Pure Reason's Dialectic in Defining the "Summum Bonum"

The conception of the summum itself contains an ambiguity which might occasion needless disputes if we did not attend to it. The summum may mean either the supreme (supremum) or the perfect (consummatum). The former is that condition which is itself unconditioned, i.e., is not subordinate to any other (originarium); the second is that whole which is not a part of a greater whole of the same kind (perfectissimum). It has been shown in the Analytic that virtue (as worthiness to be happy) is the supreme condition of all that can appear to us desirable, and consequently of all our pursuit of happiness, and is therefore the supreme good. But it does not follow that it is the whole and perfect good as the object of the desires of rational finite beings; for this requires happiness also, and that not merely in the partial eyes of the person who makes himself an end, but even in the judgement of an impartial reason, which regards persons in general as ends in themselves. For to need happiness, to deserve it, and yet at the same time not to participate in it, cannot be consistent with the perfect volition of a rational being possessed at the same time of all power, if, for the sake of experiment, we conceive such a being. Now inasmuch as virtue and happiness together constitute the possession of the summum bonum in a person, and the distribution of happiness in exact proportion to morality (which is the worth of the person, and his worthiness to be happy) constitutes the summum bonum of a possible world; hence this summum bonum expresses the whole, the perfect good, in which, however, virtue as the condition is always the supreme good, since it has no condition above it; whereas happiness, while it is pleasant to the possessor of it, is not of itself absolutely and in all respects good, but always presupposes morally right behaviour as its condition.

The concept of the summum is ambiguous, and this could cause needless disputes if we do not notice it. The summum can mean either the supreme (supremum) or the perfect (consummatum). The supreme is a condition that is itself unconditioned, meaning that it is not subordinate to any other condition (originarium). The perfect is a whole that is not part of a greater whole of the same kind (perfectissimum). The Analytic has shown that virtue, understood as worthiness to be happy, is the supreme condition of everything we can find desirable. It is therefore also the supreme condition of all our pursuit of happiness, and so it is the supreme good. But it does not follow that virtue is the whole and perfect good desired by finite rational beings. The perfect good also requires happiness. This is true not merely in the partial view of a person who treats himself as an end. It is true even in the judgment of impartial reason, which regards persons in general as ends in themselves. We might, for the sake of experiment, imagine a rational being who also has all power. The perfect will of such a being could not allow someone to need happiness and deserve it, yet not receive it. Virtue and happiness together constitute a person's possession of the summum bonum. In a possible world, the summum bonum consists in happiness distributed in exact proportion to morality. Morality is a person's worth and worthiness to be happy. The summum bonum thus expresses the whole, perfect good. Within it, however, virtue is always the supreme good as the condition of happiness, since virtue has no condition above it. Happiness, by contrast, is pleasant to the person who possesses it. But happiness is not in itself absolutely good in every respect. It always depends on morally right behavior as its condition.

When two elements are necessarily united in one concept, they must be connected as reason and consequence, and this either so that their unity is considered as analytical (logical connection), or as synthetical (real connection) the former following the law of identity, the latter that of causality. The connection of virtue and happiness may therefore be understood in two ways: either the endeavour to be virtuous and the rational pursuit of happiness are not two distinct actions, but absolutely identical, in which case no maxim need be made the principle of the former, other than what serves for the latter; or the connection consists in this, that virtue produces happiness as something distinct from the consciousness of virtue, as a cause produces an effect.

When two elements are necessarily united in one concept, they must be connected as reason and consequence. Their unity can be understood as either analytical (a logical connection) or synthetic (a real connection). The analytical connection follows the law of identity, while the synthetic connection follows the law of causality. The connection between virtue and happiness may therefore be understood in two ways. First, striving to be virtuous and rationally pursuing happiness may be not two distinct actions, but exactly the same action. In that case, the same maxim can serve as the principle for both. Alternatively, virtue produces happiness as something distinct from the consciousness of virtue, just as a cause produces an effect.

The ancient Greek schools were, properly speaking, only two, and in determining the conception of the summum bonum these followed in fact one and the same method, inasmuch as they did not allow virtue and happiness to be regarded as two distinct elements of the summum bonum, and consequently sought the unity of the principle by the rule of identity; but they differed as to which of the two was to be taken as the fundamental notion. The Epicurean said: "To be conscious that one's maxims lead to happiness is virtue"; the Stoic said: "To be conscious of one's virtue is happiness." With the former, Prudence was equivalent to morality; with the latter, who chose a higher designation for virtue, morality alone was true wisdom.

Strictly speaking, there were only two ancient Greek schools. Both used the same method to define the summum bonum, or highest good. Neither regarded virtue and happiness as two distinct elements of the highest good. Both therefore sought a single principle by treating virtue and happiness as identical. But they differed over which of the two was more fundamental. The Epicurean said: "Virtue is knowing that one's maxims lead to happiness." The Stoic said: "Happiness is knowing that one is virtuous." For the Epicurean, prudence was equivalent to morality. For the Stoic, who gave virtue a higher title, morality alone was true wisdom.

