs), proposing a constraint-based approach to si and ums within a recent framework of Head-driven Phrase Structure Grammar. I argue against the widely accepted dichotomous distinction of intransitive verbs, which has been advanced by the Unaccusative Hypothesis [Perlmutter (1978)]. I then propose a quadripartitive distinction of intransitive verbs on the basis of the distribution of subject argument in the semantically motivated argument structure, and show that this quadripartitive distinction allows a better understanding of si and ums. The main idea of this proposal will be summarized as the Quadripartitive Split Intransitivity Hypothesis (Qsm).