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.

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, being drawn from the conception of that which is necessarily an end for everyone 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: * 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.



* This proposition is here stated as a postulate. The ground of it will be found in the concluding section.



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. (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, etc. 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 a 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. *



* Let it not be thought that the common "quod tibi non vis fieri, etc." could serve here as the rule or principle. For it is only a deduction from the former, though with several limitations; it cannot be a universal law, for it does not contain the principle of duties to oneself, nor of the duties of benevolence to others (for many a one would gladly consent that others should not benefit him, provided only that he might be excused from showing benevolence to them), nor finally that of duties of strict obligation to one another, for on this principle the criminal might argue against the judge who punishes him, and so on.



Thirdly, as regards contingent (meritorious) duties to oneself: It is not enough that the action does not violate humanity in our own person as an end in itself, it must also harmonize with it. 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 harmonize negatively not positively with humanity as 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, 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 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.

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 laws, * 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 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.



* I may be excused from adducing examples to elucidate this principle, as those which have already been used to elucidate the categorical imperative and its formula would all serve for the like purpose here.



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, 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.

The conception of the will 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.

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 being 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, 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. 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 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 formulae 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, 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 characterization of all maxims by means of that formula, namely, that all maxims ought by their own legislation to harmonize with a possible kingdom of ends as with a kingdom of nature. * 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 judgement 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.



* Teleology considers nature as a kingdom of ends; ethics regards a possible kingdom of ends as a kingdom nature. In the first case, the kingdom of ends is a theoretical idea, adopted to explain what actually is. In the latter it is a practical idea, adopted to bring about that which is not yet, but which can be realized by our conduct, namely, if it conforms to this idea.



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. 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 maxims from the point of view which regards himself and, likewise, every other rational being as law-giving 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 realized 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, 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 relation of actions will, that is, to the autonomy of 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.

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 of 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; 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 apodeictically must be capable of being cognized wholly a 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." E.g., 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, but may simply show its own commanding authority as the supreme legislation. Thus, e.g., 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 in one and the same volition.



Classification of all Principles of Morality which can be

founded on the Conception of Heteronomy



Here as elsewhere human reason in its pure use, so long as it was not critically examined, has first tried all possible wrong ways before it succeeded in finding the one true way.

All principles which can be taken from this point of view are either empirical or rational. The former, drawn from the principle of happiness, are built on physical or moral feelings; the latter, drawn from the principle of perfection, are built either on the rational conception of perfection as a possible effect, or on that of an independent perfection (the will of God) as the determining cause of our will.

Empirical principles are wholly incapable of serving as a foundation for moral laws. For the universality with which these should hold for all rational beings without distinction, the unconditional practical necessity which is thereby imposed on them, is lost when their foundation is taken from the particular constitution of human nature, or the accidental circumstances in which it is placed. The principle of private happiness, however, is the most objectionable, not merely because it is false, and experience contradicts the supposition that prosperity is always proportioned to good conduct, nor yet merely because it contributes nothing to the establishment of morality- since it is quite a different thing to make a prosperous man and a good man, or to make one prudent and sharp-sighted for his own interests and to make him virtuous- but because the springs it provides for morality are such as rather undermine it and destroy its sublimity, since they put the motives to virtue and to vice in the same class and only teach us to make a better calculation, the specific difference between virtue and vice being entirely extinguished. On the other hand, as to moral feeling, this supposed special sense, * the appeal to it is indeed superficial when those who cannot think believe that feeling will help them out, even in what concerns general laws: and besides, feelings, which naturally differ infinitely in degree, cannot furnish a uniform standard of good and evil, nor has anyone a right to form judgements for others by his own feelings: nevertheless this moral feeling is nearer to morality and its dignity in this respect, that it pays virtue the honour of ascribing to her immediately the satisfaction and esteem we have for her and does not, as it were, tell her to her face that we are not attached to her by her beauty but by profit.



* I class the principle of moral feeling under that of happiness, because every empirical interest promises to contribute to our well-being by the agreeableness that a thing affords, whether it be immediately and without a view to profit, or whether profit be regarded. We must likewise, with Hutcheson, class the principle of sympathy with the happiness of others under his assumed moral sense.



Amongst the rational principles of morality, the ontological conception of perfection, notwithstanding its defects, is better than the theological conception which derives morality from a Divine absolutely perfect will. The former is, no doubt, empty and indefinite and consequently useless for finding in the boundless field of possible reality the greatest amount suitable for us; moreover, in attempting to distinguish specifically the reality of which we are now speaking from every other, it inevitably tends to turn in a circle and cannot avoid tacitly presupposing the morality which it is to explain; it is nevertheless preferable to the theological view, first, because we have no intuition of the divine perfection and can only deduce it from our own conceptions, the most important of which is that of morality, and our explanation would thus be involved in a gross circle; and, in the next place, if we avoid this, the only notion of the Divine will remaining to us is a conception made up of the attributes of desire of glory and dominion, combined with the awful conceptions of might and vengeance, and any system of morals erected on this foundation would be directly opposed to morality.

