=Has the Reason by Itself any Validity?= When Kant calls his criticism the _Critique of Pure Reason_, he uses the term “Reason” in a wide sense as the whole knowing process. In the _Dialectic_ he treats the Reason in a narrow sense, as if it were a special faculty like the perception or understanding. This is, of course, a confusing use of terms, like his use of the term “Synthesis”; but it should cause no difficulty provided the two uses are known beforehand. The term “Ideas” is also used in two senses. In this place it has a special use. While usually an idea means any thought, here it means the synthetic form of the special faculty of the reason, just as the categories are the form of the understanding, and space and time the form of sense-perception. The synthetic forms of the Reason are the three Ideas, viz., God, the soul, and the totality of the universe. What is the office of this special faculty of the Reason and its Idea-forms? They represent Kant’s way of stating the natural tendency of the human mind to get from its knowledge the greatest possible unity with the greatest possible extension. Consciousness is a synthesis which is never satisfied in being partial and incomplete. The partial syntheses of its faculties of perception and understanding do not satisfy it. Perception and understanding tell us nothing about God, about the soul, and about the totality of the universe, for these faculties are fettered to experience. Yet God, the soul, and the totality of the universe are very important matters. So the Reason leaps over the boundaries of experience, and thinks it is justified in poaching in the territory forbidden to knowledge. The Reason is not content with the partial and relational knowledge of mathematics and of physical science, but it would deal with the unrelated and the unconditioned. Indeed, we need only search our own minds to see how true Kant is to fact. We find that we ourselves are not satisfied with conditioned things, which must be explained by other conditioned things. On the contrary, we long to know the absolutely unconditioned, which alone will explain all conditions. We are forever seeking to make our synthesis complete, and to render a rational and complete account of what is nevertheless impossible to our knowledge. Now it is evident that the Ideas of the Reason are not indispensable to knowledge in the sense that the categories of the understanding and the forms of sense perception are indispensable. Cause, time, and space enter into all knowledge. Physical and mathematical laws exist as facts, and need no proof for their existence. Kant asked about them, “How are synthetic _a priori_ judgments possible?” But concerning the judgments of the Reason, he asks a different question: not _How_ are they possible, but _Are_ they possible?