Speaker knowledge influences the comprehension of pragmatic inferences.

Inferring what speakers mean from what they say requires consideration of what they know. For instance, depending on the speaker's level of expertise, uttering Some squirrels hibernate can imply that not all squirrels hibernate, or it might imply the weaker proposition that the speaker does not know whether all squirrels hibernate. The present study examines the extent to which speaker knowledge influences implied meanings as well as the timing of any such influence. Using a self-paced presentation, participants read sentences containing some in contexts where a speaker should know whether all was true, or where the speaker merely might know whether all was true. This knowledge manipulation was found to have immediate and reliable effects on the type of inference that was drawn. In contrast, knowledge played no role when the same meanings were conveyed literally. This work thus demonstrates that perceivers consider the speaker's knowledge state incrementally to establish the speaker's communicative goals.