It is plausible to suppose that, if knowing requires believing on the basis of evidence that entails what is believed, we have hardly any knowledge at all. Hence the near-universal acceptance of fallibilism (Cohen 1988, 91). Hence too the significance of ‘concessive knowledge attributions’ (CKAs) (Rysiew 2001)—i.e., sentences of the form ‘S knows that p, but it is possible that q’ (where q entails not-p). To many, utterances of such sentences sound very odd: