Plurals , possibilities , and conjunctive disjunction ∗

Sentences with disjunction in the scope of a possibility modal often convey something stronger than predicted under the standard semantics for modals and disjunction, roughly paraphrasable in terms of a wide scope conjunction. You may have beer or wine, for example, is naturally understood as conveying that you may have beer and that you may have wine. This ‘puzzle of free choice permission’ (Ross, 1941) has spurred a wide array of revisions, often radical, to standard assumptions about disjunction, modality, scalar implicature, or some combination thereof. A deeper puzzle is that, while there is good evidence that the conjunctive effect is due to SCALAR IMPLICATURES, standard and well-motivated assumption about the latter predict precisely that it should not arise. In this paper I observe that plural existential quantifiers – but not singulars – pattern with possibility modals in giving rise to an analogous conjunctive effect, and that identical analytical puzzles arise. These patterns remain mysterious on otherwise plausible revisionist accounts. I explore the possibility that the pattern is in fact entirely revealing: possibility modals behave like plural existentials because they are. I suggest a unified account of the conjunctive effect as due to an ‘embedded implicature’ triggered by a DISTRIBUTIVE OPERATOR (which distributes over the parts of the plurality introduced by the plural existential/possibility modal). This implicature is a subcase of those generally triggered by universal quantifiers over disjunction. ∗This paper is based on a talk given at Sinn und Bedeutung 10, a highly condensed and simplifed version of Chapters 1 and 2 of my Ph.D Thesis (Plurality and Possibility, UCLA, 2006). The latter should thus be consulted for important details omitted or glossed over herein, and is preferable as a citation. I gratefully acknowledge the help of Philippe Schlenker and Danny Fox, and support from the following grant: ACI Systèmes Complexes en SHS (‘Implicatures, Sémantique Dynamique et Thèorie du Choix Rationnel’), CNRS/Institut Jean-Nicod, 20032005. Thanks also to Benjamin Spector, Denis Bonnay, and Emmanuel Chemla for insightful comments.