Content Nouns and the Semantics of Question-Embedding

This article proposes that RESPONSIVE PREDICATES-predicates that embed both interrogatives and declaratives, such as know-select for questions (modeled as sets of propositions) rather than propositions. Declarative complements denote singleton proposition-sets, meaning that declarative-embedding is a special ('trivialized') case of question-embedding. This analysis is in contrast to the more standard analysis of responsive predicates that treats them as proposition-taking items and reduces embedded questions to propositions (Groenendijk & Stokhof 1984; Lahiri 2002). The argument is based on the semantic contrast between responsive predicates and predicates that only embed declaratives (e. g., believe), when they take DP complements headed by content nouns (Vendler 1972), as in John knows the rumor that Mary left vs. John believes the rumor that Mary left. Under the common assumption that responsive predicates are proposition-taking, any plausible predictive account of the entailment from John believes the rumor that Mary left to John believes that Mary left would run into an incorrect prediction that John knows the rumor that Mary left would also entail John knows that Mary left. On the other hand, if responsive predicates are question-taking, the contrast can be captured given an inventory of type-shifters that map entities to propositions and questions. It is also argued that the proposed analysis enables a natural semantic account of the selectional restrictions of attitude predicates: believe-type predicates select for propositions, know-type predicates select for questions, and ask/wondertype predicates select for non-singleton questions.