Temporal Existentials and the Amount Perfect

This paper examines new data concerning the Perfect aspect and its modification by since clauses. Past analyses of such adverbials have argued that the complement of since can be a clause expressing an event, but that the event must be unique (Iatridou 2003); and that the complement can be a Universal Perfect, but not an Existential Perfect (von Fintel and Iatridou, in progress). However, the sentence It has been four years since Henry has visited the MIT Museum is grammatical and felicitous, even though there are presumably many events of Henry visiting the MIT Museum and even though and even though the complement of the since clause is an E-Perfect and not a U-Perfect. Such data presents a challenge for previous conceptions of the Perfect. In this paper, I propose a new Amount Perfect meaning for the Perfect morpheme that accounts for temporal existentials (with unique events in the embedded clause) by relating them to simultaneous reading sentences (with Universal Perfects in the embedded clause). 1