While we must admire the men who in such early times tried all imaginable ways of extending the domain of philosophy, we must at the same time lament that their acuteness was unfortunately misapplied in trying to trace out identity between two extremely heterogeneous notions, those of happiness and virtue. But it agrees with the dialectical spirit of their times (and subtle minds are even now sometimes misled in the same way) to get rid of irreconcilable differences in principle by seeking to change them into a mere contest about words, and thus apparently working out the identity of the notion under different names, and this usually occurs in cases where the combination of heterogeneous principles lies so deep or so high, or would require so complete a transformation of the doctrines assumed in the rest of the philosophical system, that men are afraid to penetrate deeply into the real difference and prefer treating it as a difference in questions of form.

We must admire the men who, so early in history, tried every imaginable way to expand the scope of philosophy. At the same time, we must regret that they misused their sharp minds. They tried to show that two very different ideas, happiness and virtue, were identical. But their approach was in keeping with the spirit of debate in their times. Subtle thinkers are sometimes misled in the same way even now. They try to dispose of irreconcilable differences in principle by turning them into mere disputes about words. In this way, they seem to show that the same idea has different names. This usually happens when combining different principles is a very deep or lofty problem. It also happens when combining them would require a complete transformation of the doctrines assumed elsewhere in the philosophical system. In such cases, people are afraid to examine the real difference closely. They prefer to treat it as a difference in matters of form.

While both schools sought to trace out the identity of the practical principles of virtue and happiness, they were not agreed as to the way in which they tried to force this identity, but were separated infinitely from one another, the one placing its principle on the side of sense, the other on that of reason; the one in the consciousness of sensible wants, the other in the independence of practical reason on all sensible grounds of determination. According to the Epicurean, the notion of virtue was already involved in the maxim: "To promote one's own happiness"; according to the Stoics, on the other hand, the feeling of happiness was already contained in the consciousness of virtue. Now whatever is contained in another notion is identical with part of the containing notion, but not with the whole, and moreover two wholes may be specifically distinct, although they consist of the same parts; namely if the parts are united into a whole in totally different ways. The Stoic maintained that the virtue was the whole summum bonum, and happiness only the consciousness of possessing it, as making part of the state of the subject. The Epicurean maintained that happiness was the whole summum bonum, and virtue only the form of the maxim for its pursuit; viz., the rational use of the means for attaining it.

Both schools tried to establish that the practical principles of virtue and happiness were identical. But they disagreed on how to force this identity, and they were infinitely far apart. One school based its principle on the senses, the other on reason. One based its principle on awareness of needs felt through the senses. The other based its principle on the independence of practical reason from all determining grounds provided by the senses. According to the Epicureans, the concept of virtue was already included in the maxim: "Promote one's own happiness". According to the Stoics, on the other hand, the feeling of happiness was already contained in the awareness of virtue. Now, whatever is contained in another concept is identical to part of that concept, but not to the whole. Moreover, two wholes may differ in kind, although they consist of the same parts. They may differ if their parts are combined into wholes in completely different ways. The Stoics maintained that virtue was the whole summum bonum, or highest good. For them, happiness was only the awareness of possessing virtue, as part of a person's state. The Epicureans maintained that happiness was the whole summum bonum. For them, virtue was only the form of the maxim for pursuing happiness, namely, the rational use of the means to attain it.

Now it is clear from the Analytic that the maxims of virtue and those of private happiness are quite heterogeneous as to their supreme practical principle, and, although they belong to one summum bonum which together they make possible, yet they are so far from coinciding that they restrict and check one another very much in the same subject. Thus the question: "How is the summum bonum practically possible?" still remains an unsolved problem, notwithstanding all the attempts at coalition that have hitherto been made. The Analytic has, however, shown what it is that makes the problem difficult to solve; namely, that happiness and morality are two specifically distinct elements of the summum bonum and, therefore, their combination cannot be analytically cognised (as if the man that seeks his own happiness should find by mere analysis of his conception that in so acting he is virtuous, or as if the man that follows virtue should in the consciousness of such conduct find that he is already happy ipso facto), but must be a synthesis of concepts. Now since this combination is recognised as a priori, and therefore as practically necessary, and consequently not as derived from experience, so that the possibility of the summum bonum does not rest on any empirical principle, it follows that the deduction [legitimation] of this concept must be transcendental. It is a priori (morally) necessary to produce the summum bonum by freedom of will: therefore the condition of its possibility must rest solely on a priori principles of cognition.