However, if I had to choose between the notion of the moral sense and that of perfection in general (two systems which at least do not weaken morality, although they are totally incapable of serving as its foundation), then I should decide for the latter, because it at least withdraws the decision of the question from the sensibility and brings it to the court of pure reason; and although even here it decides nothing, it at all events preserves the indefinite idea (of a will good in itself free from corruption, until it shall be more precisely defined.

For the rest I think I may be excused here from a detailed refutation of all these doctrines; that would only be superfluous labour, since it is so easy, and is probably so well seen even by those whose office requires them to decide for one of these theories (because their hearers would not tolerate suspension of judgement). But what interests us more here is to know that the prime foundation of morality laid down by all these principles is nothing but heteronomy of the will, and for this reason they must necessarily miss their aim.

In every case where an object of the will has to be supposed, in order that the rule may be prescribed which is to determine the will, there the rule is simply heteronomy; the imperative is conditional, namely, if or because one wishes for this object, one should act so and so: hence it can never command morally, that is, categorically. Whether the object determines the will by means of inclination, as in the principle of private happiness, or by means of reason directed to objects of our possible volition generally, as in the principle of perfection, in either case the will never determines itself immediately by the conception of the action, but only by the influence which the foreseen effect of the action has on the will; I ought to do something, on this account, because I wish for something else; and here there must be yet another law assumed in me as its subject, by which I necessarily will this other thing, and this law again requires an imperative to restrict this maxim. For the influence which the conception of an object within the reach of our faculties can exercise on the will of the subject, in consequence of its natural properties, depends on the nature of the subject, either the sensibility (inclination and taste), or the understanding and reason, the employment of which is by the peculiar constitution of their nature attended with satisfaction. It follows that the law would be, properly speaking, given by nature, and, as such, it must be known and proved by experience and would consequently be contingent and therefore incapable of being an apodeictic practical rule, such as the moral rule must be. Not only so, but it is inevitably only heteronomy; the will does not give itself the law, but is given by a foreign impulse by means of a particular natural constitution of the subject adapted to receive it. An absolutely good will, then, the principle of which must be a categorical imperative, will be indeterminate as regards all objects and will contain merely the form of volition generally, and that as autonomy, that is to say, the capability of the maxims of every good will to make themselves a universal law, is itself the only law which the will of every rational being imposes on itself, without needing to assume any spring or interest as a foundation.

How such a synthetical practical a priori proposition is possible, and why it is necessary, is a problem whose solution does not lie within the bounds of the metaphysic of morals; and we have not here affirmed its truth, much less professed to have a proof of it in our power. We simply showed by the development of the universally received notion of morality that an autonomy of the will is inevitably connected with it, or rather is its foundation. Whoever then holds morality to be anything real, and not a chimerical idea without any truth, must likewise admit the principle of it that is here assigned. This section then, like the first, was merely analytical. Now to prove that morality is no creation of the brain, which it cannot be if the categorical imperative and with it the autonomy of the will is true, and as an a priori principle absolutely necessary, this supposes the possibility of a synthetic use of pure practical reason, which however we cannot venture on without first giving a critical examination of this faculty of reason. In the concluding section we shall give the principal outlines of this critical examination as far as is sufficient for our purpose.

SEC_3

THIRD SECTION



TRANSITION FROM THE METAPHYSIC OF MORALS TO THE

CRITIQUE OF PURE PRACTICAL REASON



The Concept of Freedom is the Key that explains the Autonomy of the Will



The will is a kind of causality belonging to living beings in so far as they are rational, and freedom would be this property of such causality that it can be efficient, independently of foreign causes determining it; just as physical necessity is the property that the causality of all irrational beings has of being determined to activity by the influence of foreign causes.

The preceding definition of freedom is negative and therefore unfruitful for the discovery of its essence, but it leads to a positive conception which is so much the more full and fruitful.

Since the conception of causality involves that of laws, according to which, by something that we call cause, something else, namely the effect, must be produced; hence, although freedom is not a property of the will depending on physical laws, yet it is not for that reason lawless; on the contrary it must be a causality acting according to immutable laws, but of a peculiar kind; otherwise a free will would be an absurdity. Physical necessity is a heteronomy of the efficient causes, for every effect is possible only according to this law, that something else determines the efficient cause to exert its causality. What else then can freedom of the will be but autonomy, that is, the property of the will to be a law to itself? But the proposition: "The will is in every action a law to itself," only expresses the principle: "To act on no other maxim than that which can also have as an object itself as a universal law." Now this is precisely the formula of the categorical imperative and is the principle of morality, so that a free will and a will subject to moral laws are one and the same.

