ABSTRACT
This chapter examines how in the course of the second meditation, Descartes arrives at the clear and distinct idea of a thinking substance. It has always been a point of dispute at what stage of the metaphysic Descartes first concludes that he is a substance. But if Descartes can conclude, so early in the second Meditation, that he is a substance, this remains for him a conclusion to be accepted with considerable reserve. In order to discover whether or not his nature or essence consists only in thinking Descartes now proceeds to inquire more closely into what he is insofar as he is conscious of himself. The significance of the fact that Descartes states that we come to a knowledge of the mind by degrees, and as our empirical knowledge increases, is too often overlooked. It is the strain in his thinking which led finally to the treatise on the passions.