The Analytic makes clear that the maxims of virtue and those of private happiness have quite different supreme practical principles. Although both belong to the summum bonum, which they make possible together, they do not coincide. Rather, in the same person, they greatly restrict and check one another. Thus the question, "How is the summum bonum practically possible?" remains unsolved, despite all attempts so far to unite them. The Analytic has, however, shown what makes the problem difficult to solve. Happiness and morality are two specifically distinct elements of the summum bonum. Their combination therefore cannot be known through analysis alone. It is not as if a person seeking happiness could, merely by analyzing that idea, discover that doing so is virtuous. Nor is it as if a person following virtue could find, in the awareness of that conduct, that they are already happy simply by virtue of it. Instead, the combination must be a synthesis of concepts. This combination is recognized a priori and is therefore practically necessary, not derived from experience. So the possibility of the summum bonum does not rest on any empirical principle. It follows that the deduction [legitimation] of this concept must be transcendental. It is necessary a priori (morally) to produce the summum bonum through freedom of will. Therefore, the condition for its possibility must rest solely on a priori principles of cognition.

In the summum bonum which is practical for us, i.e., to be realized by our will, virtue and happiness are thought as necessarily combined, so that the one cannot be assumed by pure practical reason without the other also being attached to it. Now this combination (like every other) is either analytical or synthetical. It has been shown that it cannot be analytical; it must then be synthetical and, more particularly, must be conceived as the connection of cause and effect, since it concerns a practical good, i.e., one that is possible by means of action; consequently either the desire of happiness must be the motive to maxims of virtue, or the maxim of virtue must be the efficient cause of happiness. The first is absolutely impossible, because (as was proved in the Analytic) maxims which place the determining principle of the will in the desire of personal happiness are not moral at all, and no virtue can be founded on them. But the second is also impossible, because the practical connection of causes and effects in the world, as the result of the determination of the will, does not depend upon the moral dispositions of the will, but on the knowledge of the laws of nature and the physical power to use them for one's purposes; consequently we cannot expect in the world by the most punctilious observance of the moral laws any necessary connection of happiness with virtue adequate to the summum bonum. Now, as the promotion of this summum bonum, the conception of which contains this connection, is a priori a necessary object of our will and inseparably attached to the moral law, the impossibility of the former must prove the falsity of the latter. If then the supreme good is not possible by practical rules, then the moral law also which commands us to promote it is directed to vain imaginary ends and must consequently be false.

In the supreme good (summum bonum) that is practical for us, virtue and happiness are necessarily joined. By practical, I mean a good that our will can bring about. Pure practical reason cannot assume one without also attaching the other to it. Now this connection, like every other, is either analytical or synthetic. It has been shown that it cannot be analytical, so it must be synthetic. More specifically, it must be understood as a connection between cause and effect. This is because it concerns a practical good, one that is possible through action. So either the desire for happiness must motivate the principles of virtue, or the principle of virtue must produce happiness. The first possibility is absolutely impossible. As was proved in the Analytic, principles that base the will’s decisions on the desire for personal happiness are not moral at all. No virtue can be founded on them. But the second possibility is also impossible. When the will determines an action, the practical connection between cause and effect in the world does not depend on the will’s moral dispositions. It depends on knowledge of natural laws and the physical power to use them for one’s purposes. So even by observing moral laws with the utmost care, we cannot expect a necessary connection between virtue and happiness in the world that would be adequate to the supreme good. Now promoting this supreme good is a necessary object of our will a priori, and it is inseparably attached to the moral law. The idea of the supreme good includes this connection between virtue and happiness. So if the supreme good is impossible, the moral law must be false. If the supreme good cannot be achieved through practical rules, then the moral law commands us to promote an empty, imaginary goal. The moral law must therefore be false.

The antinomy of pure speculative reason exhibits a similar conflict between freedom and physical necessity in the causality of events in the world. It was solved by showing that there is no real contradiction when the events and even the world in which they occur are regarded (as they ought to be) merely as appearances; since one and the same acting being, as an appearance (even to his own inner sense), has a causality in the world of sense that always conforms to the mechanism of nature, but with respect to the same events, so far as the acting person regards himself at the same time as a noumenon (as pure intelligence in an existence not dependent on the condition of time), he can contain a principle by which that causality acting according to laws of nature is determined, but which is itself free from all laws of nature.

The antinomy of pure speculative reason shows a similar conflict between freedom and physical necessity in what causes events in the world. The conflict was resolved by showing that there is no real contradiction. There is no contradiction when events and the world in which they occur are regarded merely as appearances, as they ought to be. As an appearance, even to their own inner sense, an acting person exercises causality in the world of sense. This causality always conforms to the mechanism of nature. But the same person can also regard themselves as a noumenon, or pure intelligence, whose existence does not depend on time. In this respect, the person can contain a principle that determines the causality governing the same events. Although this causality operates according to laws of nature, the principle itself is free from all laws of nature.