On the hypothesis, then, of freedom of the will, morality together with its principle follows from it by mere analysis of the conception. However, the latter is a synthetic proposition; viz., an absolutely good will is that whose maxim can always include itself regarded as a universal law; for this property of its maxim can never be discovered by analysing the conception of an absolutely good will. Now such synthetic propositions are only possible in this way: that the two cognitions are connected together by their union with a third in which they are both to be found. The positive concept of freedom furnishes this third cognition, which cannot, as with physical causes, be the nature of the sensible world (in the concept of which we find conjoined the concept of something in relation as cause to something else as effect). We cannot now at once show what this third is to which freedom points us and of which we have an idea a priori, nor can we make intelligible how the concept of freedom is shown to be legitimate from principles of pure practical reason and with it the possibility of a categorical imperative; but some further preparation is required.



Freedom must be presupposed as a Property of the Will

of all Rational Beings



It is not enough to predicate freedom of our own will, from Whatever reason, if we have not sufficient grounds for predicating the same of all rational beings. For as morality serves as a law for us only because we are rational beings, it must also hold for all rational beings; and as it must be deduced simply from the property of freedom, it must be shown that freedom also is a property of all rational beings. It is not enough, then, to prove it from certain supposed experiences of human nature (which indeed is quite impossible, and it can only be shown a priori), but we must show that it belongs to the activity of all rational beings endowed with a will. Now I say every being that cannot act except under the idea of freedom is just for that reason in a practical point of view really free, that is to say, all laws which are inseparably connected with freedom have the same force for him as if his will had been shown to be free in itself by a proof theoretically conclusive. * Now I affirm that we must attribute to every rational being which has a will that it has also the idea of freedom and acts entirely under this idea. For in such a being we conceive a reason that is practical, that is, has causality in reference to its objects. Now we cannot possibly conceive a reason consciously receiving a bias from any other quarter with respect to its judgements, for then the subject would ascribe the determination of its judgement not to its own reason, but to an impulse. It must regard itself as the author of its principles independent of foreign influences. Consequently as practical reason or as the will of a rational being it must regard itself as free, that is to say, the will of such a being cannot be a will of its own except under the idea of freedom. This idea must therefore in a practical point of view be ascribed to every rational being.



* I adopt this method of assuming freedom merely as an idea which rational beings suppose in their actions, in order to avoid the necessity of proving it in its theoretical aspect also. The former is sufficient for my purpose; for even though the speculative proof should not be made out, yet a being that cannot act except with the idea of freedom is bound by the same laws that would oblige a being who was actually free. Thus we can escape here from the onus which presses on the theory.



Of the Interest attaching to the Ideas of Morality



We have finally reduced the definite conception of morality to the idea of freedom. This latter, however, we could not prove to be actually a property of ourselves or of human nature; only we saw that it must be presupposed if we would conceive a being as rational and conscious of its causality in respect of its actions, i.e., as endowed with a will; and so we find that on just the same grounds we must ascribe to every being endowed with reason and will this attribute of determining itself to action under the idea of its freedom.

Now it resulted also from the presupposition of these ideas that we became aware of a law that the subjective principles of action, i.e., maxims, must always be so assumed that they can also hold as objective, that is, universal principles, and so serve as universal laws of our own dictation. But why then should I subject myself to this principle and that simply as a rational being, thus also subjecting to it all other being endowed with reason? I will allow that no interest urges me to this, for that would not give a categorical imperative, but I must take an interest in it and discern how this comes to pass; for this properly an "I ought" is properly an "I would," valid for every rational being, provided only that reason determined his actions without any hindrance. But for beings that are in addition affected as we are by springs of a different kind, namely, sensibility, and in whose case that is not always done which reason alone would do, for these that necessity is expressed only as an "ought," and the subjective necessity is different from the objective.

It seems then as if the moral law, that is, the principle of autonomy of the will, were properly speaking only presupposed in the idea of freedom, and as if we could not prove its reality and objective necessity independently. In that case we should still have gained something considerable by at least determining the true principle more exactly than had previously been done; but as regards its validity and the practical necessity of subjecting oneself to it, we should not have advanced a step. For if we were asked why the universal validity of our maxim as a law must be the condition restricting our actions, and on what we ground the worth which we assign to this manner of acting- a worth so great that there cannot be any higher interest; and if we were asked further how it happens that it is by this alone a man believes he feels his own personal worth, in comparison with which that of an agreeable or disagreeable condition is to be regarded as nothing, to these questions we could give no satisfactory answer.

