PREFACE
If there exists on any subject a philosophy (that is, a system of rational knowledge based on concepts), then there must also be for this philosophy a system of pure rational concepts, independent of any condition of intuition, in other words, a metaphysic. It may be asked whether metaphysical elements are required also for every practical philosophy, which is the doctrine of duties, and therefore also for Ethics, in order to be able to present it as a true science (systematically), not merely as an aggregate of separate doctrines (fragmentarily). As regards pure jurisprudence, no one will question this requirement; for it concerns only what is formal in the elective will, which has to be limited in its external relations according to laws of freedom; without regarding any end which is the matter of this will. Here, therefore, deontology is a mere scientific doctrine (doctrina scientiae). *
* One who is acquainted with practical philosophy is not, therefore, a practical philosopher. The latter is he who makes the rational end the principle of his actions, while at the same time he joins with this the necessary knowledge which, as it aims at action, must not be spun out into the most subtile threads of metaphysic, unless a legal duty is in question; in which case meum and tuum must be accurately determined in the balance of justice, on the principle of equality of action and action, which requires something like mathematical proportion, but not in the case of a mere ethical duty. For in this case the question is not only to know what it is a duty to do (a thing which on account of the ends that all men naturally have can be easily decided), but the chief point is the inner principle of the will namely that the consciousness of this duty be also the spring of action, in order that we may be able to say of the man who joins to his knowledge this principle of wisdom that he is a practical philosopher.
Now in this philosophy (of ethics) it seems contrary to the idea of it that we should go back to metaphysical elements in order to make the notion of duty purified from everything empirical (from every feeling) a motive of action. For what sort of notion can we form of the mighty power and herculean strength which would be sufficient to overcome the vice-breeding inclinations, if Virtue is to borrow her "arms from the armoury of metaphysics," which is a matter of speculation that only few men can handle? Hence all ethical teaching in lecture rooms, pulpits, and popular books, when it is decked out with fragments of metaphysics, becomes ridiculous. But it is not, therefore, useless, much less ridiculous, to trace in metaphysics the first principles of ethics; for it is only as a philosopher that anyone can reach the first principles of this conception of duty, otherwise we could not look for either certainty or purity in the ethical teaching. To rely for this reason on a certain feeling which, on account of the effect expected from it, is called moral, may, perhaps, even satisfy the popular teacher, provided he desires as the criterion of a moral duty to consider the problem: "If everyone in every case made your maxim the universal law, how could this law be consistent with itself?" But if it were merely feeling that made it our duty to take this principle as a criterion, then this would not be dictated by reason, but only adopted instinctively and therefore blindly.
But in fact, whatever men imagine, no moral principle is based on any feeling, but such a principle is really nothing else than an obscurely conceived metaphysic which inheres in every man’s reasoning faculty; as the teacher will easily find who tries to catechize his pupils in the Socratic method about the imperative of duty and its application to the moral judgement of his actions. The mode of stating it need not be always metaphysical, and the language need not necessarily be scholastic, unless the pupil is to be trained to be a philosopher. But the thought must go back to the elements of metaphysics, without which we cannot expect any certainty or purity, or even motive power in ethics.
If we deviate from this principle and begin from pathological, or purely sensitive, or even moral feeling (from what is subjectively practical instead of what is objective), that is, from the matter of the will, the end, not from its form that is the law, in order from thence to determine duties; then, certainly, there are no metaphysical elements of ethics, for feeling by whatever it may be excited is always physical. But then ethical teaching, whether in schools, or lecture-rooms, etc., is corrupted in its source. For it is not a matter of indifference by what motives or means one is led to a good purpose (the obedience to duty). However disgusting, then, metaphysics may appear to those pretended philosophers who dogmatize oracularly, or even brilliantly, about the doctrine of duty, it is, nevertheless, an indispensable duty for those who oppose it to go back to its principles even in ethics, and to begin by going to school on its benches.
We may fairly wonder how, after all previous explanations of the principles of duty, so far as it is derived from pure reason, it was still possible to reduce it again to a doctrine of happiness; in such a way, however, that a certain moral happiness not resting on empirical causes was ultimately arrived at, a self-contradictory nonentity. In fact, when the thinking man has conquered the temptations to vice, and is conscious of having done his (often hard) duty, he finds himself in a state of peace and satisfaction which may well be called happiness, in which virtue is her own reward. Now, says the eudaemonist, this delight, this happiness, is the real motive of his acting virtuously. The notion of duty, says be, does not immediately determine his will; it is only by means of the happiness in prospect that he is moved to his duty. Now, on the other hand, since he can promise himself this reward of virtue only from the consciousness of having done his duty, it is clear that the latter must have preceded: that is, be must feel himself bound to do his duty before he thinks, and without thinking, that happiness will be the consequence of obedience to duty. He is thus involved in a circle in his assignment of cause and effect. He can only hope to be happy if he is conscious of his obedience to duty: and he can only be moved to obedience to duty if be foresees that he will thereby become happy. But in this reasoning there is also a contradiction. For, on the one side, he must obey his duty, without asking what effect this will have on his happiness, consequently, from a moral principle; on the other side, he can only recognize something as his duty when he can reckon on happiness which will accrue to him thereby, and consequently on a pathological principle, which is the direct opposite of the former.
I have in another place (the Berlin Monatsschrift), reduced, as I believe, to the simplest expressions the distinction between pathological and moral pleasure. The pleasure, namely, which must precede the obedience to the law in order that one may act according to the law is pathological, and the process follows the physical order of nature; that which must be preceded by the law in order that it may be felt is in the moral order. If this distinction is not observed; if eudaemonism (the principle of happiness) is adopted as the principle instead of eleutheronomy (the principle of freedom of the inner legislation), the consequence is the euthanasia (quiet death) of all morality.
The cause of these mistakes is no other than the following: Those who are accustomed only to physiological explanations will not admit into their heads the categorical imperative from which these laws dictatorially proceed, notwithstanding that they feel themselves irresistibly forced by it. Dissatisfied at not being able to explain what lies wholly beyond that sphere, namely, freedom of the elective will, elevating as is this privilege, that man has of being capable of such an idea. They are stirred up by the proud claims of speculative reason, which feels its power so strongly in the fields, just as if they were allies leagued in defence of the omnipotence of theoretical reason and roused by a general call to arms to resist that idea; and thus they are at present, and perhaps for a long time to come, though ultimately in vain, to attack the moral concept of freedom and if possible render it doubtful.