Knowledge, Pragmatics, and Error

‘Know-that’, like so many natural language expressions, exhibits patterns of use that provide evidence for its context-sensitivity. A popular family of views – call it prag- matic invariantism – attempts to explain the shifty patterns by appeal to a pragmatic thesis: while the semantic meaning of ‘know-that’ is stable across all contexts of use, sentences of the form ‘S knows [doesn’t know] that p’ can be used to communicate a pragmatic content that depends on the context of use. In this paper, the author argues that pragmatic invariantism makes inaccurate predictions for a wide range of well- known use data and is committed to attributing systematic pragmatic error to ordinary speakers. But pragmatic error is unprecedented, and it is doubtful that speakers are systematically wrong about what they intend to communicate.