We find indeed sometimes that we can take an interest in a personal quality which does not involve any interest of external condition, provided this quality makes us capable of participating in the condition in case reason were to effect the allotment; that is to say, the mere being worthy of happiness can interest of itself even without the motive of participating in this happiness. This judgement, however, is in fact only the effect of the importance of the moral law which we before presupposed (when by the idea of freedom we detach ourselves from every empirical interest); but that we ought to detach ourselves from these interests, i.e., to consider ourselves as free in action and yet as subject to certain laws, so as to find a worth simply in our own person which can compensate us for the loss of everything that gives worth to our condition; this we are not yet able to discern in this way, nor do we see how it is possible so to act- in other words, whence the moral law derives its obligation.

It must be freely admitted that there is a sort of circle here from which it seems impossible to escape. In the order of efficient causes we assume ourselves free, in order that in the order of ends we may conceive ourselves as subject to moral laws: and we afterwards conceive ourselves as subject to these laws, because we have attributed to ourselves freedom of will: for freedom and self-legislation of will are both autonomy and, therefore, are reciprocal conceptions, and for this very reason one must not be used to explain the other or give the reason of it, but at most only logical purposes to reduce apparently different notions of the same object to one single concept (as we reduce different fractions of the same value to the lowest terms).

One resource remains to us, namely, to inquire whether we do not occupy different points of view when by means of freedom we think ourselves as causes efficient a priori, and when we form our conception of ourselves from our actions as effects which we see before our eyes.

It is a remark which needs no subtle reflection to make, but which we may assume that even the commonest understanding can make, although it be after its fashion by an obscure discernment of judgement which it calls feeling, that all the "ideas" that come to us involuntarily (as those of the senses) do not enable us to know objects otherwise than as they affect us; so that what they may be in themselves remains unknown to us, and consequently that as regards "ideas" of this kind even with the closest attention and clearness that the understanding can apply to them, we can by them only attain to the knowledge of appearances, never to that of things in themselves. As soon as this distinction has once been made (perhaps merely in consequence of the difference observed between the ideas given us from without, and in which we are passive, and those that we produce simply from ourselves, and in which we show our own activity), then it follows of itself that we must admit and assume behind the appearance something else that is not an appearance, namely, the things in themselves; although we must admit that as they can never be known to us except as they affect us, we can come no nearer to them, nor can we ever know what they are in themselves. This must furnish a distinction, however crude, between a world of sense and the world of understanding, of which the former may be different according to the difference of the sensuous impressions in various observers, while the second which is its basis always remains the same, Even as to himself, a man cannot pretend to know what he is in himself from the knowledge he has by internal sensation. For as he does not as it were create himself, and does not come by the conception of himself a priori but empirically, it naturally follows that he can obtain his knowledge even of himself only by the inner sense and, consequently, only through the appearances of his nature and the way in which his consciousness is affected. At the same time beyond these characteristics of his own subject, made up of mere appearances, he must necessarily suppose something else as their basis, namely, his ego, whatever its characteristics in itself may be. Thus in respect to mere perception and receptivity of sensations he must reckon himself as belonging to the world of sense; but in respect of whatever there may be of pure activity in him (that which reaches consciousness immediately and not through affecting the senses), he must reckon himself as belonging to the intellectual world, of which, however, he has no further knowledge. To such a conclusion the reflecting man must come with respect to all the things which can be presented to him: it is probably to be met with even in persons of the commonest understanding, who, as is well known, are very much inclined to suppose behind the objects of the senses something else invisible and acting of itself. They spoil it, however, by presently sensualizing this invisible again; that is to say, wanting to make it an object of intuition, so that they do not become a whit the wiser.

Now man really finds in himself a faculty by which he distinguishes himself from everything else, even from himself as affected by objects, and that is reason. This being pure spontaneity is even elevated above the understanding. For although the latter is a spontaneity and does not, like sense, merely contain intuitions that arise when we are affected by things (and are therefore passive), yet it cannot produce from its activity any other conceptions than those which merely serve to bring the intuitions of sense under rules and, thereby, to unite them in one consciousness, and without this use of the sensibility it could not think at all; whereas, on the contrary, reason shows so pure a spontaneity in the case of what I call ideas [ideal conceptions] that it thereby far transcends everything that the sensibility can give it, and exhibits its most important function in distinguishing the world of sense from that of understanding, and thereby prescribing the limits of the understanding itself.

For this reason a rational being must regard himself qua intelligence (not from the side of his lower faculties) as belonging not to the world of sense, but to that of understanding; hence he has two points of view from which he can regard himself, and recognise laws of the exercise of his faculties, and consequently of all his actions: first, so far as he belongs to the world of sense, he finds himself subject to laws of nature (heteronomy); secondly, as belonging to the intelligible world, under laws which being independent of nature have their foundation not in experience but in reason alone.

