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I. Fundamental Principles of the Metaphysics of Morals - Immanuel Kant, Kant’s Critique of Practical Reason and Other Works on the Theory of Ethics 
Kant’s Critique of Practical Reason and Other Works on the Theory of Ethics, trans. Thomas Kingsmill Abbott, B.D., Fellow and Tutor of Trinity College, Dublin, 4th revised ed. (London: Kongmans, Green and Co., 1889).
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Fundamental Principles of the Metaphysics of Morals
ANCIENT GREEK PHILOSOPHY was divided into three sciences: Physics, Ethics, and Logic. This division is perfectly suitable to the nature of the thing, and the only improvement that can be made in it is to add the principle on which it is based, so that we may both satisfy ourselves of its completeness, and also be able to determine correctly the necessary subdivisions.
All rational knowledge is either material or formal: the former considers some object, the latter is concerned only with the form of the understanding and of the reason itself, and with the universal laws of thought in general without distinction of its objects. Formal philosophy is called Logic. Material philosophy, however, which has to do with determinate objects and the laws to which they are subject, is again two-fold; for these laws are either laws of nature or of freedom. The science of the former is Physics, that of the latter, Ethics; they are also called natural philosophy and moral philosophy respectively.
Logic cannot have any empirical part; that is, a part in which the universal and necessary laws of thought should rest on grounds taken from experience; otherwise it would not be logic, i.e. a canon for the understanding or the reason, valid for all thought, and capable of demonstration (4). Natural and moral philosophy, on the contrary, can each have their empirical part, since the former has to determine the laws of nature as an object of experience; the latter the laws of the human will, so far as it is affected by nature: the former, however, being laws according to which everything does happen; the latter, laws according to which everything ought to happen. 1 Ethics, however, must also consider the conditions under which what ought to happen frequently does not.
We may call all philosophy empirical, so far as it is based on grounds of experience: on the other hand, that which delivers its doctrines from à priori principles alone we may call pure philosophy. When the latter is merely formal it is logic; if it is restricted to definite objects of the understanding it is metaphysic.
In this way there arises the idea of a two-fold metaphysic—a metaphysic of nature and a metaphysic of morals. Physics will thus have an empirical and also a rational part. It is the same with Ethics; but here the empirical part might have the special name of practical anthropology, the name morality being appropriated to the rational part.
All trades, arts, and handiworks have gained by division of labour, namely, when, instead of one man doing everything, each confines himself to a certain kind of work distinct from others in the treatment it requires, so as to be able to perform it with greater facility and in the greatest perfection. Where the different kinds of work are not so distinguished and divided, where everyone is a jack-of-all-trades, there manufactures remain still in the greatest barbarism. It might deserve to be considered whether pure philosophy in all its parts does not require a man specially devoted to it, and whether it would not be better for the whole business of science if those who, to please the tastes of the public, are wont to blend the rational and empirical elements together, mixed in all sorts of proportions unknown to themselves (5), and who call themselves independent thinkers, giving the name of minute philosophers to those who apply themselves to the rational part only—if these, I say, were warned not to carry on two employments together which differ widely in the treatment they demand, for each of which perhaps a special talent is required, and the combination of which in one person only produces bunglers. But I only ask here whether the nature of science does not require that we should always carefully separate the empirical from the rational part, and prefix to Physics proper (or empirical physics) a metaphysic of nature, and to practical anthropology a metaphysic of morals, which must be carefully cleared of everything empirical, so that we may know how much can be accomplished by pure reason in both cases, and from what sources it draws this its à priori teaching, and that whether the latter inquiry is conducted by all moralists (whose name is legion), or only by some who feel a calling thereto.
As my concern here is with moral philosophy, I limit the question suggested to this: Whether it is not of the utmost necessity to construct a pure moral philosophy, perfectly cleared of everything which is only empirical, and which belongs to anthropology? for that such a philosophy must be possible is evident from the common idea of duty and of the moral laws. Everyone must admit that if a law is to have moral force, i. e. to be the basis of an obligation, it must carry with it absolute necessity; that, for example, the precept, ‘Thou shalt not lie,’ is not valid for men alone, as if other rational beings had no need to observe it; and so with all the other moral laws properly so called; that, therefore, the basis of obligation must not be sought in the nature of man, or in the circumstances in the world in which he is placed, but à priori simply in the conceptions of (6) pure reason; and although any other precept which is founded on principles of mere experience may be in certain respects universal, yet in as far as it rests even in the least degree on an empirical basis, perhaps only as to a motive, such a precept, while it may be a practical rule, can never be called a moral law.
Thus not only are moral laws with their principles essentially distinguished from every other kind of practical knowledge in which there is anything empirical, but all moral philosophy rests wholly on its pure part. When applied to man, it does not borrow the least thing from the knowledge of man himself (anthropology), but gives laws à priori to him as a rational being. No doubt these laws require a judgment sharpened by experience, in order on the one hand to distinguish in what cases they are applicable, and on the other to procure for them access to the will of the man, and effectual influence on conduct; since man is acted on by so many inclinations that, though capable of the idea of a practical pure reason, he is not so easily able to make it effective in concreto in his life.
A metaphysic of morals is therefore indispensably necessary, not merely for speculative reasons, in order to investigate the sources of the practical principles which are to be found à priori in our reason, but also because morals themselves are liable to all sorts of corruption, as long as we are without that clue and supreme canon by which to estimate them correctly. For in order that an action should be morally good, it is not enough that it conform to the moral law, but it must also be done for the sake of the law, otherwise that conformity is only very contingent and uncertain; since a principle which is not moral, although it may now and then produce actions conformable to the law, will also often produce actions which contradict it (7). Now it is only in a pure philosophy that we can look for the moral law in its purity and genuineness (and, in a practical matter, this is of the utmost consequence): we must, therefore, begin with pure philosophy (metaphysic), and without it there cannot be any moral philosophy at all. That which mingles these pure principles with the empirical does not deserve the name of philosophy (for what distinguishes philosophy from common rational knowledge is, that it treats in separate sciences what the latter only comprehends confusedly); much less does it deserve that of moral philosophy, since by this confusion it even spoils the purity of morals themselves, and counteracts its own end.
Let it not be thought, however, that what is here demanded is already extant in the propædeutic prefixed by the celebrated Wolf 1 to his moral philosophy, namely, his so-called general practical philosophy, and that, therefore, we have not to strike into an entirely new field. Just because it was to be a general practical philosophy, it has not taken into consideration a will of any particular kind—say one which should be determined solely from à priori principles without any empirical motives, and which we might call a pure will, but volition in general, with all the actions and conditions which belong to it in this general signification. By this it is distinguished from a metaphysic of morals, just as general logic, which treats of the acts and canons of thought in general, is distinguished from transcendental philosophy, which treats of the particular acts and canons of pure thought, i.e. that whose cognitions are altogether à priori. For the metaphysic of morals has to examine the idea and the principles of a possible pure will, and not the acts and conditions of human volition generally, which for the most part are drawn from psychology (8). It is true that moral laws and duty are spoken of in the general practical philosophy (contrary indeed to all fitness). But this is no objection, for in this respect also the authors of that science remain true to their idea of it; they do not distinguish the motives which are prescribed as such by reason alone altogether à priori, and which are properly moral, from the empirical motives which the understanding raises to general conceptions merely by comparison of experiences; but without noticing the difference of their sources, and looking on them all as homogeneous, they consider only their greater or less amount. It is in this way they frame their notion of obligation, which, though anything but moral, is all that can be asked for in a philosophy which passes no judgment at all on the origin of all possible practical concepts, whether they are à priori, or only à posteriori.
Intending to publish hereafter a metaphysic of morals, I issue in the first instance these fundamental principles. Indeed there is properly no other foundation for it than the critical examination of a pure practical reason; just as that of metaphysics is the critical examination of the pure speculative reason, already published. But in the first place the former is not so absolutely necessary as the latter, because in moral concerns human reason can easily be brought to a high degree of correctness and completeness, even in the commonest understanding, while on the contrary in its theoretic but pure use it is wholly dialectical; and in the second place if the critique of a pure practical reason is to be complete, it must be possible at the same time to show its identity with the speculative reason in a common principle, for it can ultimately be only one and the same reason which has to be distinguished merely in its application. I could not, however, bring it to such completeness here, without introducing considerations of a wholly different kind, which would be perplexing to the reader (9). On this account I have adopted the title of Fundamental Principles of the Metaphysic of Morals, instead of that of a Critical Examination of the pure practical Reason.
But in the third place, since a metaphysic of morals, in spite of the discouraging title, is yet capable of being presented in a popular form, and one adapted to the common understanding, I find it useful to separate from it this preliminary treatise on its fundamental principles, in order that I may not hereafter have need to introduce these necessarily subtle discussions into a book of a more simple character.
The present treatise is, however, nothing more than the investigation and establishment of the supreme principle of morality, and this alone constitutes a study complete in itself, and one which ought to be kept apart from every other moral investigation. No doubt my conclusions on this weighty question, which has hitherto been very unsatisfactorily examined, would receive much light from the application of the same principle to the whole system, and would be greatly confirmed by the adequacy which it exhibits throughout; but I must forego this advantage, which indeed would be after all more gratifying than useful, since the easy applicability of a principle and its apparent adequacy give no very certain proof of its soundness, but rather inspire a certain partiality, which prevents us from examining and estimating it strictly in itself, and without regard to consequences.
I have adopted in this work the method which I think most suitable, proceeding analytically from common knowledge to the determination of its ultimate principle, and again descending synthetically from the examination of this principle and its sources to the common knowledge in which we find it employed. The division will, therefore, be as follows (10):—
transition from the common rational knowledge of morality to the philosophical.
Nothing can possibly be conceived in the world, or even out of it, which can be called good without qualification, except a Good Will. Intelligence, wit, judgment, and the other talents of the mind, however they may be named, or courage, resolution, perseverance, as qualities of temperament, are undoubtedly good and desirable in many respects; but these gifts of nature may also become extremely bad and mischievous if the will which is to make use of them, and which, therefore, constitutes what is called character, is not good. It is the same with the gifts of fortune. Power, riches, honour, even health, and the general well-being and contentment with one’s condition which is called happiness, inspire pride, and often presumption, if there is not a good will to correct the influence of these on the mind, and with this also to rectify the whole principle of acting, and adapt it to its end. The sight of a being who is not adorned with a single feature of a pure and good will, enjoying unbroken prosperity, can never give pleasure to an impartial rational spectator (12). Thus a good will appears to constitute the indispensable condition even of being worthy of happiness.
