More free choice and more inclusion: An experimental investigation of free choice in nonmonotonic environments

Abstract

Disjunctions in the scope of possibility modals give rise to a conjunctive inference, generally labeled 'free choice.' A prominent approach derives free choice as a kind of scalar implicature. In this paper, we focus on the predictions of two main type of accounts within this approach, with the goal of investigating what implicature-generating algorithm best captures free choice and related data. The first is based on a standard algorithm for computing implicatures, which proceeds by negating (or 'excluding') alternatives to a sentence and adding the information so obtained to the assertion. The second proceeds by directly conjoining alternatives to the assertion (or 'including' them). This paper provides evidence that discriminates between the exclusion and the inclusion accounts. We focus on sentences involving possibility modals and disjunctions in the scope of nonmonotonic quantifiers: our key example is Exactly one girl cannot take Spanish or Calculus. We report on an inferential task experiment testing this case. We find clear evidence that the sentence has a free-choice-type reading, on which it suggests that one girl cannot take either Spanish or Calculus and all of the others can choose between the two. This is challenging for exclusion accounts, but in line with the predictions of inclusion accounts. This case constitutes, therefore, an argument for inclusion accounts.

Filtering free choice

“…Other arguments for this approach come from the well-known observation that free choice inferences are cancelable (cf. Simons 2005, Fox 2007), and from free choice readings associated with universal quantifiers (Chemla 2009, Bar-Lev & Fox 2017 and nonmonotonic quantifiers (Bassi & Bar-Lev 2016, Gotzner et al 2017). We refer the readers to the relevant sources for details.…”