The central thesis of robust virtue epistemology (RVE) is that the difference between knowledge and mere true belief is that knowledge involves success that is attributable to a subject's abilities. An influential objection to this approach is that RVE delivers the wrong verdicts in cases of environmental luck. Critics of RVE argue that the view needs to be supplemented with modal anti-luck condition. This particular criticism rests on a number of mistakes about the nature of ability that I shall try (...) to rectify here. (shrink)

Fred Dretske notoriously claimed that knowledge closure sometimes fails. Crispin Wright agrees that warrant does not transmit in the relevant cases, but only because the agent must already be warranted in believing the conclusion in order to acquire her warrant for the premise. So the agent ends up being warranted in believing, and so knowing, the conclusion in those cases too: closure is preserved. Wright's argument requires that the conclusion's having to be warranted beforehand explains transmission failure. I argue that (...) it doesn't, and that the correct explanation does not imply that the agent will end up warranted in believing the conclusion when transmission fails. Those who agree that transmission does fail in those cases, therefore, might as well follow Dretske in denying knowledge closure too. (shrink)