As a rational being, and consequently belonging to the intelligible world, man can never conceive the causality of his own will otherwise than on condition of the idea of freedom, for independence of the determinate causes of the sensible world (an independence which reason must always ascribe to itself) is freedom. Now the idea of freedom is inseparably connected with the conception of autonomy, and this again with the universal principle of morality which is ideally the foundation of all actions of rational beings, just as the law of nature is of all phenomena.

Now the suspicion is removed which we raised above, that there was a latent circle involved in our reasoning from freedom to autonomy, and from this to the moral law, viz.: that we laid down the idea of freedom because of the moral law only that we might afterwards in turn infer the latter from freedom, and that consequently we could assign no reason at all for this law, but could only [present] it as a petitio principii which well disposed minds would gladly concede to us, but which we could never put forward as a provable proposition. For now we see that, when we conceive ourselves as free, we transfer ourselves into the world of understanding as members of it and recognise the autonomy of the will with its consequence, morality; whereas, if we conceive ourselves as under obligation, we consider ourselves as belonging to the world of sense and at the same time to the world of understanding.



How is a Categorical Imperative Possible?



Every rational being reckons himself qua intelligence as belonging to the world of understanding, and it is simply as an efficient cause belonging to that world that he calls his causality a will. On the other side he is also conscious of himself as a part of the world of sense in which his actions, which are mere appearances [phenomena] of that causality, are displayed; we cannot, however, discern how they are possible from this causality which we do not know; but instead of that, these actions as belonging to the sensible world must be viewed as determined by other phenomena, namely, desires and inclinations. If therefore I were only a member of the world of understanding, then all my actions would perfectly conform to the principle of autonomy of the pure will; if I were only a part of the world of sense, they would necessarily be assumed to conform wholly to the natural law of desires and inclinations, in other words, to the heteronomy of nature. (The former would rest on morality as the supreme principle, the latter on happiness.) Since, however, the world of understanding contains the foundation of the world of sense, and consequently of its laws also, and accordingly gives the law to my will (which belongs wholly to the world of understanding) directly, and must be conceived as doing so, it follows that, although on the one side I must regard myself as a being belonging to the world of sense, yet on the other side I must recognize myself as subject as an intelligence to the law of the world of understanding, i.e., to reason, which contains this law in the idea of freedom, and therefore as subject to the autonomy of the will: consequently I must regard the laws of the world of understanding as imperatives for me and the actions which conform to them as duties.

And thus what makes categorical imperatives possible is this, that the idea of freedom makes me a member of an intelligible world, in consequence of which, if I were nothing else, all my actions would always conform to the autonomy of the will; but as I at the same time intuite myself as a member of the world of sense, they ought so to conform, and this categorical "ought" implies a synthetic a priori proposition, inasmuch as besides my will as affected by sensible desires there is added further the idea of the same will but as belonging to the world of the understanding, pure and practical of itself, which contains the supreme condition according to reason of the former will; precisely as to the intuitions of sense there are added concepts of the understanding which of themselves signify nothing but regular form in general and in this way synthetic a priori propositions become possible, on which all knowledge of physical nature rests.

The practical use of common human reason confirms this reasoning. There is no one, not even the most consummate villain, provided only that he is otherwise accustomed to the use of reason, who, when we set before him examples of honesty of purpose, of steadfastness in following good maxims, of sympathy and general benevolence (even combined with great sacrifices of advantages and comfort), does not wish that he might also possess these qualities. Only on account of his inclinations and impulses he cannot attain this in himself, but at the same time he wishes to be free from such inclinations which are burdensome to himself. He proves by this that he transfers himself in thought with a will free from the impulses of the sensibility into an order of things wholly different from that of his desires in the field of the sensibility; since he cannot expect to obtain by that wish any gratification of his desires, nor any position which would satisfy any of his actual or supposable inclinations (for this would destroy the pre-eminence of the very idea which wrests that wish from him): he can only expect a greater intrinsic worth of his own person. This better person, however, he imagines himself to be when be transfers himself to the point of view of a member of the world of the understanding, to which he is involuntarily forced by the idea of freedom, i.e., of independence on determining causes of the world of sense; and from this point of view he is conscious of a good will, which by his own confession constitutes the law for the bad will that he possesses as a member of the world of sense- a law whose authority he recognizes while transgressing it. What he morally "ought" is then what he necessarily "would," as a member of the world of the understanding, and is conceived by him as an "ought" only inasmuch as he likewise considers himself as a member of the world of sense.



Of the Extreme Limits of all Practical Philosophy.