There are even some qualities which are of service to this good will itself, and may facilitate its action, yet which have no intrinsic unconditional value, but always presuppose a good will, and this qualifies the esteem that we justly have for them, and does not permit us to regard them as absolutely good. Moderation in the affections and passions, self-control and calm deliberation are not only good in many respects, but even seem to constitute part of the intrinsic worth of the person; but they are far from deserving to be called good without qualification, although they have been so unconditionally praised by the ancients. For without the principles of a good will, they may become extremely bad, and the coolness of a villain not only makes him far more dangerous, but also directly makes him more abominable in our eyes than he would have been without it.
A good will is good not because of what it performs or effects, not by its aptness for the attainment of some proposed end, but simply by virtue of the volition, that is, it is good in itself, and considered by itself is to be esteemed much higher than all that can be brought about by it in favour of any inclination, nay, even of the sum total of all inclinations. Even if it should happen that, owing to special disfavour of fortune, or the niggardly provision of a step-motherly nature, this will should wholly lack power to accomplish its purpose, if with its greatest efforts it should yet achieve nothing, and there should remain only the good will (not, to be sure, a mere wish, but the summoning of all means in our power), then, like a jewel, it would still shine by its own light, as a thing which has its whole value in itself (13). Its usefulness or fruitlessness can neither add to nor take away anything from this value. It would be, as it were, only the setting to enable us to handle it the more conveniently in common commerce, or to attract to it the attention of those who are not yet connoisseurs, but not to recommend it to true connoisseurs, or to determine its value.
There is, however, something so strange in this idea of the absolute value of the mere will, in which no account is taken of its utility, that notwithstanding the thorough assent of even common reason to the idea, yet a suspicion must arise that it may perhaps really be the product of mere high-flown fancy, and that we may have misunderstood the purpose of nature in assigning reason as the governor of our will. Therefore we will examine this idea from this point of view.
In the physical constitution of an organized being, that is, a being adapted suitably to the purposes of life, we assume it as a fundamental principle that no organ for any purpose will be found but what is also the fittest and best adapted for that purpose. Now in a being which has reason and a will, if the proper object of nature were its conservation, its welfare, in a word, its happiness, then nature would have hit upon a very bad arrangement in selecting the reason of the creature to carry out this purpose. For all the actions which the creature has to perform with a view to this purpose, and the whole rule of its conduct, would be far more surely prescribed to it by instinct, and that end would have been attained thereby much more certainly than it ever can be by reason. Should reason have been communicated to this favoured creature over and above, it must only have served it to contemplate the happy constitution of its nature (14), to admire it, to congratulate itself thereon, and to feel thankful for it to the beneficent cause, but not that it should subject its desires to that weak and delusive guidance, and meddle bunglingly with the purpose of nature. In a word, nature would have taken care that reason should not break forth into practical exercise, nor have the presumption, with its weak insight, to think out for itself the plan of happiness, and of the means of attaining it. Nature would not only have taken on herself the choice of the ends, but also of the means, and with wise foresight would have entrusted both to instinct.
And, in fact, we find that the more a cultivated reason applies itself with deliberate purpose to the enjoyment of life and happiness, so much the more does the man fail of true satisfaction. And from this circumstance there arises in many, if they are candid enough to confess it, a certain degree of misology, that is, hatred of reason, especially in the case of those who are most experienced in the use of it, because after calculating all the advantages they derive, I do not say from the invention of all the arts of common luxury, but even from the sciences (which seem to them to be after all only a luxury of the understanding), they find that they have, in fact, only brought more trouble on their shoulders, rather than gained in happiness; and they end by envying, rather than despising, the more common stamp of men who keep closer to the guidance of mere instinct, and do not allow their reason much influence on their conduct. And this we must admit, that the judgment of those who would very much lower the lofty eulogies of the advantages which reason gives us in regard to the happiness and satisfaction of life, or who would even reduce them below zero, is by no means morose or ungrateful to the goodness with which the world is governed, but that there lies at the root of these judgments the idea (15) that our existence has a different and far nobler end, for which, and not for happiness, reason is properly intended, and which must, therefore, be regarded as the supreme condition to which the private ends of man must, for the most part, be postponed.
For as reason is not competent to guide the will with certainty in regard to its objects and the satisfaction of all our wants (which it to some extent even multiplies), this being an end to which an implanted instinct would have led with much greater certainty; and since, nevertheless, reason is imparted to us as a practical faculty, i.e. as one which is to have influence on the will, therefore, admitting that nature generally in the distribution of her capacities has adapted the means to the end, its true destination must be to produce a will, not merely good as a means to something else, but good in itself, for which reason was absolutely necessary. This will then, though not indeed the sole and complete good, must be the supreme good and the condition of every other, even of the desire of happiness. Under these circumstances, there is nothing inconsistent with the wisdom of nature in the fact that the cultivation of the reason, which is requisite for the first and unconditional purpose, does in many ways interfere, at least in this life, with the attainment of the second, which is always conditional, namely, happiness. Nay, it may even reduce it to nothing, without nature thereby failing of her purpose. For reason recognises the establishment of a good will as its highest practical destination, and in attaining this purpose is capable only of a satisfaction of its own proper kind, namely, that from the attainment of an end, which end again is determined by reason only, notwithstanding that this may involve many a disappointment to the ends of inclination (16).
We have then to develop the notion of a will which deserves to be highly esteemed for itself, and is good without a view to anything further, a notion which exists already in the sound natural understanding, requiring rather to be cleared up than to be taught, and which in estimating the value of our actions always takes the first place, and constitutes the condition of all the rest. In order to do this we will take the notion of duty, which includes that of a good will, although implying certain subjective restrictions and hindrances. These, however, far from concealing it, or rendering it unrecognisable, rather bring it out by contrast, and make it shine forth so much the brighter.
I omit here all actions which are already recognised as inconsistent with duty, although they may be useful for this or that purpose, for with these the question whether they are done from duty cannot arise at all, since they even conflict with it. I also set aside those actions which really conform to duty, but to which men have no direct inclination, performing them because they are impelled thereto by some other inclination. For in this case we can readily distinguish whether the action which agrees with duty is done from duty, or from a selfish view. It is much harder to make this distinction when the action accords with duty, and the subject has besides a direct inclination to it. For example, it is always a matter of duty that a dealer should not overcharge an inexperienced purchaser, and wherever there is much commerce the prudent tradesman does not overcharge, but keeps a fixed price for everyone, so that a child buys of him as well as any other. Men are thus honestly served; but this is not enough to make us believe that the tradesman has so acted from duty and from principles of honesty: his own advantage required it; it is out of the question in this case to suppose that he might besides have a direct inclination in favour of the buyers, so that (17), as it were, from love he should give no advantage to one over another. Accordingly the action was done neither from duty nor from direct inclination, but merely with a selfish view.
On the other hand, it is a duty to maintain one’s life; and, in addition, every one has also a direct inclination to do so. But on this account the often anxious care which most men take for it has no intrinsic worth, and their maxim has no moral import. They preserve their life as duty requires, no doubt, but not because duty requires. On the other hand, if adversity and hopeless sorrow have completely taken away the relish for life; if the unfortunate one, strong in mind, indignant at his fate rather than desponding or dejected, wishes for death, and yet preserves his life without loving it—not from inclination or fear, but from duty—then his maxim has a moral worth.
To be beneficent when we can is a duty; and besides this, there are many minds so sympathetically constituted that, without any other motive of vanity or self-interest, they find a pleasure in spreading joy around them, and can take delight in the satisfaction of others so far as it is their own work. But I maintain that in such a case an action of this kind, however proper, however amiable it may be, has nevertheless no true moral worth, but is on a level with other inclinations, e. g. the inclination to honour, which, if it is happily directed to that which is in fact of public utility and accordant with duty, and consequently honourable, deserves praise and encouragement, but not esteem. For the maxim lacks the moral import, namely, that such actions be done from duty, not from inclination. Put the case that the mind of that philanthropist were clouded by sorrow of his own (18), extinguishing all sympathy with the lot of others, and that while he still has the power to benefit others in distress, he is not touched by their trouble because he is absorbed with his own; and now suppose that he tears himself out of this dead insensibility, and performs the action without any inclination to it, but simply from duty, then first has his action its genuine moral worth. Further still; if nature has put little sympathy in the heart of this or that man; if he, supposed to be an upright man, is by temperament cold and indifferent to the sufferings of others, perhaps because in respect of his own he is provided with the special gift of patience and fortitude, and supposes, or even requires, that others should have the same—and such a man would certainly not be the meanest product of nature—but if nature had not specially framed him for a philanthropist, would he not still find in himself a source from whence to give himself a far higher worth than that of a good-natured temperament could be? Unquestionably. It is just in this that the moral worth of the character is brought out which is incomparably the highest of all, namely, that he is beneficent, not from inclination, but from duty.
To secure one’s own happiness is a duty, at least indirectly; for discontent with one’s condition, under a pressure of many anxieties and amidst unsatisfied wants, might easily become a great temptation to transgression of duty. But here again, without looking to duty, all men have already the strongest and most intimate inclination to happiness, because it is just in this idea that all inclinations are combined in one total. But the precept of happiness is often of such a sort that it greatly interferes with some inclinations, and yet a man cannot form any definite and certain conception of the sum of satisfaction of all of them which is called happiness (19). It is not then to be wondered at that a single inclination, definite both as to what it promises and as to the time within which it can be gratified, is often able to overcome such a fluctuating idea, and that a gouty patient, for instance, can choose to enjoy what he likes, and to suffer what he may, since, according to his calculation, on this occasion at least, he has [only] not sacrificed the enjoyment of the present moment to a possibly mistaken expectation of a happiness which is supposed to be found in health. But even in this case, if the general desire for happiness did not influence his will, and supposing that in his particular case health was not a necessary element in this calculation, there yet remains in this, as in all other cases, this law, namely, that he should promote his happiness not from inclination but from duty, and by this would his conduct first acquire true moral worth.
It is in this manner, undoubtedly, that we are to understand those passages of Scripture also in which we are commanded to love our neighbour, even our enemy. For love, as an affection, cannot be commanded, but beneficence for duty’s sake may; even though we are not impelled to it by any inclination—nay, are even repelled by a natural and unconquerable aversion. This is practical love, and not pathological—a love which is seated in the will, and not in the propensions of sense—in principles of action and not of tender sympathy; and it is this love alone which can be commanded.
