Abstract

The KK thesis says (roughly) that if S knows that P, then S knows that S knows that P. Though controversial, KK may be able to neatly explain an otherwise puzzling datum: namely, that assertions of the form “P, but I don’t know if I know that P” are infelicitous. If KK is true, those assertions are unknowable, and hence guaranteed to violate a knowledge norm on assertion. For many, the fact that KK (if true) can so explain that datum is a strong consideration in its favor. This paper undermines that argument for KK. It first goes on the offensive, arguing that the more plausible “weak KK” gives a worse explanation of the datum. It then proposes an explanation which does not rely on any version of KK, but rather a "believe that you know" norm on assertion. Together, these moves undermine the linguistic argument for KK, and so significantly weaken the case for KK.