The Official Doctrine is a widely held religious description of the "internal" human spirit and the "external" human body. It is derived from Renée Descartes, a famous and respected dualist. Dualists believe that the mind and body are separate entities that are usually linked together until death. Therefore, a human being is both body and mind until the body dies. The mind exists in time and the body exists in both time and space. All matter that exists in space, including human bodies, is governed by the same mechanical laws. Conscious acts of the mind do not exist physically because they cannot be observed by others in space; therefore consciousness does not exist in the physical world, it exists in the mind. Duelists believe that people live two different lives, a private mental life and a public physical life. For example, a flower can be seen by two people at the same time thanks to a component of the body, the optic nerve, if the flower is present in space. The flower is consciously seen differently by the two people, especially if one person's optic nerve is impaired. The image of the same flower existing in the minds of the two people is different and cannot be seen by the other person through physical means. The image of the flower, as each party witnessed it, can be seen non-optically in one's own mind repeatedly through retrospection. Official doctrine states that the flower viewed retrospectively by both people is safe from illusion, confusion or doubt, because the physical component is removed. According to dualists, one person could say that the other knows the flower; because know is a word used to refer to the occurrence of a specific change in... middle of paper ......d foreign assuming that there is a distinct entity other than the body, called "l 'spirit ". Ryle provides an example of a category error made by people who are able to apply concepts in certain situations, but rely too much on abstract thoughts that leave room for error. He explains that “John Doe may be a relative, friend, enemy, or stranger of Richard Roe; but it may not be any of those things for the average taxpayer.” Conceptually, John Doe could engage in discussions about the average taxpayer, but he could never pass him on the street, as he could with Richard Roe. If John Doe recognizes the average taxpayer as a fellow citizen, he declares him to be a ghost. Therefore, relating Richard Roe's situations to the average taxpayer is not logical. Just like relating concepts from the mechanical world to the physical world is not logical.