Catherine Elgin proposes a novel principle for identifying epistemic virtue. Based loosely on Kant's Categorical Imperative, it identifies autonomy as our fundamental epistemic responsibility, and defines the epistemic virtues as those traits of character needed to exercise epistemic autonomy. I argue that Elgin's principle fails as a criterion of epistemic virtue because the instrumental conception of autonomy on which it relies leads to an untenable relativism. Despite this, I suggest that autonomy may yet furnish a plausible criterion for epistemic virtue, provided we construe autonomy as Kant does, as grounded in categorical rather than instrumental reason. (Contains 12 notes.)