A Beginner's History of Philosophy, Vol. 2: Modern Philosophy

by Herbert Ernest Cushman

The Reason and its three Ideas give what Kant calls transcendent knowledge in distinction from the transcendental knowledge of the understanding and its categories. By transcendent knowledge he means that which is beyond the limits of possible experience; while transcendental knowledge refers to knowledge about the necessary principles of experience. Kant, however, is willing to acknowledge that the Ideas of the Reason have a legitimate use. They are “regulative principles” in that, by showing what our limitations are, they also show that human knowledge is not the final goal. Their illegitimate use appears when they make a show of being true knowledge. Both science and theology will be the gainers when the Ideas are no longer used illegitimately. Kant says that he has destroyed knowledge of God and the soul “in order to make room for faith.”

The Idea of the Soul. Rational psychology had taught that the soul had direct and intuitive knowledge of itself. From the time when Descartes formulated his famous “Cogito ergo sum,” this conception of self-consciousnesshas been popular. I can have myself as the direct object of my own thought. Upon the basis of such assumed intuitive knowledge that each soul has of itself, the Rationalists had ascribed the qualities of simplicity, substantiality, spirituality, and immortality to the soul.

Kant denies that we have any such self-knowledge. If we turn back to his definition of knowledge we find it to be a synthesis of a manifold. Knowledge, to be knowledge, must (1) be based upon sensations, and on that account (2) consist only of phenomena. The soul is not phenomenal, but the deepest kind of reality. How can I have knowledge of my soul? The soul is spiritual and not phenomenal, even according to the Rationalistic philosophy. Therefore the soul is precluded from being an object of knowledge. Furthermore the Rationalists’ conception of the soul as simple and immortal would make it an impossible object of knowledge. An object of knowledge is not simple, but is the unity of a manifold. The unifying or synthesizing function is not an object to itself. Sensations are synthesized by space and time into perceptions; but space and time are not objects for the sensations. In understanding, therefore, the “I think,” which synthesizes the perceptions into judgment, cannot be an object for the understanding.

Kant points out that we must be careful to distinguish between the transcendental and the empirical ego. We have referred to this distinction already. In Kant’s criticism of knowledge he maintained that there must be postulated a “synthetic unity of apperception,” if knowledge is possible. But such an ego is only a postulate; we can have no knowledge of it nor can we saywhat it is. We know that the immediacy of experience or the sameness of knowledge from moment to moment demands this. This is the transcendental ego, a kind of universal synthetic background.

But this is different from the empirical ego, which I can know as an object of experience. The empirical ego is what I can know of myself at any time—a group of sensations, feelings, or thoughts. Now such groups change from moment to moment. My knowledge of myself consists only of my momentary, changing self. This changing self is not the immortal, simple, and identical soul of which the Rationalists have been speaking. The empirical self is complex and transitory; it is an object of knowledge, and it is not therefore the same as the immortal soul. “I think I” is impossible. “I think me” is possible. To make the “I” an object is to commit a fallacy.

The Idea of the Universe. The contradiction in reasoning about matters beyond the test of experience appears sharply with reference to problems about the world as a totality. The inherent self-contradiction of the reason attracted Kant’s attention very early with reference to the problems of infinity. Such self-contradictions were put into final shape by Kant in the Critique in the four following so-called antinomies:—

(1) The antinomy of creation. Thesis: The world must have a beginning in time and be inclosed in finite space. Antithesis: The world is eternal and infinite.

(2) The antinomy of immortality (or the simple). Thesis: The world is ultimately divisible into simple parts which cannot be further divided. Antithesis: The world is composed of parts subject to further division, and no simple thing exists in the world.

(3) The antinomy of freedom. Thesis: There is freedom; there are phenomena that cannot be accounted for by necessity. Antithesis: There is no freedom, but everything takes place entirely according to the necessary laws of nature.

(4) The antinomy of theology. Thesis: There is a necessary being either as part or as cause of the world. Antithesis: There exists neither within nor without the world an absolutely necessary being.