All men attribute to themselves freedom of will. Hence come all judgements upon actions as being such as ought to have been done, although they have not been done. However, this freedom is not a conception of experience, nor can it be so, since it still remains, even though experience shows the contrary of what on supposition of freedom are conceived as its necessary consequences. On the other side it is equally necessary that everything that takes place should be fixedly determined according to laws of nature. This necessity of nature is likewise not an empirical conception, just for this reason, that it involves the motion of necessity and consequently of a priori cognition. But this conception of a system of nature is confirmed by experience; and it must even be inevitably presupposed if experience itself is to be possible, that is, a connected knowledge of the objects of sense resting on general laws. Therefore freedom is only an idea of reason, and its objective reality in itself is doubtful; while nature is a concept of the understanding which proves, and must necessarily prove, its reality in examples of experience.

There arises from this a dialectic of reason, since the freedom attributed to the will appears to contradict the necessity of nature, and placed between these two ways reason for speculative purposes finds the road of physical necessity much more beaten and more appropriate than that of freedom; yet for practical purposes the narrow footpath of freedom is the only one on which it is possible to make use of reason in our conduct; hence it is just as impossible for the subtlest philosophy as for the commonest reason of men to argue away freedom. Philosophy must then assume that no real contradiction will be found between freedom and physical necessity of the same human actions, for it cannot give up the conception of nature any more than that of freedom.

Nevertheless, even though we should never be able to comprehend how freedom is possible, we must at least remove this apparent contradiction in a convincing manner. For if the thought of freedom contradicts either itself or nature, which is equally necessary, it must in competition with physical necessity be entirely given up.

It would, however, be impossible to escape this contradiction if the thinking subject, which seems to itself free, conceived itself in the same sense or in the very same relation when it calls itself free as when in respect of the same action it assumes itself to be subject to the law of nature. Hence it is an indispensable problem of speculative philosophy to show that its illusion respecting the contradiction rests on this, that we think of man in a different sense and relation when we call him free and when we regard him as subject to the laws of nature as being part and parcel of nature. It must therefore show that not only can both these very well co-exist, but that both must be thought as necessarily united in the same subject, since otherwise no reason could be given why we should burden reason with an idea which, though it may possibly without contradiction be reconciled with another that is sufficiently established, yet entangles us in a perplexity which sorely embarrasses reason in its theoretic employment. This duty, however, belongs only to speculative philosophy. The philosopher then has no option whether he will remove the apparent contradiction or leave it untouched; for in the latter case the theory respecting this would be bonum vacans, into the possession of which the fatalist would have a right to enter and chase all morality out of its supposed domain as occupying it without title.

We cannot however as yet say that we are touching the bounds of practical philosophy. For the settlement of that controversy does not belong to it; it only demands from speculative reason that it should put an end to the discord in which it entangles itself in theoretical questions, so that practical reason may have rest and security from external attacks which might make the ground debatable on which it desires to build.

The claims to freedom of will made even by common reason are founded on the consciousness and the admitted supposition that reason is independent of merely subjectively determined causes which together constitute what belongs to sensation only and which consequently come under the general designation of sensibility. Man considering himself in this way as an intelligence places himself thereby in a different order of things and in a relation to determining grounds of a wholly different kind when on the one hand he thinks of himself as an intelligence endowed with a will, and consequently with causality, and when on the other he perceives himself as a phenomenon in the world of sense (as he really is also), and affirms that his causality is subject to external determination according to laws of nature. Now he soon becomes aware that both can hold good, nay, must hold good at the same time. For there is not the smallest contradiction in saying that a thing in appearance (belonging to the world of sense) is subject to certain laws, of which the very same as a thing or being in itself is independent, and that he must conceive and think of himself in this twofold way, rests as to the first on the consciousness of himself as an object affected through the senses, and as to the second on the consciousness of himself as an intelligence, i.e., as independent on sensible impressions in the employment of his reason (in other words as belonging to the world of understanding).

Hence it comes to pass that man claims the possession of a will which takes no account of anything that comes under the head of desires and inclinations and, on the contrary, conceives actions as possible to him, nay, even as necessary which can only be done by disregarding all desires and sensible inclinations. The causality of such actions lies in him as an intelligence and in the laws of effects and actions [which depend] on the principles of an intelligible world, of which indeed he knows nothing more than that in it pure reason alone independent of sensibility gives the law; moreover since it is only in that world, as an intelligence, that he is his proper self (being as man only the appearance of himself), those laws apply to him directly and categorically, so that the incitements of inclinations and appetites (in other words the whole nature of the world of sense) cannot impair the laws of his volition as an intelligence. Nay, he does not even hold himself responsible for the former or ascribe them to his proper self, i.e., his will: he only ascribes to his will any indulgence which he might yield them if he allowed them to influence his maxims to the prejudice of the rational laws of the will.