The second 1 proposition is: That an action done from duty derives its moral worth, not from the purpose which is to be attained by it, but from the maxim by which it is determined, and therefore does not depend on the realization of the object of the action, but merely on the principle of volition by which the action has taken place, without regard to any object of desire (20). It is clear from what precedes that the purposes which we may have in view in our actions, or their effects regarded as ends and springs of the will, cannot give to actions any unconditional or moral worth. In what, then, can their worth lie, if it is not to consist in the will and in reference to its expected effect? It cannot lie anywhere but in the principle of the will without regard to the ends which can be attained by the action. For the will stands between its à priori principle, which is formal, and its à posteriori spring, which is material, as between two roads, and as it must be determined by something, it follows that it must be determined by the formal principle of volition when an action is done from duty, in which case every material principle has been withdrawn from it.
The third proposition, which is a consequence of the two preceding, I would express thus: Duty is the necessity of acting from respect for the law. I may have inclination for an object as the effect of my proposed action, but I cannot have respect for it, just for this reason, that it is an effect and not an energy of will. Similarly, I cannot have respect for inclination, whether my own or another’s; I can at most, if my own, approve it; if another’s, sometimes even love it; i. e. look on it as favourable to my own interest. It is only what is connected with my will as a principle, by no means as an effect—what does not subserve my inclination, but overpowers it, or at least in case of choice excludes it from its calculation—in other words, simply the law of itself, which can be an object of respect, and hence a command. Now an action done from duty must wholly exclude the influence of inclination, and with it every object of the will, so that nothing remains which can determine the will except objectively the law, and subjectively pure respect (21) for this practical law, and consequently the maxim 1 that I should follow this law even to the thwarting of all my inclinations.
Thus the moral worth of an action does not lie in the effect expected from it, nor in any principle of action which requires to borrow its motive from this expected effect. For all these effects—agreeableness of one’s condition, and even the promotion of the happiness of others—could have been also brought about by other causes, so that for this there would have been no need of the will of a rational being; whereas it is in this alone that the supreme and unconditional good can be found. The pre-eminent good which we call moral can therefore consist in nothing else than the conception of law in itself, which certainly is only possible in a rational being, in so far as this conception, and not the expected effect, determines the will. This is a good which is already present in the person who acts accordingly, and we have not to wait for it to appear first in the result 2 (22).
But what sort of law can that be, the conception of which must determine the will, even without paying any regard to the effect expected from it, in order that this will may be called good absolutely and without qualification? As I have deprived the will of every impulse which could arise to it from obedience to any law, there remains nothing but the universal conformity of its actions to law in general, which alone is to serve the will as a principle, i. e. I am never to act otherwise than so that I could also will that my maxim should become a universal law. Here now, it is the simple conformity to law in general, without assuming any particular law applicable to certain actions, that serves the will as its principle, and must so serve it, if duty is not to be a vain delusion and a chimerical notion. The common reason of men in its practical judgments perfectly coincides with this, and always has in view the principle here suggested. Let the question be, for example: May I when in distress make a promise with the intention not to keep it? I readily distinguish here between the two significations which the question may have: Whether it is prudent (23), or whether it is right, to make a false promise. The former may undoubtedly often be the case. I see clearly indeed that it is not enough to extricate myself from a present difficulty by means of this subterfuge, but it must be well considered whether there may not hereafter spring from this lie much greater inconvenience than that from which I now free myself, and as, with all my supposed cunning, the consequences cannot be so easily foreseen but that credit once lost may be much more injurious to me than any mischief which I seek to avoid at present, it should be considered whether it would not be more prudent to act herein according to a universal maxim, and to make it a habit to promise nothing except with the intention of keeping it. But it is soon clear to me that such a maxim will still only be based on the fear of consequences. Now it is a wholly different thing to be truthful from duty, and to be so from apprehension of injurious consequences. In the first case, the very notion of the action already implies a law for me; in the second case, I must first look about elsewhere to see what results may be combined with it which would affect myself. For to deviate from the principle of duty is beyond all doubt wicked; but to be unfaithful to my maxim of prudence may often be very advantageous to me, although to abide by it is certainly safer. The shortest way, however, and an unerring one, to discover the answer to this question whether a lying promise is consistent with duty, is to ask myself, Should I be content that my maxim (to extricate myself from difficulty by a false promise) should hold good as a universal law, for myself as well as for others? and should I be able to say to myself, “Every one may make a deceitful promise when he finds himself in a difficulty from which he cannot otherwise extricate himself”? (24) Then I presently become aware that while I can will the lie, I can by no means will that lying should be a universal law. For with such a law there would be no promises at all, since it would be in vain to allege my intention in regard to my future actions to those who would not believe this allegation, or if they over-hastily did so would pay me back in my own coin. Hence my maxim, as soon as it should be made a universal law, would necessarily destory itself.
I do not, therefore, need any far-reaching penetration to discern what I have to do in order that my will may be morally good. Inexperienced in the course of the world, incapable of being prepared for all its contingencies, I only ask myself: Canst thou also will that thy maxim should be a universal law? If not, then it must be rejected, and that not because of a disadvantage accruing from it to myself or even to others, but because it cannot enter as a principle into a possible universal legislation, and reason extorts from me immediate respect for such legislation. I do not indeed as yet discern on what this respect is based (this the philosopher may inquire), but at least I understand this, that it is an estimation of the worth which far outweighs all worth of what is recommended by inclination, and that the necessity of acting from pure respect for the practical law is what constitutes duty, to which every other motive must give place, because it is the condition of a will being good in itself, and the worth of such a will is above everything.
Thus, then, without quitting the moral knowledge of common human reason, we have arrived at its principle. And although, no doubt, common men do not conceive it in such an abstract and universal form, yet they always have it really before their eyes, and use it as the standard of their decision. Here it would be easy to show how, with this compass in hand (25), men are well able to distinguish, in every case that occurs, what is good, what bad, conformably to duty or inconsistent with it, if, without in the least teaching them anything new, we only, like Socrates, direct their attention to the principle they themselves employ; and that therefore we do not need science and philosophy to know what we should do to be honest and good, yea, even wise and virtuous. Indeed we might well have conjectured beforehand that the knowledge of what every man is bound to do, and therefore also to know, would be within the reach of every man, even the commonest. 1 Here we cannot forbear admiration when we see how great an advantage the practical judgment has over the theoretical in the common understanding of men. In the latter, if common reason ventures to depart from the laws of experience and from the perceptions of the senses it falls into mere inconceivabilities and self-contradictions, at least into a chaos of uncertainty, obscurity, and instability. But in the practical sphere it is just when the common understanding excludes all sensible springs from practical laws that its power of judgment begins to show itself to advantage. It then becomes even subtle, whether it be that it chicanes with its own conscience or with other claims respecting what is to be called right, or whether it desires for its own instruction to determine honestly the worth of actions; and, in the latter case, it may even have as good a hope of hitting the mark as any philosopher whatever can promise himself. Nay, it is almost more sure of doing so, because the philosopher cannot have any other principle, while he may easily perplex his judgment by a multitude of considerations foreign to the matter, and so turn aside from the right way. Would it not therefore be wiser in moral concerns to acquiesce in the judgment of common reason (26), or at most only to call in philosophy for the purpose of rendering the system of morals more complete and intelligible, and its rules more convenient for use (especially for disputation), but not so as to draw off the common understanding from its happy simplicity, or to bring it by means of philosophy into a new path of inquiry and instruction?
Innocence is indeed a glorious thing, only, on the other hand, it is very sad that it cannot well maintain itself, and is easily seduced. On this account even wisdom—which otherwise consists more in conduct than in knowledge—yet has need of science, not in order to learn from it, but to secure for its precepts admission and permanence. Against all the commands of duty which reason represents to man as so deserving of repect, he feels in himself a powerful counterpoise in his wants and inclinations, the entire satisfaction of which he sums up under the name of happiness. Now reason issues its commands unyieldingly, without promising anything to the inclinations, and, as it were, with disregard and contempt for these claims, which are so impetuous, and at the same time so plausible, and which will not allow themselves to be suppressed by any command. Hence there arises a natural dialectic, i. e. a disposition, to argue against these strict laws of duty and to question their validity, or at least their purity and strictness; and, if possible, to make them more accordant with our wishes and inclinations, that is to say, to corrupt them at their very source, and entirely to destroy their worth—a thing which even common practical reason cannot ultimately call good.
Thus is the common reason of man compelled to go out of its sphere, and to take a step into the field of a practical philosophy, not to satisfy any speculative want (which never occurs to it as long as it is content to be mere sound reason), but even on practical grounds (27), in order to attain in it information and clear instruction respecting the source of its principle, and the correct determination of it in opposition to the maxims which are based on wants and inclinations, so that it may escape from the perplexity of opposite claims, and not run the risk of losing all genuine moral principles through the equivocation into which it easily falls. Thus, when practical reason cultivates itself, there insensibly arises in it a dialectic which forces it to seek aid in philosophy, just as happens to it in its theoretic use; and in this case, therefore, as well as in the other, it will find rest nowhere but in a thorough critical examination of our reason.
transition from popular moral philosophy to the metaphysic of morals.
If we have hitherto drawn our notion of duty from the common use of our practical reason, it is by no means to be inferred that we have treated it as an empirical notion. On the contrary, if we attend to the experience of men’s conduct, we meet frequent and, as we ourselves allow, just complaints that one cannot find a single certain example of the disposition to act from pure duty. Although many things are done in conformity with what duty prescribes, it is nevertheless always doubtful whether they are done strictly from duty, so as to have a moral worth. Hence there have, at all times, been philosophers who have altogether denied that this disposition actually exists at all in human actions, and have ascribed everything to a more or less refined self-love. Not that they have on that account questioned the soundness of the conception of morality; on the contrary, they spoke with sincere regret of the frailty and corruption of human nature, which though noble enough to take as its rule an idea so worthy of respect, is yet too weak to follow it, and employs reason, which ought to give it the law (29) only for the purpose of providing for the interest of the inclinations, whether singly or at the best in the greatest possible harmony with one another.
In fact, it is absolutely impossible to make out by experience with complete certainty a single case in which the maxim of an action, however right in itself, rested simply on moral grounds and on the conception of duty. Sometimes it happens that with the sharpest self-examination we can find nothing beside the moral principle of duty which could have been powerful enough to move us to this or that action and to so great a sacrifice; yet we cannot from this infer with certainty that it was not really some secret impulse of self-love, under the false appearance of duty, that was the actual determining cause of the will. We like then to flatter ourselves by falsely taking credit for a more noble motive; whereas in fact we can never, even by the strictest examination, get completely behind the secret springs of action; since when the question is of moral worth, it is not with the actions which we see that we are concerned, but with those inward principles of them which we do not see.
