When Number Agreement Acts Like a Polarity Item: Disjunctive Agreement Across Semantic Environments

Do context or semantic environment ever affect agreement morphology? Yes, I argue in this talk. Examining number agreement with disjoined subjects in English — e.g., the difference between ‘Ann doubts that Bob or Cal is coming’ and ‘Ann doubts that Bob or Cal are coming’ — I show that verbal agreement with disjoined subjects is sensitive to semantic factors such as scope, monotonicity, and quantification. Though past analyses (Foppolo & Staub 2020, Himmelreich & Hartmann 2023, Krifka & Modarresi 2024, a.o.) have sought to derive free variation between singular and plural agreement, I argue, following Ivlieva (2013), that plural-agreeing disjunction is only acceptable in certain semantic environments, namely in polar questions and when scoping beneath certain quantifiers. I show that the environments in which disjoined subjects can control plural agreement are the same kinds of environments in which indefinites fail to introduce discourse referents targetable by anaphora outside the same clause (Karttunen 1976). Thus, drawing on Giannakidou (1998, 2011)’s analysis of NPIs, I argue that plural agreement with disjunctive subjects results from a deficient head within the disjunction that introduces a ‘non-deictic’ (using Giannakidou’s terminology) variable, i.e., a variable incompatible with top-level existential closure which therefore cannot be accessible outside of the semantic environment it appears in. This deficient head makes the disjunction syntactically plural, leading to the observed agreement morphology. I discuss connections with NPIs.

Location: Kaplan Hall A65