Abstract: This chapter considers a diagnostic approach to scepticism about perceptually acquired knowledge of the external world and suggests that this approach can be pursued through a transcendental argument that belongs neither to the ambitious type (associated with P. F. Strawson) nor to the modest type (associated with Barry Stroud). The diagnosis is that this scepticism expresses an inability to make sense of the idea of direct perceptual access to objective facts about the environment. The argument aims to show that this idea must be intelligible, because it is a necessary condition for it to be intelligible that experience has a characteristic that, for the purposes of the argument, is not in doubt. The disjunctive conception of experience insists upon this idea. Crispin Wright has accused this conception of being ‘dialectically quite ineffectual’ as a response to scepticism; this charge is considered, and rejected.

Keywords: scepticism, perception, knowledge, transcendental argument, Crispin Wright, direct access,