 But how could ideas deriving from the subjective character of experience justify a substantive metaphysical conclusion about the existence of a real self? On one plausible line of reply, Descartes does not yet intend to be establishing the metaphysical result; rather, the initial intended result is merely epistemic, but not (yet) fully justified. This line of interpretation does, of course, imply that the cogito does not initially count as perfect knowledge – an issue to which we now turn.