Contextualism and closure

Abstract

Skepticism confronts us with a paradox (sometimes known as “the skeptical trilemma”), a version of which follows: (1) I know that I am working on a computer right now; (2) I know that knowing that I am working on a computer right now logically implies that I am not being deceived or manipulated in the way that skeptical hypotheses imagine. (This implication is called “closure under known logical implication”); (3) I do not or cannot know that I am not being deceived or manipulated in the way skeptical hypotheses imagine. The paradox of skepticism is that these three statements are logically incompatible. A relatively new movement in epistemology called contextualism proposes that we can accept all three of the claims in the trilemma, by recognizing that they are not all true within the same epistemic context. Briefly, contextualists claim that we can know in ordinary contexts, but cannot know that we are not being deceived or manipulated in a skeptical scenario, but the latter fact is true in a different epistemic context than the ordinary knowledge that we might have. Closure under known logical implication will remain true, but only insofar as the implications involved are alternatives that belong to the same epistemic context as the original knowledge claim. In this paper, I claim that contextualism’s account of how epistemological contexts change, together with its acceptance of closure, is implausible.