Moreover, we cannot better serve the wishes of those who ridicule all morality as a mere chimera of human imagination overstepping itself from vanity, than by conceding to them that notions of duty must be drawn only from experience (as from indolence, people are ready to think is also the case with all other notions); for this is to prepare for them a certain triumph. I am willing to admit out of love of humanity that even most of our actions are correct, but if we look closer at them we everywhere come upon the dear self which is always prominent, and it is this they have in view, and not the strict command of duty which would often require self-denial (30). Without being an enemy of virtue, a cool observer, one that does not mistake the wish for good, however lively, for its reality, may sometimes doubt whether true virtue is actually found anywhere in the world, and this especially as years increase and the judgment is partly made wiser by experience, and partly also more acute in observation. This being so, nothing can secure us from falling away altogether from our ideas of duty, or maintain in the soul a well-grounded respect for its law, but the clear conviction that although there should never have been actions which really sprang from such pure sources, yet whether this or that takes place is not at all the question; but that reason of itself, independent on all experience, ordains what ought to take place, that accordingly actions of which perhaps the world has hitherto never given an example, the feasibility even of which might be very much doubted by one who founds everything on experience, are nevertheless inflexibly commanded by reason; that, ex. gr. even though there might never yet have been a sincere friend, yet not a whit the less is pure sincerity in friendship required of every man, because, prior to all experience, this duty is involved as duty in the idea of a reason determining the will by à priori principles.
When we add further that, unless we deny that the notion of morality has any truth or reference to any possible object, we must admit that its law must be valid, not merely for men, but for all rational creatures generally, not merely under certain contingent conditions or with exceptions, but with absolute necessity, then it is clear that no experience could enable us to infer even the possibility of such apodictic laws (31). For with what right could we bring into unbounded respect as a universal precept for every rational nature that which perhaps holds only under the contingent conditions of humanity? Or how could laws of the determination of our will be regarded as laws of the determination of the will of rational beings generally, and for us only as such, if they were merely empirical, and did not take their origin wholly à priori from pure but practical reason?
Nor could anything be more fatal to morality than that we should wish to derive it from examples. For every example of it that is set before me must be first itself tested by principles of morality, whether it is worthy to serve as an original example, i. e. as a pattern, but by no means can it authoritatively furnish the conception of morality. Even the Holy One of the Gospels must first be compared with our ideal of moral perfection before we can recognise Him as such; and so He says of Himself, “Why call ye Me (whom you see) good; none is good (the model of good) but God only (whom ye do not see)?” But whence have we the conception of God as the supreme good? Simply from the idea of moral perfection, which reason frames à priori, and connects inseparably with the notion of a free-will. Imitation finds no place at all in morality, and examples serve only for encouragement, i. e. they put beyond doubt the feasibility of what the law commands, they make visible that which the practical rule expresses more generally, but they can never authorize us to set aside the true original which lies in reason, and to guide ourselves by examples.
If then there is no genuine supreme principle of morality but what must rest simply on pure reason, independent on all experience, I think it is not necessary even to put the question, whether it is good (32) to exhibit these concepts in their generality (in abstracto) as they are established à priori along with the principles belonging to them, if our knowledge is to be distinguished from the vulgar, and to be called philosophical. In our times indeed this might perhaps be necessary; for if we collected votes, whether pure rational knowledge separated from everything empirical, that is to say, metaphysic of morals, or whether popular practical philosophy is to be preferred, it is easy to guess which side would preponderate.
This descending to popular notions is certainly very commendable, if the ascent to the principles of pure reason has first taken place and been satisfactorily accomplished. This implies that we first found Ethics on Metaphysics, and then, when it is firmly established, procure a hearing for it by giving it a popular character. But it is quite absurd to try to be popular in the first inquiry, on which the soundness of the principles depends. It is not only that this proceeding can never lay claim to the very rare merit of a true philosophical popularity, since there is no art in being intelligible if one renounces all thoroughness of insight; but also it produces a disgusting medley of compiled observations and half-reasoned principles. Shallow pates enjoy this because it can be used for every-day chat, but the sagacious find in it only confusion, and being unsatisfied and unable to help themselves, they turn away their eyes, while philosophers, who see quite well through this delusion, are little listened to when they call men off for a time from this pretended popularity, in order that they might be rightfully popular after they have attained a definite insight.
We need only look at the attempts of moralists in that favourite fashion, and we shall find at one time the special constitution of human nature (33) (including, however, the idea of a rational nature generally), at one time perfection, at another happiness, here moral sense, there fear of God, a little of this, and a little of that, in marvellous mixture without its occurring to them to ask whether the principles of morality are to be sought in the knowledge of human nature at all (which we can have only from experience); and, if this is not so, if these principles are to be found altogether à priori free from everything empirical, in pure rational concepts only, and nowhere else, not even in the smallest degree; then rather to adopt the method of making this a separate inquiry, as pure practical philosophy, or (if one may use a name so decried) as metaphysic of morals, 1 to bring it by itself to completeness, and to require the public, which wishes for popular treatment, to await the issue of this undertaking.
Such a metaphysic of morals, completely isolated, not mixed with any anthropology, theology, physics, or hyperphysics, and still less with occult qualities (which we might call hypophysical), is not only an indispensable substratum of all sound theoretical knowledge of duties, but is at the same time a desideratum of the highest importance to the actual fulfilment of their precepts. For the pure conception of duty, unmixed with any foreign addition of empirical attractions (34), and, in a word, the conception of the moral law, exercises on the human heart, by way of reason alone (which first becomes aware with this that it can of itself be practical), an influence so much more powerful than all other springs 2 which may be derived from the field of experience, that in the consciousness of its worth, it despises the latter, and can by degrees become their master; whereas a mixed ethics, compounded partly of motives drawn from feelings and inclinations, and partly also of conceptions of reason, must make the mind waver between motives which cannot be brought under any principle, which lead to good only by mere accident, and very often also to evil.
From what has been said, it is clear that all moral conceptions have their seat and origin completely à priori in the reason, and that, moreover, in the commonest reason just as truly as in that which is in the highest degree speculative; that they cannot be obtained by abstraction from any empirical, and therefore merely contingent knowledge; that it is just this purity of their origin that makes them worthy to serve as our supreme practical principle (35), and that just in proportion as we add anything empirical, we detract from their genuine influence, and from the absolute value of actions; that it is not only of the greatest necessity, in a purely speculative point of view, but is also of the greatest practical importance to derive these notions and laws from pure reason, to present them pure and unmixed, and even to determine the compass of this practical or pure rational knowledge, i. e. to determine the whole faculty of pure practical reason; and, in doing so, we must not make its principles dependent on the particular nature of human reason, though in speculative philosophy this may be permitted, or may even at times be necessary; but since moral laws ought to hold good for every rational creature, we must derive them from the general concept of a rational being. In this way, although for its application to man morality has need of anthropology, yet, in the first instance, we must treat it independently as pure philosophy, i. e. as metaphysic, complete in itself (a thing which in such distinct branches of science is easily done); knowing well that unless we are in possession of this, it would not only be vain to determine the moral element of duty in right actions for purposes of speculative criticism, but it would be impossible to base morals on their genuine principles, even for common practical purposes, especially of moral instruction, so as to produce pure moral dispositions, and to engraft them on men’s minds to the promotion of the greatest possible good in the world.
But in order that in this study we may not merely advance by the natural steps from the common moral judgment (in this case very worthy of respect) to the philosophical, as has been already done, but also from a popular philosophy, which goes no further than it can reach by groping with the help of examples, to metaphysic (which does not allow itself to be checked by anything empirical (36), and as it must measure the whole extent of this kind of rational knowledge, goes as far as ideal conceptions, where even examples fail us), we must follow and clearly describe the practical faculty of reason, from the general rules of its determination to the point where the notion of duty springs from it.
Everything in nature works according to laws. Rational beings alone have the faculty of acting according to the conception of laws, that is according to principles, i. e. have a will. Since the deduction of actions from principles requires reason, the will is nothing but practical reason. If reason infallibly determines the will, then the actions of such a being which are recognised as objectively necessary are subjectively necessary also, i. e. the will is a faculty to choose that only which reason independent on inclination recognises as practically necessary, i. e. as good. But if reason of itself does not sufficiently determine the will, if the latter is subject also to subjective conditions (particular impulses) which do not always coincide with the objective conditions; in a word, if the will does not in itself completely accord with reason (which is actually the case with men), then the actions which objectively are recognised as necessary are subjectively contingent, and the determination of such a will according to objective laws is obligation, that is to say, the relation of the objective laws to a will that is not thoroughly good is conceived as the determination of the will of a rational being by principles of reason, but which the will from its nature does not of necessity follow.
The conception of an objective principle, in so far as it is obligatory for a will, is called a command (of reason), and the formula of the command is called an Imperative.
All imperatives are expressed by the word ought [or shall], and thereby indicate the relation of an objective law (37) of reason to a will, which from its subjective constitution is not necessarily determined by it (an obligation). They say that something would be good to do or to forbear, but they say it to a will which does not always do a thing because it is conceived to be good to do it. That is practically good, however, which determines the will by means of the conceptions of reason, and consequently not from subjective causes, but objectively, that is on principles which are valid for every rational being as such. It is distinguished from the pleasant, as that which influences the will only by means of sensation from merely subjective causes, valid only for the sense of this or that one, and not as a principle of reason, which holds for every one. 1
A perfectly good will would therefore be equally subject to objective laws (viz. laws of good), but could not be conceived as obliged thereby to act lawfully, because of itself from its subjective constitution it can only be determined by the conception of good (38). Therefore no imperatives hold for the Divine will, or in general for a holy will; ought is here out of place, because the volition is already of itself necessarily in unison with the law. Therefore imperatives are only formulæ to express the relation of objective laws of all volition to the subjective imperfection of the will of this or that rational being, e. g. the human will.
Now all imperatives command either hypothetically or categorically. The former represent the practical necessity of a possible action as means to something else that is willed (or at least which one might possibly will). The categorical imperative would be that which represented an action as necessary of itself without reference to another end, i.e. as objectively necessary.
