I know how to withstand the skeptic

Abstract A prominent class of arguments for external world skepticism rely on the plausible view that knowledge is closed under logical entailment. From the fact that one does not know that one is not a handless brain in a vat it can be inferred that one does not know that one has hands, in virtue of the fact that having hands logically entails that one is not a handless brain in a vat. The complements of knowing-how ascriptions, however, are not—obviously, at least—related by logical entailment to any proposition, and therefore, they resist that skeptical argument. Even if I don’t know that I am not a brain in a vat, it does not follow that I don’t know how to, say, play a drum rudiment. Thus, knowing-how can withstand closure-based skepticism about the external world.