It is just the same with the foregoing antinomy of pure practical reason. The first of the two propositions, "That the endeavour after happiness produces a virtuous mind," is absolutely false; but the second, "That a virtuous mind necessarily produces happiness," is not absolutely false, but only in so far as virtue is considered as a form of causality in the sensible world, and consequently only if I suppose existence in it to be the only sort of existence of a rational being; it is then only conditionally false. But as I am not only justified in thinking that I exist also as a noumenon in a world of the understanding, but even have in the moral law a purely intellectual determining principle of my causality (in the sensible world), it is not impossible that morality of mind should have a connection as cause with happiness (as an effect in the sensible world) if not immediate yet mediate (viz., through an intelligent author of nature), and moreover necessary; while in a system of nature which is merely an object of the senses, this combination could never occur except contingently and, therefore, could not suffice for the summum bonum.

The same is true of the antinomy of pure practical reason just discussed. The first proposition, "The pursuit of happiness produces a virtuous mind," is absolutely false. But the second, "A virtuous mind necessarily produces happiness," is not absolutely false. It is false only if virtue is considered a form of causality in the sensible world, and I assume that a rational being exists only in that world. The second proposition is therefore only conditionally false. But I am justified in thinking that I also exist as a noumenon in a world of the understanding. Moreover, the moral law gives me a purely intellectual principle that determines my causality in the sensible world. So it is not impossible that a moral mind should cause happiness as an effect in the sensible world. This connection might be necessary, though not direct, but indirect, through an intelligent author of nature. In a system of nature that is merely an object of the senses, however, morality and happiness could coincide only by chance. Such a chance connection could not suffice for the summum bonum.

Thus, notwithstanding this seeming conflict of practical reason with itself, the summum bonum, which is the necessary supreme end of a will morally determined, is a true object thereof; for it is practically possible, and the maxims of the will which as regards their matter refer to it have objective reality, which at first was threatened by the antinomy that appeared in the connection of morality with happiness by a general law; but this was merely from a misconception, because the relation between appearances was taken for a relation of the things in themselves to these appearances.

Thus, despite this apparent conflict within practical reason, the summum bonum remains a genuine object of the will. It is the necessary supreme end of a morally determined will, and it is practically possible. The maxims of the will whose content concerns the summum bonum have objective reality. At first, an apparent antinomy threatened this objective reality. The antinomy seemed to arise from the connection between morality and happiness under a general law. But this was merely a misunderstanding. It arose because the relation between appearances was mistaken for a relation between things in themselves and those appearances.

When we find ourselves obliged to go so far, namely, to the connection with an intelligible world, to find the possibility of the summum bonum, which reason points out to all rational beings as the goal of all their moral wishes, it must seem strange that, nevertheless, the philosophers both of ancient and modern times have been able to find happiness in accurate proportion to virtue even in this life (in the sensible world), or have persuaded themselves that they were conscious thereof. For Epicurus as well as the Stoics extolled above everything the happiness that springs from the consciousness of living virtuously; and the former was not so base in his practical precepts as one might infer from the principles of his theory, which he used for explanation and not for action, or as they were interpreted by many who were misled by his using the term pleasure for contentment; on the contrary, he reckoned the most disinterested practice of good amongst the ways of enjoying the most intimate delight, and his scheme of pleasure (by which he meant constant cheerfulness of mind) included the moderation and control of the inclinations, such as the strictest moral philosopher might require. He differed from the Stoics chiefly in making this pleasure the motive, which they very rightly refused to do. For, on the one hand, the virtuous Epicurus, like many well-intentioned men of this day who do not reflect deeply enough on their principles, fell into the error of presupposing the virtuous disposition in the persons for whom he wished to provide the springs to virtue (and indeed the upright man cannot be happy if he is not first conscious of his uprightness; since with such a character the reproach that his habit of thought would oblige him to make against himself in case of transgression and his moral self-condemnation would rob him of all enjoyment of the pleasantness which his condition might otherwise contain). But the question is: How is such a disposition possible in the first instance, and such a habit of thought in estimating the worth of one's existence, since prior to it there can be in the subject no feeling at all for moral worth? If a man is virtuous without being conscious of his integrity in every action, he will certainly not enjoy life, however favourable fortune may be to him in its physical circumstances; but can we make him virtuous in the first instance, in other words, before he esteems the moral worth of his existence so highly, by praising to him the peace of mind that would result from the consciousness of an integrity for which he has no sense?