Since every practical law represents a possible action as good, and on this account, for a subject who is practically determinable by reason, necessary, all imperatives are formulæ determining an action which is necessary according to the principle of a will good in some respects. If now the action is good only as a means to something else, then the imperative is hypothetical; if it is conceived as good in itself and consequently as being necessarily the principle of a will which of itself conforms to reason, then it is categorical.
Thus the imperative declares what action possible by me would be good, and presents the practical rule in relation to a will which does not forthwith perform an action simply because it is good, whether because the subject does not always know that it is good, or because, even if it know this, yet its maxims might be opposed to the objective principles of practical reason.
Accordingly the hypothetical imperative only says that the action is good for some purpose, possible or actual (39). In the first case it is a Problematical, in the second an Assertorial practical principle. The categorical imperative which declares an action to be objectively necessary in itself without reference to any purpose, i.e. without any other end, is valid as an Apodictic (practical) principle.
Whatever is possible only by the power of some rational being may also be conceived as a possible purpose of some will; and therefore the principles of action as regards the means necessary to attain some possible purpose are in fact infinitely numerous. All sciences have a practical part, consisting of problems expressing that some end is possible for us, and of imperatives directing how it may be attained. These may, therefore, be called in general imperatives of Skill. Here there is no question whether the end is rational and good, but only what one must do in order to attain it. The precepts for the physician to make his patient thoroughly healthy, and for a poisoner to ensure certain death, are of equal value in this respect, that each serves to effect its purpose perfectly. Since in early youth it cannot be known what ends are likely to occur to us in the course of life, parents seek to have their children taught a great many things, and provide for their skill in the use of means for all sorts of arbitrary ends, of none of which can they determine whether it may not perhaps hereafter be an object to their pupil, but which it is at all events possible that he might aim at; and this anxiety is so great that they commonly neglect to form and correct their judgment on the value of the things which may be chosen as ends (40).
There is one end, however, which may be assumed to be actually such to all rational beings (so far as imperatives apply to them, viz. as dependent beings), and therefore, one purpose which they not merely may have, but which we may with certainty assume that they all actually have by a natural necessity, and this is happiness. The hypothetical imperative which expresses the practical necessity of an action as means to the advancement of happiness is Assertorial. We are not to present it as necessary for an uncertain and merely possible purpose, but for a purpose which we may presuppose with certainty and à priori in every man, because it belongs to his being. Now skill in the choice of means to his own greatest well-being may be called prudence,1 in the narrowest sense. And thus the imperative which refers to the choice of means to one’s own happiness, i. e. the precept of prudence, is still always hypothetical; the action is not commanded absolutely, but only as means to another purpose.
Finally, there is an imperative which commands a certain conduct immediately, without having as its condition any other purpose to be attained by it. This imperative is Categorical. It concerns not the matter of the action, or its intended result, but its form and the principle of which it is itself a result (41); and what is essentially good in it consists in the mental disposition, let the consequence be what it may. This imperative may be called that of Morality.
There is a marked distinction also between the volitions on these three sorts of principles in the dissimilarity of the obligation of the will. In order to mark this difference more clearly, I think they would be most suitably named in their order if we said they are either rules of skill, or counsels of prudence, or commands (laws) of morality. For it is law only that involves the conception of an unconditional and objective necessity, which is consequently universally valid; and commands are laws which must be obeyed, that is, must be followed, even in opposition to inclination. Counsels, indeed, involve necessity, but one which can only hold under a contingent subjective condition, viz. they depend on whether this or that man reckons this or that as part of his happiness; the categorical imperative, on the contrary, is not limited by any condition, and as being absolutely, although practically, necessary, may be quite properly called a command. We might also call the first kind of imperatives technical (belonging to art), the second pragmatic1 (to welfare), the third moral (belonging to free conduct generally, that is, to morals).
Now arises the question, how are all these imperatives possible? This question does not seek to know how we can conceive the accomplishment of the action which the imperative ordains, but merely how we can conceive the obligation of the will (42) which the imperative expresses. No special explanation is needed to show how an imperative of skill is possible. Whoever wills the end, wills also (so far as reason decides his conduct) the means in his power which are indispensably necessary thereto. This proposition is, as regards the volition, analytical; for, in willing an object as my effect, there is already thought the causality of myself as an acting cause, that is to say, the use of the means; and the imperative educes from the conception of volition of an end the conception of actions necessary to this end. Synthetical propositions must no doubt be employed in defining the means to a proposed end; but they do not concern the principle, the act of the will, but the object and its realization. Ex. gr., that in order to bisect a line on an unerring principle I must draw from its extremities two interesecting ares; this no doubt is taught by mathematics only in synthetical propositions; but if I know that it is only by this process that the intended operation can be performed, then to say that if I fully will the operation, I also will the action required for it, is an analytical proposition; for it is one and the same thing to conceive something as an effect which I can produce in a certain way, and to conceive myself as acting in this way.
If it were only equally easy to give a definite conception of happiness, the imperatives of prudence would correspond exactly with those of skill, and would likewise be analytical. For in this case as in that, it could be said, whoever wills the end, wills also (according to the dictate of reason necessarily) the indispensable means thereto which are in his power. But, unfortunately, the notion of happiness is so indefinite that although every man wishes to attain it, yet he never can say definitely and consistently what it is that he really wishes and wills (43). The reason of this is that all the elements which belong to the notion of happiness are altogether empirical, i.e. they must be borrowed from experience, and nevertheless the idea of happiness requires an absolute whole, a maximum of welfare in my present and all future circumstances. Now it is impossible that the most clear-sighted, and at the same time most powerful being (supposed finite) should frame to himself a definite conception of what he really wills in this. Does he will riches, how much anxiety, envy, and snares might he not thereby draw upon his shoulders? Does he will knowledge and discernment, perhaps it might prove to be only an eye so much the sharper to show him so much the more fearfully the evils that are now concealed from him, and that cannot be avoided, or to impose more wants on his desires, which already give him concern enough. Would he have long life, who guarantees to him that it would not be a long misery? would he at least have health? how often has uneasiness of the body restrained from excesses into which perfect health would have allowed one to fall? and so on. In short he is unable, on any principle, to determine with certainty what would make him truly happy; because to do so he would need to be omniscient. We cannot therefore act on any definite principles to secure happiness, but only on empirical counsels, ex. gr. of regimen, frugality, courtesy, reserve, &c., which experience teaches do, on the average, most promote well-being. Hence it follows that the imperatives of prudence do not, strictly speaking, command at all, that is, they cannot present actions objectively as practically necessary; that they are rather to be regarded as counsels (consilia) than precepts (præcepta) of reason, that the problem to determine certainly and universally (44) what action would promote the happiness of a rational being is completely insoluble, and consequently no imperative respecting it is possible which should, in the strict sense, command to do what makes happy; because happiness is not an ideal of reason but of imagination, resting solely on empirical grounds, and it is vain to expect that these should define an action by which one could attain the totality of a series of consequences which is really endless. This imperative of prudence would however be an analytical proposition if we assume that the means to happiness could be certainly assigned; for it is distinguished from the imperative of skill only by this, that in the latter the end is merely possible, in the former it is given; as however both only ordain the means to that which we suppose to be willed as an end, it follows that the imperative which ordains the willing of the means to him who wills the end is in both cases analytical. Thus there is no difficulty in regard to the possibility of an imperative of this kind either.
On the other hand the question, how the imperative of morality is possible, is undoubtedly one, the only one, demanding a solution, as this is not at all hypothetical, and the objective necessity which it presents cannot rest on any hypothesis, as is the case with the hypothetical imperatives. Only here we must never leave out of consideration that we cannot make out by any example, in other words empirically, whether there is such an imperative at all; but it is rather to be feared that all those which seem to be categorical may yet be at bottom hypothetical. For instance, when the precept is: Thou shalt not promise deceitfully; and it is assumed that the necessity of this is not a mere counsel to avoid some other evil, so that it should mean: thou shalt not make a lying promise, lest if it become known thou shouldst destroy thy credit (45), but that an action of this kind must be regarded as evil in itself, so that the imperative of the prohibition is categorical; then we cannot show with certainty in any example that the will was determined merely by the law, without any other spring of action, although it may appear to be so. For it is always possible that fear of disgrace, perhaps also obscure dread of other dangers, may have a secret influence on the will. Who can prove by experience the non-existence of a cause when all that experience tells us is that we do not perceive it? But in such a case the so-called moral imperative, which as such appears to be categorical and unconditional, would in reality be only a pragmatic precept, drawing our attention to our own interests, and merely teaching us to take these into consideration.
We shall therefore have to investigate à priori the possibility of a categorical imperative, as we have not in this case the advantage of its reality being given in experience, so that [the elucidation of] its possibility should be requisite only for its explanation, not for its establishment. In the meantime it may be discerned beforehand that the categorical imperative alone has the purport of a practical law: all the rest may indeed be called principles of the will but not laws, since whatever is only necessary for the attainment of some arbitrary purpose may be considered as in itself contingent, and we can at any time be free from the precept if we give up the purpose: on the contrary, the unconditional command leaves the will no liberty to choose the opposite; consequently it alone carries with it that necessity which we require in a law.
Secondly, in the case of this categorical imperative or law of morality, the difficulty (of discerning its possibility) is a very profound one (46). It is an à priori synthetical practical proposition; 1 and as there is so much difficulty in discerning the possibility of speculative propositions of this kind, it may readily be supposed that the difficulty will be no less with the practical.
In this problem we will first inquire whether the mere conception of a categorical imperative may not perhaps supply us also with the formula of it, containing the proposition which alone can be a categorical imperative; for even if we know the tenor of such an absolute command, yet how it is possible will require further special and laborious study, which we postpone to the last section.
When I conceive a hypothetical imperative in general I do not know beforehand what it will contain until I am given the condition. But when I conceive a categorical imperative I know at once what it contains. For as the imperative contains besides the law only the necessity that the maxims 1 shall conform to this law, while the law contains no conditions restricting it, there remains nothing but the general statement that the maxim of the action should conform to a universal law (47), and it is this conformity alone that the imperative properly represents as necessary. 2
There is therefore but one categorical imperative, namely this: Act only on that maxim whereby thou canst at the same time will that it should become a universal law.
Now if all imperatives of duty can be deduced from this one imperative as from their principle, then, although it should remain undecided whether what is called duty is not merely a vain notion, yet at least we shall be able to show what we understand by it and what this notion means.
Since the universality of the law according to which effects are produced constitutes what is properly called nature in the most general sense (as to form), that is the existence of things so far as it is determined by general laws, the imperative of duty may be expressed thus: Act as if the maxim of thy action were to become by thy will a Universal Law of Nature.
