Abstract
Examining the effectiveness of the Kant’s Refutation of Idealism as a critique of a Cartesian account of consciousness, I argue that Kant's reasoning turns on the insight that self-knowledge presupposes independent temporal determination of the self. This insight bears an intriguing resemblance to claims about meaning and justification that appear in Wittgenstein's later work. Much as Wittgenstein rules out the possibility of a private language, whose meanings derive from acts of inner ostensive definition, on the ground that language requires an independent standard of meaning, so Kant shows that there must be objects in space and time outside me because they constitute the only independent standard of temporality, relative to which I can be conscious of my own existence as determined in time. But Kant only partially anticipates Wittgenstein because the former does not fully appreciate the linguistic nature of judgment.