ts. With the assurance of his existence, he is
             presented with the deeper question of what he, himself, actually is. Descartes knows that
             he is not just a body based on his doubt of the senses. Despite the fact that he feels he is
             not a body, he does believe he has properties, such as doubt, that make him a substance.
             >From this he concludes that his is an immaterial substance and that his essential property
             is self-consciousness because you can have no real proof of yourself except through your
             ...