Actuality Entailments: When the Modality is in the Presupposition

In the context of the study of modality in interaction with time, the phenomenon whereby a modalized proposition entails its non-modal counterpart has been known as an ‘actuality entailment’ since Bhatt (1999). The question that actuality entailments raise is how modal statements can be distinguished from their non-modal counterparts and how modal contributes meaning. The main idea that the paper develops is that when the actuality entailment arises, the modal contributes meaning in the presupposition. Our account disentangles the domain of quantification of the modal from its modal base. The domain of quantification is restricted by past and is reduced to the actual world by virtue of the specific type of accessibility relation used, namely, the historical accessibility relation for goal-oriented modality, in line with Belnap (1992). This predicts the entailment of actuality. The modal base itself, instead, is a non-homogeneous set of worlds that contains both p and ¬p worlds. Upon teasing apart at-issue and non-at-issue meanings, we show that the modal presupposes that ¬p was an option in the modal base. The modal sentence thus conveys that p was uncertain when seen from the time at which the modal base is determined. This paper offers new elements for comparison with implicative verbs by proposing that, like modals giving rise to the actuality entailment, they presuppose modal meaning, also in line with Baglini and Francez, 2014. Key-words: actuality entailments, modality, presupposition.1