When practical reason thinks itself into a world of understanding, it does not thereby transcend its own limits, as it would if it tried to enter it by intuition or sensation. The former is only a negative thought in respect of the world of sense, which does not give any laws to reason in determining the will and is positive only in this single point that this freedom as a negative characteristic is at the same time conjoined with a (positive) faculty and even with a causality of reason, which we designate a will, namely a faculty of so acting that the principle of the actions shall conform to the essential character of a rational motive, i.e., the condition that the maxim have universal validity as a law. But were it to borrow an object of will, that is, a motive, from the world of understanding, then it would overstep its bounds and pretend to be acquainted with something of which it knows nothing. The conception of a world of the understanding is then only a point of view which reason finds itself compelled to take outside the appearances in order to conceive itself as practical, which would not be possible if the influences of the sensibility had a determining power on man, but which is necessary unless he is to be denied the consciousness of himself as an intelligence and, consequently, as a rational cause, energizing by reason, that is, operating freely. This thought certainly involves the idea of an order and a system of laws different from that of the mechanism of nature which belongs to the sensible world; and it makes the conception of an intelligible world necessary (that is to say, the whole system of rational beings as things in themselves). But it does not in the least authorize us to think of it further than as to its formal condition only, that is, the universality of the maxims of the will as laws, and consequently the autonomy of the latter, which alone is consistent with its freedom; whereas, on the contrary, all laws that refer to a definite object give heteronomy, which only belongs to laws of nature and can only apply to the sensible world.

But reason would overstep all its bounds if it undertook to explain how pure reason can be practical, which would be exactly the same problem as to explain how freedom is possible.

For we can explain nothing but that which we can reduce to laws, the object of which can be given in some possible experience. But freedom is a mere idea, the objective reality of which can in no wise be shown according to laws of nature, and consequently not in any possible experience; and for this reason it can never be comprehended or understood, because we cannot support it by any sort of example or analogy. It holds good only as a necessary hypothesis of reason in a being that believes itself conscious of a will, that is, of a faculty distinct from mere desire (namely, a faculty of determining itself to action as an intelligence, in other words, by laws of reason independently on natural instincts). Now where determination according to laws of nature ceases, there all explanation ceases also, and nothing remains but defence, i.e., the removal of the objections of those who pretend to have seen deeper into the nature of things, and thereupon boldly declare freedom impossible. We can only point out to them that the supposed contradiction that they have discovered in it arises only from this, that in order to be able to apply the law of nature to human actions, they must necessarily consider man as an appearance: then when we demand of them that they should also think of him qua intelligence as a thing in itself, they still persist in considering him in this respect also as an appearance. In this view it would no doubt be a contradiction to suppose the causality of the same subject (that is, his will) to be withdrawn from all the natural laws of the sensible world. But this contradiction disappears, if they would only bethink themselves and admit, as is reasonable, that behind the appearances there must also lie at their root (although hidden) the things in themselves, and that we cannot expect the laws of these to be the same as those that govern their appearances.

The subjective impossibility of explaining the freedom of the will is identical with the impossibility of discovering and explaining an interest * which man can take in the moral law. Nevertheless he does actually take an interest in it, the basis of which in us we call the moral feeling, which some have falsely assigned as the standard of our moral judgement, whereas it must rather be viewed as the subjective effect that the law exercises on the will, the objective principle of which is furnished by reason alone.



* Interest is that by which reason becomes practical, i.e., a cause determining the will. Hence we say of rational beings only that they take an interest in a thing; irrational beings only feel sensual appetites. Reason takes a direct interest in action then only when the universal validity of its maxims is alone sufficient to determine the will. Such an interest alone is pure. But if it can determine the will only by means of another object of desire or on the suggestion of a particular feeling of the subject, then reason takes only an indirect interest in the action, and, as reason by itself without experience cannot discover either objects of the will or a special feeling actuating it, this latter interest would only be empirical and not a pure rational interest. The logical interest of reason (namely, to extend its insight) is never direct, but presupposes purposes for which reason is employed.



In order indeed that a rational being who is also affected through the senses should will what reason alone directs such beings that they ought to will, it is no doubt requisite that reason should have a power to infuse a feeling of pleasure or satisfaction in the fulfilment of duty, that is to say, that it should have a causality by which it determines the sensibility according to its own principles. But it is quite impossible to discern, i.e., to make it intelligible a priori, how a mere thought, which itself contains nothing sensible, can itself produce a sensation of pleasure or pain; for this is a particular kind of causality of which as of every other causality we can determine nothing whatever a priori; we must only consult experience about it. But as this cannot supply us with any relation of cause and effect except between two objects of experience, whereas in this case, although indeed the effect produced lies within experience, yet the cause is supposed to be pure reason acting through mere ideas which offer no object to experience, it follows that for us men it is quite impossible to explain how and why the universality of the maxim as a law, that is, morality, interests. This only is certain, that it is not because it interests us that it has validity for us (for that would be heteronomy and dependence of practical reason on sensibility, namely, on a feeling as its principle, in which case it could never give moral laws), but that it interests us because it is valid for us as men, inasmuch as it had its source in our will as intelligences, in other words, in our proper self, and what belongs to mere appearance is necessarily subordinated by reason to the nature of the thing in itself.

