Descartes had not pondered the fact that, just as the sensible world, that of everyday life, is the cogitatum of sensing cogitationes, so the scientific world is the cogitatum of scientific cogitationes; and he had not noticed the circle in which he was involved when he presupposed, in his proof of the existence of God, the possibility of inferences transcending the ego, when this possibility, after all, was supposed to be established only through this proof.