Symposium: Descartes on perceptual cognition

Descartes, the textbooks say, divided human beings, or at least their minds, from the natural world. This is not just the consequence of metaphysical dualism, but of the concomitant indirect ‘ideas’ theory of perception. On the standard view, the soul must dimly infer the nature of the external world from the meagre, fragmentary, and often misleading input which is causally transmitted from objects through the nervous system to the brain and, ultimately, to the pineal gland. The metaphysical solipsism of the cogito, on this picture, has its psychophysiological counterpart in the way Descartes sets all goings-on in nature at such a distance from the knowing subject who is temporarily and imperfectly united with a physical body. We cannot be sure, after all, that there are human beings rather than mere automata under the hats and cloaks we see from our window.