We will now enumerate a few duties, adopting the usual division of them into duties to ourselves and to others, and into perfect and imperfect duties. 1 (48).
1. A man reduced to despair by a series of misfortunes feels wearied of life, but is still so far in possession of his reason that he can ask himself whether it would not be contrary to his duty to himself to take his own life. Now he inquires whether the maxim of his action could become a universal law of nature. His maxim is: From self-love I adopt it as a principle to shorten my life when its longer duration is likely to bring more evil than satisfaction. It is asked then simply whether this principle founded on self-love can become a universal law of nature. Now we see at once that a system of nature of which it should be a law to destroy life by means of the very feeling whose special nature it is to impel to the improvement of life would contradict itself, and therefore could not exist as a system of nature; hence that maxim cannot possibly exist as a universal law of nature, and consequently would be wholly inconsistent with the supreme principle of all duty. 1
2. Another finds himself forced by necessity to borrow money. He knows that he will not be able to repay it, but sees also that nothing will be lent to him, unless he promises stoutly to repay it in a definite time. He desires to make this promise, but he has still so much conscience as to ask himself: Is it not unlawful and inconsistent with duty to get out of a difficulty in this way? Suppose however that he resolves to do so, then the maxim of his action would be expressed thus: When I think myself in want of money, I will borrow money and promise to repay it, although I know that I never can do so. Now this principle of self-love or of one’s own advantage may perhaps be consistent with my whole future welfare; but the question now is, Is it right? I change then the suggestion of self-love into a universal law, and state the question thus (49): How would it be if my maxim were a universal law? Then I see at once that it could never hold as a universal law of nature, but would necessarily contradict itself. For supposing it to be a universal law that everyone when he thinks himself in a difficulty should be able to promise whatever he pleases, with the purpose of not keeping his promise, the promise itself would become impossible, as well as the end that one might have in view in it, since no one would consider that anything was promised to him, but would ridicule all such statements as vain pretences.
3. A third finds in himself a talent which with the help of some culture might make him a useful man in many respects. But he finds himself in comfortable circumstances, and prefers to indulge in pleasure rather than to take pains in enlarging and improving his happy natural capacities. He asks, however, whether his maxim of neglect of his natural gifts, besides agreeing with his inclination to indulgence, agrees also with what is called duty. He sees then that a system of nature could indeed subsist with such a universal law although men (like the South Sea islanders) should let their talents rust, and resolve to devote their lives merely to idleness, amusement, and propagation of their species—in a word, to enjoyment; but he cannot possibly will that this should be a universal law of nature, or be implanted in us as such by a natural instinct. For, as a rational being, he necessarily wills that his faculties be developed, since they serve him, and have been given him, for all sorts of possible purposes.
4. A fourth, who is in prosperity, while he sees that others have to contend with great wretchedness and that he could help them, thinks: What concern is it of mine? Let everyone be as happy (50) as heaven pleases, or as he can make himself; I will take nothing from him nor even envy him, only I do not wish to contribute anything to his welfare or to his assistance in distress! Now no doubt if such a mode of thinking were a universal law, the human race might very well subsist, and doubtless even better than in a state in which everyone talks of sympathy and good-will, or even takes care occasionally to put it into practice, but on the other side, also cheats when he can, betrays the rights of men, or otherwise violates them. But although it is possible that a universal law of nature might exist in accordance with that maxim, it is impossible to will that such a principle should have the universal validity of a law of nature. For a will which resolved this would contradict itself, inasmuch as many cases might occur in which one would have need of the love and sympathy of others, and in which, by such a law of nature, sprung from his own will, he would deprive himself of all hope of the aid he desires.
These are a few of the many actual duties, or at least what we regard as such, which obviously fall into two classes on the one principle that we have laid down. We must be able to will that a maxim of our action should be a universal law. This is the canon of the moral appreciation of the action generally. Some actions are of such a character that their maxim cannot without contradiction be even conceived as a universal law of nature, far from it being possible that we should will that it should be so. In others this intrinsic impossibility is not found, but still it is impossible to will that their maxim should be raised to the universality of a law of nature, since such a will would contradict itself. It is easily seen that the former violate strict or rigorous (inflexible) duty (51); the latter only laxer (meritorious) duty. Thus it has been completely shown by these examples how all duties depend as regards the nature of the obligation (not the object of the action) on the same principle.
If now we attend to ourselves on occasion of any transgression of duty, we shall find that we in fact do not will that our maxim should be a universal law, for that is impossible for us; on the contrary we will that the opposite should remain a universal law, only we assume the liberty of making an exception in our own favour or (just for this time only) in favour of our inclination. Consequently if we considered all cases from one and the same point of view, namely, that of reason, we should find a contradiction in our own will, namely, that a certain principle should be objectively necessary as a universal law, and yet subjectively should not be universal, but admit of exceptions. As however we at one moment regard our action from the point of view of a will wholly conformed to reason, and then again look at the same action from the point of view of a will affected by inclination, there is not really any contradiction, but an antagonism of inclination to the precept of reason, whereby the universality of the principle is changed into a mere generality, so that the practical principle of reason shall meet the maxim half way. Now, although this cannot be justified in our own impartial judgment, yet it proves that we do really recognise the validity of the categorical imperative and (with all respect for it) only allow ourselves a few exceptions, which we think unimportant and forced from us.
We have thus established at least this much, that if duty is a conception which is to have any import and real legislative authority for our actions (52), it can only be expressed in categorical, and not at all in hypothetical imperatives. We have also, which is of great importance, exhibited clearly and definitely for every practical application the content of the categorical imperative, which must contain the principle of all duty if there is such a thing at all. We have not yet, however, advanced so far as to prove à priori that there actually is such an imperative, that there is a practical law which commands absolutely of itself, and without any other impulse, and that the following of this law is duty.
With the view of attaining to this it is of extreme importance to remember that we must not allow ourselves to think of deducing the reality of this principle from the particular attributes of human nature. For duty is to be a practical, unconditional necessity of action; it must therefore hold for all rational beings (to whom an imperative can apply at all) and for this reason only be also a law for all human wills. On the contrary, whatever is deduced from the particular natural characteristics of humanity, from certain feelings and propensions, 1 nay even, if possible, from any particular tendency proper to human reason, and which need not necessarily hold for the will of every rational being; this may indeed supply us with a maxim, but not with a law; with a subjective principle on which we may have a propension and inclination to act, but not with an objective principle on which we should be enjoined to act, even though all our propensions, inclinations, and natural dispositions were opposed to it. In fact the sublimity and intrinsic dignity of the command in duty are so much the more evident, the less the subjective impulses favour it and the more they oppose it, without being able in the slighest degree to weaken the obligation of the law or to diminish its validity (53).
Here then we see philosophy brought to a critical position, since it has to be firmly fixed, notwithstanding that it has nothing to support it either in heaven or earth. Here it must show its purity as absolute dictator of its own laws, not the herald of those which are whispered to it by an implanted sense or who knows what tutelary nature. Although these may be better than nothing, yet they can never afford principles dictated by reason, which must have their source wholly à priori and thence their commanding authority, expecting everything from the supremacy of the law and the due respect for it, nothing from inclination, or else condemning the man to self-contempt and inward abhorrence.
Thus every empirical element is not only quite incapable of being an aid to the principle of morality, but is even highly prejudicial to the purity of morals, for the proper and inestimable worth of an absolutely good will consists just in this, that the principle of action is free from all influence of contingent grounds, which alone experience can furnish. We cannot too much or too often repeat our warning against this lax and even mean habit of thought which seeks for its principle amongst empirical motives and laws; for human reason in its weariness is glad to rest on this pillow, and in a dream of sweet illusions (in which, instead of Juno, it embraces a cloud) it substitutes for morality a bastard patched up from limbs of various derivation, which looks like anything one chooses to see in it; only not like virtue to one who has once beheld her in her true form. 1
(54) The question then is this: Is it a necessary law for all rational beings that they should always judge of their actions by maxims of which they can themselves will that they should serve as universal laws? If it is so, then it must be connected (altogether à priori) with the very conception of the will of a rational being generally. But in order to discover this connexion we must, however reluctantly, take a step into metaphysic, although into a domain of it which is distinct from speculative philosophy, namely, the metaphysic of morals. In a practical philosophy, where it is not the reasons of what happens that we have to ascertain, but the laws of what ought to happen, even although it never does, i. e. objective practical laws, there it is not necessary to inquire into the reasons why anything pleases or displeases, how the pleasure of mere sensation differs from taste, and whether the latter is distinct from a general satisfaction of reason; on what the feeling of pleasure or pain rests, and how from it desires and inclinations arise, and from these again maxims by the co-operation of reason: for all this belongs to an empirical psychology, which would constitute the second part of physics, if we regard physics as the philosophy of nature, so far as it is based on empirical laws. But here we are concerned with objective practical laws, and consequently with the relation of the will to itself so far as it is determined by reason alone, in which case whatever has reference to anything empirical is necessarily excluded; since if reason of itself alone determines the conduct (55) (and it is the possibility of this that we are now investigating), it must necessarily do so à priori.
The will is conceived as a faculty of determining oneself to action in accordance with the conception of certain laws. And such a faculty can be found only in rational beings. Now that which serves the will as the objective ground of its self-determination is the end, and if this is assigned by reason alone, it must hold for all rational beings. On the other hand, that which merely contains the ground of possibility of the action of which the effect is the end, this is called the means. The subjective ground of the desire is the spring, the objective ground of the volition is the motive; hence the distinction between subjective ends which rest on springs, and objective ends which depend on motives valid for every rational being. Practical principles are formal when they abstract from all subjective ends, they are material when they assume these, and therefore particular springs of action. The ends which a rational being proposes to himself at pleasure as effects of his actions (material ends) are all only relative, for it is only their relation to the particular desires of the subject that gives them their worth, which therefore cannot furnish principles universal and necessary for all rational beings and for every volition, that is to say practical laws. Hence all these relative ends can give rise only to hypothetical imperatives.
Supposing, however, that there were something whose existence has in itself an absolute worth, something which, being an end in itself, could be a source of definite laws, then in this and this alone would lie the source of a possible categorical imperative, i.e. a practical law (56).
