The body and the brain

Does self-knowledge help? A rationalist, presumably, thinks that it does: both that self-knowledge is possible and that, if gained through appropriate channels, it is desirable. Descartes notoriously claimed that, with appropriate methods of enquiry, each of his readers could become an expert on herself or himself. As well as the direct, first-person knowledge of self to which we are led in the Meditationes, we can also seek knowledge of our own bodies, and of the union of our minds and our bodies: the latter forms of self-knowledge are inevitably imperfect, but are no less important in guiding our conduct in the search after truth.