We find ourselves obliged to go so far as to connect with an intelligible world to understand how the summum bonum is possible. Reason presents the summum bonum to all rational beings as the goal of all their moral wishes. Given this, something must seem strange. Philosophers, both ancient and modern, have found happiness exactly proportional to virtue even in this life, in the sensible world. Or they have persuaded themselves that they were aware of such happiness. Both Epicurus and the Stoics praised the happiness that comes from knowing one lives virtuously above all else. Epicurus was not as base in his practical advice as one might infer from the principles of his theory. He used those principles to explain things, not to guide action. Nor was he as base as many people thought. They were misled because he used the word pleasure to mean contentment. On the contrary, he counted the most disinterested practice of good among the ways to enjoy the deepest delight. By pleasure he meant a constant cheerfulness of mind. His account of pleasure included the moderation and control of desires, as even the strictest moral philosopher might require. His main difference from the Stoics was that he made this pleasure the motive for virtue. The Stoics were quite right to refuse to do so. For the virtuous Epicurus fell into an error, like many well intentioned people today who do not reflect deeply enough on their principles. He assumed that the people he wished to provide with motives for virtue already had a virtuous disposition. An upright person, it is true, cannot be happy without first being aware of their own uprightness. For if such a person did wrong, their way of thinking would compel them to reproach themselves. Their moral self-condemnation would rob them of all enjoyment of whatever pleasures their circumstances might otherwise contain. But the question is how such a disposition can arise in the first place. How can someone come to judge the worth of their own existence in this way? Before acquiring this disposition, a person can have no feeling at all for moral worth. A virtuous person who is not conscious of their integrity in every action will certainly not enjoy life. This remains true however favorable their physical circumstances may be. But can we make someone virtuous in the first place by praising the peace of mind that comes from being conscious of integrity? Can we do this before the person values the moral worth of their existence so highly, and when they have no sense of that integrity?

On the other hand, however, there is here an occasion of a vitium subreptionis, and as it were of an optical illusion, in the self-consciousness of what one does as distinguished from what one feels- an illusion which even the most experienced cannot altogether avoid. The moral disposition of mind is necessarily combined with a consciousness that the will is determined directly by the law. Now the consciousness of a determination of the faculty of desire is always the source of a satisfaction in the resulting action; but this pleasure, this satisfaction in oneself, is not the determining principle of the action; on the contrary, the determination of the will directly by reason is the source of the feeling of pleasure, and this remains a pure practical not sensible determination of the faculty of desire. Now as this determination has exactly the same effect within in impelling to activity, that a feeling of the pleasure to be expected from the desired action would have had, we easily look on what we ourselves do as something which we merely passively feel, and take the moral spring for a sensible impulse, just as it happens in the so-called illusion of the senses (in this case the inner sense). It is a sublime thing in human nature to be determined to actions immediately by a purely rational law; sublime even is the illusion that regards the subjective side of this capacity of intellectual determination as something sensible and the effect of a special sensible feeling (for an intellectual feeling would be a contradiction). It is also of great importance to attend to this property of our personality and as much as possible to cultivate the effect of reason on this feeling. But we must beware lest by falsely extolling this moral determining principle as a spring, making its source lie in particular feelings of pleasure (which are in fact only results), we degrade and disfigure the true genuine spring, the law itself, by putting as it were a false foil upon it. Respect, not pleasure or enjoyment of happiness, is something for which it is not possible that reason should have any antecedent feeling as its foundation (for this would always be sensible and pathological); and consciousness of immediate obligation of the will by the law is by no means analogous to the feeling of pleasure, although in relation to the faculty of desire it produces the same effect, but from different sources: it is only by this mode of conception, however, that we can attain what we are seeking, namely, that actions be done not merely in accordance with duty (as a result of pleasant feelings), but from duty, which must be the true end of all moral cultivation.

On the other hand, there is room here for a vitium subreptionis, a kind of optical illusion in self-awareness. It concerns the distinction between what we do and what we feel. Even the most experienced people cannot altogether avoid this illusion. A moral disposition necessarily involves awareness that the law directly determines the will. Now, awareness that our capacity for desire has been determined always produces satisfaction in the resulting action. But this pleasure, this satisfaction in ourselves, is not what determines the action. On the contrary, the feeling of pleasure comes from reason directly determining the will. This remains a purely practical, not a sensory, determination of our capacity for desire. Yet this determination has the same effect within us as the feeling of pleasure we expect from a desired action. Both prompt us to act. So we easily regard what we ourselves do as something we merely feel passively. We mistake the moral motive for a sensory impulse. This is like what happens in the so-called illusion of the senses, in this case, the inner sense. It is sublime that human nature can be led to act directly by a purely rational law. Even the illusion is sublime. It treats the subjective side of this capacity to be determined by reason as something sensory, caused by a special sensory feeling. An intellectual feeling would be a contradiction. It is also very important to attend to this feature of our personality. We should, as much as possible, cultivate the effect of reason on this feeling. But we must beware of falsely praising this moral determining principle as a motive by tracing it to particular feelings of pleasure. These feelings are in fact only results. In doing so, we degrade and distort the true, genuine motive, the law itself, as if we were putting a false decorative backing on it. Respect, unlike pleasure or the enjoyment of happiness, cannot be based on any feeling that reason has beforehand. Such a feeling would always be sensory and pathological. Nor is awareness that the law directly binds the will at all like a feeling of pleasure. Although it has the same effect on our capacity for desire, the two come from different sources. Only by understanding the matter in this way can we achieve what we seek. Actions must be done not merely in accordance with duty, as a result of pleasant feelings, but from duty. That must be the true goal of all moral cultivation.

