Abstract
I argue that modal terms have an epistemic interpretation on which concessive knowledge attributions are semantically contradictory. This is compatible with the fallibilist view that the basis on which we know something need not entail it, but not with the view that what is known need not be epistemically certain or necessary. The apparent contradictoriness of concessive knowledge attributions is not due to mere implicature, nor to assertion updating the modal base. And it is contextually invariant. Concessive knowledge attributions contrast markedly with concessive assertions and Moorean conjunctions, whose infelicity is plausibly due to norms of assertion. I briefly explain why the strict fallibilism I recommend is compatible with our ordinary use of ‘know,’ and with our knowing much on the basis of perception. Its contextual shiftiness closely parallels our variably strict use of temporal and other invariant terms with strict application conditions.