Informationally Redundant Utterances Alter Prior Beliefs about Event Typicality

Most theories of pragmatics and language processing predict that speakers avoid excessive informational redundancy in order to conserve unnecessary cognitive or articulatory effort. Informationally redundant utterances are, however, quite common in natural dialog. From a comprehension standpoint, it remains unclear how listeners interpret these utterances, and whether they make attempts to reconcile the ‘dips’ in informational utility with expectations of ‘appropriate’ or ‘rational’ speaker informativity. We show that informationally redundant (overinformative) utterances can trigger compensatory pragmatic inferences, which increase utterance utility in line with listener expectations. In a series of 3 studies, we look at utterances which refer to stereotyped event sequences describing common activities (scripts). When comprehenders encounter utterances describing events that can be easily inferred from prior context, they interpret them as signifying that the event conveys new, unstated information (i.e. an event otherwise assumed to be typical, such as paying the cashier when shopping, is reinterpreted as atypical in context). Further, we show that the degree to which such inferences are triggered depends on the framing of the utterance. In the absence of prosodic or discourse markers indicating the speaker’s specific intent to communicate the given information, or an utterance’s relevance to the discourse, such inferences are far less likely to arise. Overall, the results demonstrate that excessive conceptual redundancy leads to listeners revising the conversational common ground, in an effort to accommodate unexpected dips in informational utility.