Have we not, however, a word which does not express enjoyment, as happiness does, but indicates a satisfaction in one's existence, an analogue of the happiness which must necessarily accompany the consciousness of virtue? Yes this word is self-contentment which in its proper signification always designates only a negative satisfaction in one's existence, in which one is conscious of needing nothing. Freedom and the consciousness of it as a faculty of following the moral law with unyielding resolution is independence of inclinations, at least as motives determining (though not as affecting) our desire, and so far as I am conscious of this freedom in following my moral maxims, it is the only source of an unaltered contentment which is necessarily connected with it and rests on no special feeling. This may be called intellectual contentment. The sensible contentment (improperly so-called) which rests on the satisfaction of the inclinations, however delicate they may be imagined to be, can never be adequate to the conception of it. For the inclinations change, they grow with the indulgence shown them, and always leave behind a still greater void than we had thought to fill. Hence they are always burdensome to a rational being, and, although he cannot lay them aside, they wrest from him the wish to be rid of them. Even an inclination to what is right (e.g., to beneficence), though it may much facilitate the efficacy of the moral maxims, cannot produce any. For in these all must be directed to the conception of the law as a determining principle, if the action is to contain morality and not merely legality. Inclination is blind and slavish, whether it be of a good sort or not, and, when morality is in question, reason must not play the part merely of guardian to inclination, but disregarding it altogether must attend simply to its own interest as pure practical reason. This very feeling of compassion and tender sympathy, if it precedes the deliberation on the question of duty and becomes a determining principle, is even annoying to right thinking persons, brings their deliberate maxims into confusion, and makes them wish to be delivered from it and to be subject to lawgiving reason alone.

But do we not have a word for satisfaction with one's existence that does not express enjoyment, as happiness does? Does it not describe something like the happiness that must accompany an awareness of virtue? Yes. The word is self-contentment. Properly understood, it always means only a negative satisfaction with one's existence, in which one is aware of needing nothing. Freedom, and awareness of freedom as the ability to follow the moral law with unwavering resolve, means independence from inclinations. It means independence from them at least as motives that determine our desires, though not as influences on them. When I am aware of this freedom in following my moral principles, it is the only source of a lasting contentment. This contentment is necessarily connected with that freedom and rests on no particular feeling. It may be called intellectual contentment. Contentment based on feeling, as it is improperly called, rests on satisfying our inclinations, however refined we imagine them to be. It can never live up to the idea of contentment. Inclinations change, grow when we indulge them, and always leave a greater emptiness than we had hoped to fill. So they are always burdensome to a rational being. Although a rational being cannot set inclinations aside, they force the wish to be rid of them. Even an inclination toward what is right, such as an inclination to help others, cannot produce moral principles. It may greatly help those principles take effect. But if an action is to be moral and not merely lawful, everything in those principles must be directed toward the idea of the law as the determining principle. Inclination is blind and slavish, whether it is good or not. When morality is at issue, reason must not merely act as inclination's guardian. It must disregard inclination altogether and attend only to its own interest as pure practical reason. The very feeling of compassion and tender sympathy can come before deliberation about duty and become a determining principle. If it does, it is even troubling to people who think rightly. It confuses the principles they have carefully chosen. It makes them wish to be free of the feeling and subject only to reason as the giver of law.

From this we can understand how the consciousness of this faculty of a pure practical reason produces by action (virtue) a consciousness of mastery over one's inclinations, and therefore of independence of them, and consequently also of the discontent that always accompanies them, and thus a negative satisfaction with one's state, i.e., contentment, which is primarily contentment with one's own person. Freedom itself becomes in this way (namely, indirectly) capable of an enjoyment which cannot be called happiness, because it does not depend on the positive concurrence of a feeling, nor is it, strictly speaking, bliss, since it does not include complete independence of inclinations and wants, but it resembles bliss in so far as the determination of one's will at least can hold itself free from their influence; and thus, at least in its origin, this enjoyment is analogous to the self-sufficiency which we can ascribe only to the Supreme Being.

From this, we can understand how awareness of our capacity for pure practical reason leads to another awareness through virtuous action. It makes us aware that we can master our inclinations and are therefore independent of them. As a result, we are also independent of the discontent that always accompanies them. This gives us a negative satisfaction with our condition, a contentment that is primarily contentment with ourselves. In this indirect way, freedom itself becomes capable of enjoyment. This enjoyment cannot be called happiness, because it does not depend on the presence of a positive feeling. Nor is it strictly speaking bliss, since it does not include complete independence from inclinations and wants. But it resembles bliss insofar as the determination of our will can at least remain free from their influence. Thus, at least in its origin, this enjoyment is like the self-sufficiency we can ascribe only to the Supreme Being.