Now I say: man and generally any rational being exists as an end in himself, not merely as a means to be arbitrarily used by this or that will, but in all his actions, whether they concern himself or other rational beings, must be always regarded at the same time as an end. All objects of the inclinations have only a conditional worth, for if the inclinations and the wants founded on them did not exist, then their object would be without value. But the inclinations themselves being sources of want, are so far from having an absolute worth for which they should be desired, that on the contrary it must be the universal wish of every rational being to be wholly free from them. Thus the worth of any object which is to be acquired by our action is always conditional. Beings whose existence depends not on our will but on nature’s, have nevertheless, if they are irrational beings, only a relative value as means, and are therefore called things; rational beings, on the contrary, are called persons, because their very nature points them out as ends in themselves, that is as something which must not be used merely as means, and so far therefore restricts freedom of action (and is an object of respect). These, therefore, are not merely subjective ends whose existence has a worth for us as an effect of our action, but objective ends, that is things whose existence is an end in itself: an end moreover for which no other can be substituted, which they should subserve merely as means, for otherwise nothing whatever would possess absolute worth; but if all worth were conditioned and therefore contingent, then there would be no supreme practical principle of reason whatever.
If then there is a supreme practical principle or, in respect of the human will, a categorical imperative, it must be one which (57), being drawn from the conception of that which is necessarily an end for every one because it is an end in itself, constitutes an objective principle of will, and can therefore serve as a universal practical law. The foundation of this principle is: rational nature exists as an end in itself. Man necessarily conceives his own existence as being so: so far then this is a subjective principle of human actions. But every other rational being regards its existence similarly, just on the same rational principle that holds for me: 1 so that it is at the same time an objective principle, from which as a supreme practical law all laws of the will must be capable of being deduced. Accordingly the practical imperative will be as follows: So act as to treat humanity, whether in thine own person or in that of any other, in every case as an end withal, never as means only. We will now inquire whether this can be practically carried out.
To abide by the previous examples:
Firstly, under the head of necessary duty to oneself: He who contemplates suicide should ask himself whether his action can be consistent with the idea of humanity as an end in itself. If he destroys himself in order to escape from painful circumstances, he uses a person merely as a mean to maintain a tolerable condition up to the end of life. But a man is not a thing, that is to say, something which can be used merely as means, but must in all his actions be always considered as an end in himself. I cannot, therefore, dispose in any way of a man in my own person so as to mutilate him, to damage or kill him (58). (It belongs to ethics proper to define this principle more precisely so as to avoid all misunderstanding, e.g. as to the amputation of the limbs in order to preserve myself; as to exposing my life to danger with a view to preserve it, &c. This question is therefore omitted here.)
Secondly, as regards necessary duties, or those of strict obligation, towards others; he who is thinking of making a lying promise to others will see at once that he would be using another man merely as a mean, without the latter containing at the same time the end in himself. For he whom I propose by such a promise to use for my own purposes cannot possibly assent to my mode of acting towards him, and therefore cannot himself contain the end of this action. This violation of the principle of humanity in other men is more obvious if we take in examples of attacks on the freedom and property of others. For then it is clear that he who transgresses the rights of men, intends to use the person of others merely as means, without considering that as rational beings they ought always to be esteemed also as ends, that is, as beings who must be capable of containing in themselves the end of the very same action. 1
Thirdly, as regards contingent (meritorious) duties to oneself; is not enough that the action does not violate humanity in our own person as an end in itself, it must also harmonise with it (59). Now there are in humanity capacities of greater perfection, which belong to the end that nature has in view in regard to humanity in ourselves as the subject: to neglect these might perhaps be consistent with the maintenance of humanity as an end in itself, but not with the advancement of this end.
Fourthly, as regards meritorious duties towards others: the natural end which all men have is their own happiness. Now humanity might indeed subsist, although no one should contribute anything to the happiness of others, provided he did not intentionally withdraw anything from it; but after all this would only harmonise negatively not positively with humanityas an end in itself, if every one does not also endeavour, as far as in him lies, to forward the ends of others. For the ends of any subject which is an end in himself, ought as far as possible to be my ends also, if that conception is to have its full effect with me.
This principle, that humanity and generally every rational nature is an end in itself (which is the supreme limiting condition of every man’s freedom of action), is not borrowed from experience, firstly, because it is universal, applying as it does to all rational beings whatever, and experience is not capable of determining anything about them; secondly, because it does not present humanity as an end to men (subjectively), that is as an object which men do of themselves actually adopt as an end; but as an objective end, which must as a law constitute the supreme limiting condition of all our subjective ends, let them be what we will; it must therefore spring from pure reason. In fact the objective principle of all practical legislation lies (according to the first principle) in the rule and its form of universality which makes it capable of being a law (say, e. g., a law of nature); but the subjective principle is in the end; now by the second principle the subject of all ends is each rational being (60), inasmuch as it is an end in itself. Hence follows the third practical principle of the will, which is the ultimate condition of its harmony with the universal practical reason, viz.: the idea of the will of every rational being as a universally legislative will.
On this principle all maxims are rejected which are inconsistent with the will being itself universal legislator. Thus the will is not subject simply to the law, but so subject that it must be regarded as itself giving the law, and on this ground only, subject to the law (of which it can regard itself as the author).
In the previous imperatives, namely, that based on the conception of the conformity of actions to general laws, as in a physical system of nature, and that based on the universal prerogative of rational beings as ends in themselves—these imperatives just because they were conceived as categorical, excluded from any share in their authority all admixture of any interest as a spring of action; they were however only assumed to be categorical, because such an assumption was necessary to explain the conception of duty. But we could not prove independently that there are practical propositions which command categorically, nor can it be proved in this section; one thing however could be done, namely, to indicate in the imperative itself by some determinate expression, that in the case of volition from duty all interest is renounced, which is the specific criterion of categorical as distinguished from hypothetical imperatives. This is done in the present (third) formula of the principle, namely, in the idea of the will of every rational being as a universally legislating will.
(61) For although a will which is subject to laws may be attached to this law by means of an interest, yet a will which is itself a supreme lawgiver so far as it is such cannot possibly depend on any interest, since a will so dependent would itself still need another law restricting the interest of its self-love by the condition that it should be valid as universal law.
Thus the principle that every human will is a will which in all its maxims gives universal laws1 , provided it be otherwise justified, would be very well adapted to be the categorical imperative, in this respect, namely, that just because of the idea of universal legislation it is not based on any interest, and therefore it alone among all possible imperatives can be unconditional. Or still better, converting the proposition, if there is a categorical imperative (i. e., a law for the will of every rational being), it can only command that everything be done from maxims of one’s will regarded as a will which could at the same time will that it should itself give universal laws, for in that case only the practical principle and the imperative which it obeys are unconditional, since they cannot be based on any interest.
Looking back now on all previous attempts to discover the principle of morality, we need not wonder why they all failed. It was seen that man was bound to laws by duty, but it was not observed that the laws to which he is subject are only those of his own giving, though at the same time they are universal (62), and that he is only bound to act in conformity with his own will; a will, however, which is designed by nature to give universal laws. For when one has conceived man only as subject to a law (no matter what), then this law required some interest, either by way of attraction or constraint, since it did not originate as a law from his own will, but this will was according to a law obliged by something else to act in a certain manner. Now by this necessary consequence all the labour spent in finding a supreme principle of duty was irrevocably lost. For men never elicited duty, but only a necessity of acting from a certain interest. Whether this interest was private or otherwise, in any case the imperative must be conditional, and could not by any means be capable of being a moral command. I will therefore call this the principle of Autonomy of the will, in contrast with every other which I accordingly reckon as Heteronomy.1
The conception of every rational being as one which must consider itself as giving in all the maxims of its will universal laws, so as to judge itself and its actions from this point of view—this conception leads to another which depends on it and is very fruitful, namely, that of a kingdom of ends.
By a kingdom I understand the union of different rational beings in a system by common laws. Now since it is by laws that ends are determined as regards their universal validity, hence, if we abstract from the personal differences of rational beings, and likewise from all the content of their private ends, we shall be able to conceive all ends combined in a systematic whole (including both rational beings as ends in themselves, and also the special ends which each may propose to himself), that is to say, we can conceive a kingdom of ends, which on the preceding principles is possible.
(63) For all rational beings come under the law that each of them must treat itself and all others never merely as means, but in every case at the same time as ends in themselves. Hence results a systematic union of rational beings by common objective laws, i.e., a kingdom which may be called a kingdom of ends, since what these laws have in view is just the relation of these beings to one another as ends and means. It is certainly only an ideal.
A rational being belongs as a member to the kingdom of ends when, although giving universal laws in it, he is also himself subject to these laws. He belongs to it as sovereign when, while giving laws, he is not subject to the will of any other.
A rational being must always regard himself as giving laws either as member or as sovereign in a kingdom of ends which is rendered possible by the freedom of will. He cannot, however, maintain the latter position merely by the maxims of his will, but only in case he is a completely independent being without wants and with unrestricted power adequate to his will.
Morality consists then in the reference of all action to the legislation which alone can render a kingdom of ends possible. This legislation must be capable of existing in every rational being, and of emanating from his will, so that the principle of this will is, never to act on any maxim which could not without contradiction be also a universal law, and accordingly always so to act that the will could at the same time regard itself as giving in its maxims universal laws. If now the maxims of rational beings are not by their own nature coincident with this objective principle, then the necessity of acting on it is called practical necessitation (64), i.e., duty. Duty does not apply to the sovereign in the kingdom of ends, but it does to every member of it and to all in the same degree.
The practical necessity of acting on this principle, i.e., duty, does not rest at all on feelings, impulses, or inclinations, but solely on the relation of rational beings to one another, a relation in which the will of a rational being must always be regarded as legislative, since otherwise it could not be conceived as an end in itself. Reason then refers every maxim of the will, regarding it as legislating universally, to every other will and also to every action towards oneself; and this not on account of any other practical motive or any future advantage, but from the idea of the dignity of a rational being, obeying no law but that which he himself also gives.
In the kingdom of ends everything has either Value or Dignity. Whatever has a value can be replaced by something else which is equivalent; whatever, on the other hand, is above all value, and therefore admits of no equivalent, has a dignity.
Whatever has reference to the general inclinations and wants of mankind has a market value; whatever, without presupposing a want, corresponds to a certain taste, that is to a satisfaction in the mere purposeless play of our faculties, has a fancy value; but that which constitutes the condition under which alone anything can be an end in itself, this has not merely a relative worth, i.e., value, but an intrinsic worth, that is dignity.
