This article examines Wittgenstein’s criticism of Moore’s use of “know”, as he developed it in On Certainty. Arguing against much of the literature, the author claims that, by Wittgenstein’s own lights, Moore was not talking nonsense. He does so by showing, first, that the standard reading is based on the idea that hinge propositions are non-epistemic, and second, that Wittgenstein’s alleged adoption of the non-epistemic view is not adequately supported by the textual evidence. The author argues that claims to the (...) contrary depend on an undue conflation, on the part of interpreters, of Wittgenstein’s treatment of psychological avowals in Philosophical Investigations and his discussion of hinge propositions in On Certainty. Moreover, a closer look at Wittgenstein’s objections to Moore shows that Wittgenstein himself repeatedly charged Moore with a similar confusion between the status of psychological statements and the status of his common-sense truisms. (shrink)