Distributive ignorance inferences with wonder and believe

A sentence like Mary wonders whether Ann, Bill or Carol broke the vase implies that Mary still consider all disjuncts possible. This inference has been referred to as a distributive ignorance inference (Roelofsen & Uegaki 2016). We present two experiments examining the distributive ignorance inferences triggered by two verbs, wonder and believe, with different types of complements and different types of quantificational subjects. The results of these experiments show that the distributive ignorance inferences triggered by the two verbs pattern very much alike. We argue that the data are best explained by an account that involves a strengthening mechanism which is sensitive to the syntactic structure of the complement of the verbs involved and optionally applies locally, as part of the semantic composition process.