The question then, "How a categorical imperative is possible," can be answered to this extent, that we can assign the only hypothesis on which it is possible, namely, the idea of freedom; and we can also discern the necessity of this hypothesis, and this is sufficient for the practical exercise of reason, that is, for the conviction of the validity of this imperative, and hence of the moral law; but how this hypothesis itself is possible can never be discerned by any human reason. On the hypothesis, however, that the will of an intelligence is free, its autonomy, as the essential formal condition of its determination, is a necessary consequence. Moreover, this freedom of will is not merely quite possible as a hypothesis (not involving any contradiction to the principle of physical necessity in the connexion of the phenomena of the sensible world) as speculative philosophy can show: but further, a rational being who is conscious of causality through reason, that is to say, of a will (distinct from desires), must of necessity make it practically, that is, in idea, the condition of all his voluntary actions. But to explain how pure reason can be of itself practical without the aid of any spring of action that could be derived from any other source, i.e., how the mere principle of the universal validity of all its maxims as laws (which would certainly be the form of a pure practical reason) can of itself supply a spring, without any matter (object) of the will in which one could antecedently take any interest; and how it can produce an interest which would be called purely moral; or in other words, how pure reason can be practical- to explain this is beyond the power of human reason, and all the labour and pains of seeking an explanation of it are lost.

It is just the same as if I sought to find out how freedom itself is possible as the causality of a will. For then I quit the ground of philosophical explanation, and I have no other to go upon. I might indeed revel in the world of intelligences which still remains to me, but although I have an idea of it which is well founded, yet I have not the least knowledge of it, nor an I ever attain to such knowledge with all the efforts of my natural faculty of reason. It signifies only a something that remains over when I have eliminated everything belonging to the world of sense from the actuating principles of my will, serving merely to keep in bounds the principle of motives taken from the field of sensibility; fixing its limits and showing that it does not contain all in all within itself, but that there is more beyond it; but this something more I know no further. Of pure reason which frames this ideal, there remains after the abstraction of all matter, i.e., knowledge of objects, nothing but the form, namely, the practical law of the universality of the maxims, and in conformity with this conception of reason in reference to a pure world of understanding as a possible efficient cause, that is a cause determining the will. There must here be a total absence of springs; unless this idea of an intelligible world is itself the spring, or that in which reason primarily takes an interest; but to make this intelligible is precisely the problem that we cannot solve.

Here now is the extreme limit of all moral inquiry, and it is of great importance to determine it even on this account, in order that reason may not on the one band, to the prejudice of morals, seek about in the world of sense for the supreme motive and an interest comprehensible but empirical; and on the other hand, that it may not impotently flap its wings without being able to move in the (for it) empty space of transcendent concepts which we call the intelligible world, and so lose itself amidst chimeras. For the rest, the idea of a pure world of understanding as a system of all intelligences, and to which we ourselves as rational beings belong (although we are likewise on the other side members of the sensible world), this remains always a useful and legitimate idea for the purposes of rational belief, although all knowledge stops at its threshold, useful, namely, to produce in us a lively interest in the moral law by means of the noble ideal of a universal kingdom of ends in themselves (rational beings), to which we can belong as members then only when we carefully conduct ourselves according to the maxims of freedom as if they were laws of nature.



Concluding Remark



The speculative employment of reason with respect to nature leads to the absolute necessity of some supreme cause of the world: the practical employment of reason with a view to freedom leads also to absolute necessity, but only of the laws of the actions of a rational being as such. Now it is an essential principle of reason, however employed, to push its knowledge to a consciousness of its necessity (without which it would not be rational knowledge). It is, however, an equally essential restriction of the same reason that it can neither discern the necessity of what is or what happens, nor of what ought to happen, unless a condition is supposed on which it is or happens or ought to happen. In this way, however, by the constant inquiry for the condition, the satisfaction of reason is only further and further postponed. Hence it unceasingly seeks the unconditionally necessary and finds itself forced to assume it, although without any means of making it comprehensible to itself, happy enough if only it can discover a conception which agrees with this assumption. It is therefore no fault in our deduction of the supreme principle of morality, but an objection that should be made to human reason in general, that it cannot enable us to conceive the absolute necessity of an unconditional practical law (such as the categorical imperative must be). It cannot be blamed for refusing to explain this necessity by a condition, that is to say, by means of some interest assumed as a basis, since the law would then cease to be a supreme law of reason. And thus while we do not comprehend the practical unconditional necessity of the moral imperative, we yet comprehend its incomprehensibility, and this is all that can be fairly demanded of a philosophy which strives to carry its principles up to the very limit of human reason.

THE END