The answer is that sense perception is primarily a tool by which data about the world can be collected and then further tested with one's rational mind. For example, Descartes does not accept the existence of his body simply by seeing it, feeling it, etc. It is only when the pain is related to some problem with the body and when hunger and thirst indicate the need for food and drink that Descartes even believes that he "should not doubt that there is some truth" in the existence of his body (Descartes 56). Furthermore, Descartes is able to discern that “there is no convincing argument for supposing that there is something in fire that resembles heat, any more than for supposing that there is something that resembles pain” when talking about heat and pain apparently experienced when to be too close to the fire (Descartes 57). With this conclusion there is a very clear break with Aristotle as things do not contain within themselves all the properties that could otherwise be attributed to them only on the basis of sensorial perception. Indeed, it is in a similar way that Descartes discerns that color, as it is perceived, does not need to be present