But though it is by no means the task of apologetics to build up these ideas directly from a study of things, it is of no little importance to inquire whether religion possesses in these convictions only postulates of faith, for which it must laboriously and forcibly make a place in the face of knowledge, or whether a thorough and self-critical knowledge does not rather confirm them, and show us, within the world of knowledge itself, unmistakable signs that it cannot be the true, full reality, but points to something beyond itself. To study this question thoroughly would involve setting forth a special theory of knowledge and existence. This cannot be attempted here. But Kant’s great doctrine of the “Antinomy of Reason” has for all time broken up for us the narrowness of the naturalistic way of thinking. Every one who has felt cramped by the narrow limits in which reality was confined by a purely mundane outlook must have experienced the liberating influence of the Kantian Antinomy if he has thought over it carefully. The thick curtain which separates being from appearance seems to be torn away, or at any rate to reveal itself as a curtain. Kant shows that, if we were to take this world as it lies before us for the true reality, we should land in inextricable contradictions. These contradictions show that the true world itself cannot coincide with our thought and comprehension, for in being itself there can be no contradictions. Otherwise it would not exist. The ancient problems of philosophy, from the time of the Eleatic school onwards, find here their adequate formulation. Kant’s disciple, Fries, has carried the matter further, and has attempted to develop what for Kant still remained a sort of embarrassment of reason to more precise pronouncements as to the relation of true being to its manifestation, The Antimony of Our Conception of Time.