From this solution of the antinomy of practical pure reason, it follows that in practical principles we may at least conceive as possible a natural and necessary connection between the consciousness of morality and the expectation of a proportionate happiness as its result, though it does not follow that we can know or perceive this connection; that, on the other hand, principles of the pursuit of happiness cannot possibly produce morality; that, therefore, morality is the supreme good (as the first condition of the summum bonum), while happiness constitutes its second element, but only in such a way that it is the morally conditioned, but necessary consequence of the former. Only with this subordination is the summum bonum the whole object of pure practical reason, which must necessarily conceive it as possible, since it commands us to contribute to the utmost of our power to its realization. But since the possibility of such connection of the conditioned with its condition belongs wholly to the supersensual relation of things and cannot be given according to the laws of the world of sense, although the practical consequences of the idea belong to the world of sense, namely, the actions that aim at realizing the summum bonum; we will therefore endeavour to set forth the grounds of that possibility, first, in respect of what is immediately in our power, and then, secondly, in that which is not in our power, but which reason presents to us as the supplement of our impotence, for the realization of the summum bonum (which by practical principles is necessary).

This solution to the antinomy of pure practical reason leads to several conclusions. In practical principles, we can at least conceive of a natural and necessary connection as possible. The connection is between consciousness of morality and the expectation of a corresponding happiness as its result. But it does not follow that we can know or perceive this connection. On the other hand, principles based on the pursuit of happiness cannot possibly produce morality. Morality is therefore the supreme good, the first condition of the summum bonum. Happiness is its second element, but only as a necessary consequence of morality, one that depends on morality as its condition. Only when happiness is subordinate to morality is the summum bonum the complete object of pure practical reason. Reason must conceive of it as possible, since reason commands us to do everything in our power to help bring it about. But the possibility of this connection between happiness and morality belongs entirely to the supersensible relation of things. It cannot be given according to the laws of the world of sense. The practical consequences of the idea do belong to the world of sense, however. These are the actions that aim to bring about the summum bonum. We will therefore try to explain the grounds for the possibility of this connection. First, we will consider what is directly in our power. Second, we will consider what is not in our power, but what reason presents as making up for our inability. This would make it possible to bring about the summum bonum, which practical principles make necessary.

By primacy between two or more things connected by reason, I understand the prerogative, belonging to one, of being the first determining principle in the connection with all the rest. In a narrower practical sense it means the prerogative of the interest of one in so far as the interest of the other is subordinated to it, while it is not postponed to any other. To every faculty of the mind we can attribute an interest, that is, a principle, that contains the condition on which alone the former is called into exercise. Reason, as the faculty of principles, determines the interest of all the powers of the mind and is determined by its own. The interest of its speculative employment consists in the cognition of the object pushed to the highest a priori principles: that of its practical employment, in the determination of the will in respect of the final and complete end. As to what is necessary for the possibility of any employment of reason at all, namely, that its principles and affirmations should not contradict one another, this constitutes no part of its interest, but is the condition of having reason at all; it is only its development, not mere consistency with itself, that is reckoned as its interest.

By primacy among two or more things connected by reason, I mean the priority one has as the first determining principle in its connection with all the others. In a narrower practical sense, primacy means the priority of one interest over another. The other interest is subordinate to it, while it is not subordinate to any other interest. We can attribute an interest to every faculty of the mind. By interest, I mean a principle that contains the condition under which alone that faculty is exercised. Reason, as the faculty of principles, determines the interest of all the powers of the mind. Its own interest determines reason itself. The interest of speculative reason is to know its object by tracing that knowledge back to the highest a priori principles. The interest of practical reason is to determine the will in relation to the final and complete end. For any use of reason to be possible, its principles and assertions must not contradict one another. This is not part of reason’s interest, but a condition of having reason at all. Only the development of reason, not its mere consistency with itself, counts as its interest.

If practical reason could not assume or think as given anything further than what speculative reason of itself could offer it from its own insight, the latter would have the primacy. But supposing that it had of itself original a priori principles with which certain theoretical positions were inseparably connected, while these were withdrawn from any possible insight of speculative reason (which, however, they must not contradict); then the question is: Which interest is the superior (not which must give way, for they are not necessarily conflicting), whether speculative reason, which knows nothing of all that the practical offers for its acceptance, should take up these propositions and (although they transcend it) try to unite them with its own concepts as a foreign possession handed over to it, or whether it is justified in obstinately following its own separate interest and, according to the canonic of Epicurus, rejecting as vain subtlety everything that cannot accredit its objective reality by manifest examples to be shown in experience, even though it should be never so much interwoven with the interest of the practical (pure) use of reason, and in itself not contradictory to the theoretical, merely because it infringes on the interest of the speculative reason to this extent, that it removes the bounds which this latter had set to itself, and gives it up to every nonsense or delusion of imagination?

