That the distinction between body and soul belongs among the earliest advances of the human spirit on the path of its development must have struck you long ago, my dear friend, given your close familiarity with the vestiges of the most ancient eras of eastern and Greek philosophy. But even if all of these original records had been lost, this distinction would have emerged simply by a closer examination of the nature of our cognitive faculty. Right at the first dawning of reason, the thinking I, in conformity with the laws of consciousness, had to distinguish itself from every one of the representations it was thinking and consequently also from the body, particularly in so far as this body appeared among those representations. Similarly, the laws of sensibility made necessary the essential distinction between the objects of inner and of outer sense – that is, between representations in [143] us and things outside us. Now, in so far as all representations in us attach to the I as their subject, while the body belongs to the order of things outside us, the distinction that is thought in consciousness between the I and the body – between representations presented through inner sense, on the one hand, and the body that is presented through outer sense, on the other – had to be given already in intuition as well.

Thus, there was agreement very soon about the fact that the I and the body had to be two very different things.