Abstract

What is the epistemological value of perceptual experience? In his recently influential paper, “The Skeptic and the Dogmatist”1, James Pryor develops a seemingly plausible answer to this question. Pryor’s answer comprises the following three theses: (F) “Our perceptual justification for beliefs about our surroundings is always defeasible – there are always possible improvements in our epistemic state which would no longer support those beliefs.” (517) (PK) “This justification that you get merely by having an experience as of p can sometimes suffice to give you knowledge that p is the case.” (520) (D) “When it perceptually seems to you as if p is the case, you have a kind of justification for believing p that does not presuppose or rest on your justification for anything else, which could be cited in argument (even an ampliative argument) for p. To have this justification for believing p, you need only have an experience that represents p as being the case. No further awareness or reflection or background beliefs are required.” (519) Let’s use the phrase “fallibilist dogmatism” to refer to the conjunction of (F), (PK), and (D).2 Pryor does not argue for either (F) or (PK) in his paper; he simply shares the widespread and plausible assumption that (F) and (PK) are both true. But the conjunction of (F) and (PK) implies that we can have knowledge on the basis of defeasible justification. And this view leads to paradox. Consider the following individually plausible but jointly incompatible statements.