Implicit Arguments: Event Modification or Option Type Categories?

We propose a unified syntactic-semantic account of passive sentences and sentences with an unspecified object (John read). For both constructions, we employ option types for introducing implicit arguments into the syntactic-semantic categorial mechanism. We show the advantages of this approach over previous proposals in the domains of scope and unaccusatives. Unlike pure syntactic treatments, option types immediately derive the obligatory narrow scope of existential quantification over an implicit argument’s slot. Unlike purely semantic, eventbased treatments, our proposal naturally accounts for syntactic contrasts between passives and unaccusatives, as in the door *(was) opened by John.