Now morality is the condition under which alone a rational being can be an end in himself, since by this alone is it possible that he should be a legislating member in the kingdom of ends. Thus morality, and humanity as capable of it, is that which alone has dignity (65). Skill and diligence in labour have a market value; wit, lively imagination, and humour, have fancy value; on the other hand, fidelity to promises, benevolence from principle (not from instinct), have an intrinsic worth. Neither nature nor art contains anything which in default of these it could put in their place, for their worth consists not in the effects which spring from them, not in the use and advantage which they secure, but in the disposition of mind, that is, the maxims of the will which are ready to manifest themselves in such actions, even though they should not have the desired effect. These actions also need no recommendation from any subjective taste or sentiment, that they may be looked on with immediate favour and satisfaction: they need no immediate propension or feeling for them; they exhibit the will that performs them as an object of an immediate respect, and nothing but reason is required to impose them on the will; not to flatter it into them, which, in the case of duties, would be a contradiction. This estimation therefore shows that the worth of such a disposition is dignity, and places it infinitely above all value, with which it cannot for a moment be brought into comparison or competition without as it were violating its sanctity.
What then is it which justifies virtue or the morally good disposition, in making such lofty claims? It is nothing less than the privilege it secures to the rational being of participating in the giving of universal laws, by which it qualifies him to be a member of a possible kingdom of ends, a privilege to which he was already destined by his own nature as being an end in himself, and on that account legislating in the kingdom of ends; free as regards all laws of physical nature, and obeying those only which he himself gives, and by which his maxims can belong to a system of universal law, to which at the same time he submits himself. For nothing has any worth except (66) what the law assigns it. Now the legislation itself which assigns the worth of everything, must for that very reason possess dignity, that is an unconditional incomparable worth, and the word respect alone supplies a becoming expression for the esteem which a rational being must have for it. Autonomy then is the basis of the dignity of human and of every rational nature.
The three modes of presenting the principle of morality that have been adduced are at bottom only so many formulæ of the very same law, and each of itself involves the other two. There is, however, a difference in them, but it is rather subjectively than objectively practical, intended namely to bring an idea of the reason nearer to intuition (by means of a certain analogy), and thereby nearer to feeling. All maxims, in fact, have—
1. A form, consisting in universality; and in this view the formula of the moral imperative is expressed thus, that the maxims must be so chosen as if they were to serve as universal laws of nature.
2. A matter,1 namely, an end, and here the formula says that the rational being, as it is an end by its own nature and therefore an end in itself, must in every maxim serve as the condition limiting all merely relative and arbitrary ends.
3. A complete characterisation of all maxims by means of that formula, namely, that all maxims ought by their own legislation to harmonise with a possible kingdom of ends as with a kingdom of nature 2 (67). There is a progress here in the order of the categories of unity of the form of the will (its universality), plurality of the matter (the objects, i.e., the ends), and totality of the system of these. In forming our moral judgment of actions it is better to proceed always on the strict method, and start from the general formula of the categorical imperative: Act according to a maxim which can at the same time make itself a universal law. If, however, we wish to gain an entrance for the moral law, it is very useful to bring one and the same action under the three specified conceptions, and thereby as far as possible to bring it nearer to intuition.
We can now end where we started at the beginning, namely, with the conception of a will unconditionally good. That will is absolutely good which cannot be evil, in other words, whose maxim, if made a universal law, could never contradict itself. This principle then is its supreme law: Act always on such a maxim as thou canst at the same time will to be a universal law; this is the sole condition under which a will can never contradict itself; and such an imperative is categorical. Since the validity of the will as a universal law for possible actions is analogous to the universal connexion of the existence of things by general laws, which is the formal notion of nature in general, the categorical imperative can also be expressed thus: Act on maxims which can at the same time have for their object themselves as universal laws of nature. Such then is the formula of an absolutely good will.
Rational nature is distinguished from the rest of nature by this, that it sets before itself an end. This end would be the matter of every good will (68). But since in the idea of a will that is absolutely good without being limited by any condition (of attaining this or that end) we must abstract wholly from every end to be effected (since this would make every will only relatively good), it follows that in this case the end must be conceived, not as an end to be effected, but as an independently existing end. Consequently it is conceived only negatively, i. e., as that which we must never act against, and which, therefore, must never be regarded merely as means, but must in every volition be esteemed as an end likewise. Now this end can be nothing but the subject of all possible ends, since this is also the subject of a possible absolutely good will; for such a will cannot without contradiction be postponed to any other object. The principle: So act in regard to every rational being (thyself and others), that he may always have place in thy maxim as an end in himself, is accordingly essentially identical with this other: Act upon a maxim which, at the same time, involves its own universal validity for every rational being. For that in using means for every end I should limit my maxim by the condition of its holding good as a law for every subject, this comes to the same thing as that the fundamental principle of all maxims of action must be that the subject of all ends, i.e., the rational being himself, be never employed merely as means, but as the supreme condition restricting the use of all means, that is in every case as an end likewise.
It follows incontestably that, to whatever laws any rational being may be subject, he being an end in himself must be able to regard himself as also legislating universally in respect of these same laws, since it is just this fitness of his maxims for universal legislation that distinguishes him as an end in himself; also it follows that this implies his dignity (prerogative) above all mere physical beings, that he must always take his (69) maxims from the point of view which regards himself, and likewise every other rational being, as lawgiving beings (on which account they are called persons). In this way a world of rational beings (mundus intelligibilis) is possible as a kingdom of ends, and this by virtue of the legislation proper to all persons as members. Therefore every rational being must so act as if he were by his maxims in every case a legislating member in the universal kingdom of ends. The formal principle of these maxims is: So act as if thy maxim were to serve likewise as the universal law (of all rational beings). A kingdom of ends is thus only possible on the analogy of a kingdom of nature, the former however only by maxims, that is self-imposed rules, the latter only by the laws of efficient causes acting under necessitation from without. Nevertheless, although the system of nature is looked upon as a machine, yet so far as it has reference to rational beings as its ends, it is given on this account the name of a kingdom of nature. Now such a kingdom of ends would be actually realised by means of maxims conforming to the canon which the categorical imperative prescribes to all rational beings, if they were universally followed. But although a rational being, even if he punctually follows this maxim himself, cannot reckon upon all others being therefore true to the same, nor expect that the kingdom of nature and its orderly arrangements shall be in harmony with him as a fitting member, so as to form a kingdom of ends to which he himself contributes, that is to say, that it shall favour his expectation of happiness, still that law: Act according to the maxims of a member of a merely possible kingdom of ends legislating in it universally, remains in its full force, inasmuch as it commands categorically. And it is just in this that the paradox lies; that the mere dignity of man as a rational creature (70), without any other end or advantage to be attained thereby, in other words, respect for a mere idea, should yet serve as an inflexible precept of the will, and that it is precisely in this independence of the maxim on all such springs of action that its sublimity consists; and it is this that makes every rational subject worthy to be a legislative member in the kingdom of ends: for otherwise he would have to be conceived only as subject to the physical law of his wants. And although we should suppose the kingdom of nature and the kingdom of ends to be united under one sovereign, so that the latter kingdom thereby ceased to be a mere idea and acquired true reality, then it would no doubt gain the accession of a strong spring, but by no means any increase of its intrinsic worth. For this sole absolute lawgiver must, notwithstanding this, be always conceived as estimating the worth of rational beings only by their disinterested behaviour, as prescribed to themselves from that idea [the dignity of man] alone. The essence of things is not altered by their external relations, and that which abstracting from these, alone constitutes the absolute worth of man, is also that by which he must be judged, whoever the judge may be, and even by the Supreme Being. Morality then is the relation of actions to the autonomy of the will, that is, to the potential universal legislation by its maxims. An action that is consistent with the autonomy of the will is permitted; one that does not agree therewith is forbidden. A will whose maxims necessarily coincide with the laws of autonomy is a holy will, good absolutely. The dependence of a will not absolutely good on the principle of autonomy (moral necessitation) is obligation. This then cannot be applied to a holy being. The objective necessity of actions from obligation is called duty.
(71) From what has just been said, it is easy to see how it happens that although the conception of duty implies subjection to the law, we yet ascribe a certain dignity and sublimity to the person who fulfils all his duties. There is not, indeed, any sublimity in him, so far as he is subject to the moral law; but inasmuch as in regard to that very law he is likewise a legislator, and on that account alone subject to it, he has sublimity. We have also shown above that neither fear nor inclination, but simply respect for the law, is the spring which can give actions a moral worth. Our own will, so far as we suppose it to act only under the condition that its maxims are potentially universal laws, this ideal will which is possible to us is the proper object of respect, and the dignity of humanity consists just in this capacity of being universally legislative, though with the condition that it is itself subject to this same legislation.
The Autonomy of the Will as the Supreme Principle of Morality.
Autonomy of the will is that property of it by which it is a law to itself (independently on any property of the objects of volition). The principle of autonomy then is: Always so to choose that the same volition shall comprehend the maxims of our choice as a universal law. We cannot prove that this practical rule is an imperative, i.e., that the will of every rational being is necessarily bound to it as a condition, by a mere analysis of the conceptions which occur in it, since it is a synthetical proposition (72); we must advance beyond the cognition of the objects to a critical examination of the subject, that is of the pure practical reason, for this synthetic proposition which commands apodictically must be capable of being cognised wholly à priori. This matter, however, does not belong to the present section. But that the principle of autonomy in question is the sole principle of morals can be readily shown by mere analysis of the conceptions of morality. For by this analysis we find that its principle must be a categorical imperative, and that what this commands is neither more nor less than this very autonomy.
Heteronomy of the Will as the Source of all spurious Principles of Morality.
If the will seeks the law which is to determine it anywhere else than in the fitness of its maxims to be universal laws of its own dictation, consequently if it goes out of itself and seeks this law in the character of any of its objects, there always results heteronomy. The will in that case does not give itself the law, but it is given by the object through its relation to the will. This relation whether it rests on inclination or on conceptions of reason only admits of hypothetical imperatives: I ought to do something because I wish for something else. On the contrary, the moral, and therefore categorical, imperative says: I ought to do so and so, even though I should not wish for anything else. Ex. gr., the former says: I ought not to lie if I would retain my reputation; the latter says: I ought not to lie although it should not bring me the least discredit. The latter therefore must so far abstract from all objects that they shall have no influence on the will, in order that practical reason (will) may not be restricted to administering an interest not belonging to it (73), but may simply show its own commanding authority as the supreme legislation. Thus, ex. gr., I ought to endeavour to promote the happiness of others, not as if its realization involved any concern of mine (whether by immediate inclination or by any satisfaction indirectly gained through reason), but simply because a maxim which excludes it cannot be comprehended as a universal law 1 in one and the same volition.