prefers to connect the aspirations and convictions that animate its deeds.
Adventuring without further preface into this field, I find that Kant's decisive contribution is the idea of a dual legislation of reason by which are marked off two distinct realms—that of science and that of morals. Each of these two realms has its own final and authoritative constitution: On one hand, there is the world of sense, the world of phenomena in space and time in which science is at home; on the other hand, is the supersensible, the noumenal world, the world of moral duty and moral freedom.
Every cultivated man is familiar with the conflict of science and religion, brute fact and ideal purpose, what is and what ought to be, necessity and freedom. In the domain of science causal dependence is sovereign; while freedom is lord of moral action. It is the proud boast of those who are Kantian in spirit that Kant discovered laws deep in the very nature of things and of human experience whose recognition puts an end forever to all possibility of conflict.
In principle, the discovery is as simple as its application is far-reaching. Both science and moral obligation exist. Analysis shows that each is based upon laws supplied by one and the same reason (of which, as he is fond of saying, reason is the legislator); but laws of such a nature that their respective jurisdictions can never compete. The material for the legislation of reason in the natural world is sense. In this sensible world of space and time, causal necessity reigns: such is the decree of reason itself. Every attempt to find freedom, to locate ideals, to draw support for man's moral aspirations in nature, is predoomed to failure. The effort of reason to do these things is contrary to the very nature of reason itself: it is self-contradictory, suicidal.
When one considers the extent in which religion has been bound up with belief in miracles, or departures from the order of nature; when one notes how support for morals has been sought in natural law; how morals have been tied up with man's natural tendencies to seek happiness and with consequences in the way of reward of virtue and punishment of vice; how history has been explained as a play of moral forces—in short, the extent to which both the grounds and the sanctions for morality have been sought within the time and space world, one realizes the scope of the revolution wrought by Kant, provided his philosophy be true. Add to this the fact that men in the past have not taken seriously the idea that every existence in space, every event in time, is connected by bonds of causal necessity with other existences and events, and consequently have had no motive for the systematic pursuit of science. How is the late appearance of science in human history to be accounted for? How are we to understand the comparatively slight influence which science still has upon the conduct of life? Men, when they have not consciously looked upon nature as a scene of caprice, have failed to bring home to themselves that nature is a scene of the legislative activity of reason in the material of sense. This fact the Kantian philosophy brings home to man once for all; it brings it home not as a pious wish, nor as a precarious hope confirmed empirically here and there by victories won by a Galileo or a Newton, but as an indubitable fact necessary to the existence of any cognitive experience at all. The reign of law in nature is the work of the same reason which proceeds empirically and haltingly to the discovery of law here and there. Thus the acceptance of the Kantian philosophy not only frees man at a single stroke from superstition, sentimentalism and moral and theological romanticism, but gives at the same stroke authorization and stimulation to the detailed efforts of man to wrest from nature her secrets of causal law. What sparse groups of men of natural science had been doing for the three preceding centuries, Kant proclaimed to be the manifestation of the essential constitution of man as a knowing being. For those who accept the Kantian philosophy, it is accordingly the magna charta of scientific work: the adequate formulation of the constitution which directs and justifies their scientific inquiries. It is a truism to say that among the Germans as nowhere else has developed a positive reverence for science. In what other land does one find in the organic law mention of Science, and read in its constitution an express provision that "Science and its teaching are free"?
But this expresses only half of Kant's work. Reason is itself supersensible. Giving law to the material of sense and so constituting nature, it is in itself above sense and nature, as a sovereign is above his subjects. The supersensible world is thus a more congenial field for its legislative activity than the physical world of space and time. But is any such field open to human experience? Has not Kant himself closed and locked the gates in his assertion that the entire operation of man's knowing powers is confined to the realm of sense in which causal necessity dominates? Yes, as far as knowledge is concerned. No, as far as moral obligation is concerned. The fact of duty, the existence of a categorical command to act thus and so, no matter what the pressure of physical surroundings or the incitation of animal inclinations, is as much a fact as the existence of knowledge of the physical world. Such a command cannot proceed from nature. What is cannot introduce man to what ought to be, and thus impose its own opposite upon him. Nature only enmeshes men in its relentless machine-like movement. The very existence of a command in man to act for the sake of what ought to be—no matter what actually is—is thus of itself final proof of the operation of supersensible reason within human experience: not, indeed, within theoretical or cognitive experience, but within moral experience.
The moral law, the law of obligation, thus proceeds from a source in man above reason. It is token of his membership as a moral being in a kingdom of absolute ends above nature. But it is also directed to something in man which is equally above nature: it appeals to and demands freedom. Reason is incapable of anything so irrational, so self-contradictory, as imposing a law of action to which no faculty of action corresponds. The freedom of the moral will is the answer to the unqualified demand of duty. It is not open to man to accept or reject this truth as he may see fit. It is a principle of reason which is involved in every exercise of reason. In denying it in name, man none the less acknowledges it in fact. Only men already sophisticated by vice who are seeking an excuse for their viciousness ever try to deny, even in words, the response which freedom makes to the voice of duty. Since, however, freedom is an absolute stranger to the natural and sensible world, man's possession of moral freedom is the final sign and seal of his membership in a supersensible world. The existence of an ideal or spiritual realm with its own laws is thus certified to by the fact of man's own citizenship within it. But, once more, this citizenship and this certification are solely moral. Scientific or intellectual warrant for it is impossible or self-contradictory, for science works by the law of causal necessity with respect to what is, ignorant of any law of freedom referring to what should be.
With the doors to the supersensible world now open, it is but a short step to religion. Of the negative traits of true religion we may be sure in advance. It will not be based upon intellectual grounds. Proofs of the existence of God, of the creation of nature, of the existence of an immaterial soul from the standpoint of knowledge are all of them impossible. They transgress the limits of knowledge, since that is confined to the sensible world of time and space. Neither will true religion be based upon historic facts such as those of Jewish history or the life of Jesus or the authority of a historic institution like a church. For all historic facts as such fall within the realm of time which is sensibly conditioned. From the points of view of natural theology and historic religions Kant was greeted by his contemporaries as the "all-shattering." Quite otherwise is it, however, as to moral proofs of religious ideas and ideals. In Kant's own words: "I have found it necessary to deny knowledge of God, freedom and immortality in order to find a place for faith"—faith being a moral act.
Then he proceeds to reinterpret in terms of the sensuous natural principle and the ideal rational principle the main doctrines of Lutheran Protestantism. The doctrines of incarnation, original sin, atonement, justification by faith and sanctification, while baseless literally and historically, are symbols of the dual nature of man, as phenomenal and noumenal. And while Kant scourges ecclesiastical religions so far as they have relied upon ceremonies and external authority, upon external rewards and punishments, yet he ascribes transitional value to them in that they have symbolized ultimate moral truths. Although dogmas are but the external vesture of inner truths, yet it may be good for us "to continue to pay reverence to the outward vesture since that has served to bring to general acceptance a doctrine which really rests upon an authority within the soul of man, and which, therefore, needs no miracle to commend it."
It is a precarious undertaking to single out some one thing in German philosophy as of typical