If practical reason could assume or take as given only what speculative reason could discover on its own, speculative reason would have primacy. But suppose practical reason had its own original a priori principles, inseparably connected with certain theoretical propositions. Suppose also that these propositions were beyond any possible insight of speculative reason, though they must not contradict it. Then the question is: Which interest is superior? The question is not which must give way, because the two interests do not necessarily conflict. Speculative reason knows nothing of what practical reason offers it for acceptance. Should speculative reason accept these propositions, even though they lie beyond its reach? Should it try to unite them with its own concepts, as a foreign possession handed over to it? Or is speculative reason justified in stubbornly pursuing its own separate interest? Following the canon of Epicurus, it would reject as empty subtlety everything whose objective reality cannot be established by clear examples from experience. Would it be justified in doing so, however closely such propositions might be interwoven with the interest of the practical (pure) use of reason, and even if they did not in themselves contradict theoretical reason? Would it be justified in rejecting them merely because they infringe on the interest of speculative reason? For they remove the bounds speculative reason has set for itself and leave it open to every nonsense or delusion of imagination.

In fact, so far as practical reason is taken as dependent on pathological conditions, that is, as merely regulating the inclinations under the sensible principle of happiness, we could not require speculative reason to take its principles from such a source. Mohammed's paradise, or the absorption into the Deity of the theosophists and mystics would press their monstrosities on the reason according to the taste of each, and one might as well have no reason as surrender it in such fashion to all sorts of dreams. But if pure reason of itself can be practical and is actually so, as the consciousness of the moral law proves, then it is still only one and the same reason which, whether in a theoretical or a practical point of view, judges according to a priori principles; and then it is clear that although it is in the first point of view incompetent to establish certain propositions positively, which, however, do not contradict it, then, as soon as these propositions are inseparably attached to the practical interest of pure reason, it must accept them, though it be as something offered to it from a foreign source, something that has not grown on its own ground, but yet is sufficiently authenticated; and it must try to compare and connect them with everything that it has in its power as speculative reason. It must remember, however, that these are not additions to its insight, but yet are extensions of its employment in another, namely, a practical aspect; and this is not in the least opposed to its interest, which consists in the restriction of wild speculation.

In fact, practical reason may be understood as dependent on conditions of feeling and desire. In that case, it merely governs our inclinations according to the principle of happiness based on the senses. We could not demand that speculative reason take its principles from such a source. Mohammed's paradise, or the theosophists' and mystics' absorption into the Deity, would impose their monstrosities on reason according to each person's taste. One might as well have no reason as surrender it to all sorts of dreams. But pure reason may itself be practical, and our awareness of the moral law proves that it actually is. In that case, it is still one and the same reason that judges by a priori principles, whether theoretically or practically. From the theoretical point of view, reason cannot establish certain propositions positively, although they do not contradict it. But once these propositions are inseparably connected with the practical interest of pure reason, reason must accept them. They come from a foreign source, so to speak, rather than growing on reason's own theoretical ground. Yet they are sufficiently supported. Reason must also try to compare and connect them with everything within its power as speculative reason. It must remember, however, that these propositions add nothing to its insight. Instead, they extend its use in another respect, namely, the practical one. This extension does not conflict at all with reason's interest, which is to limit wild speculation.

Thus, when pure speculative and pure practical reason are combined in one cognition, the latter has the primacy, provided, namely, that this combination is not contingent and arbitrary, but founded a priori on reason itself and therefore necessary. For without this subordination there would arise a conflict of reason with itself; since, if they were merely co-ordinate, the former would close its boundaries strictly and admit nothing from the latter into its domain, while the latter would extend its bounds over everything and when its needs required would seek to embrace the former within them. Nor could we reverse the order and require pure practical reason to be subordinate to the speculative, since all interest is ultimately practical, and even that of speculative reason is conditional, and it is only in the practical employment of reason that it is complete.

When pure speculative reason and pure practical reason are combined in one body of knowledge, practical reason takes priority. This is so, provided that the combination is not accidental or arbitrary, but grounded a priori in reason itself and therefore necessary. Without this subordination, reason would conflict with itself. For if speculative and practical reason had equal standing, speculative reason would strictly close its boundaries. It would admit nothing from practical reason into its domain. Practical reason, meanwhile, would extend its boundaries over everything. When its needs required it, practical reason would seek to include speculative reason within its domain. Nor could we reverse the order and require pure practical reason to be subordinate to speculative reason. For all interest is ultimately practical. Even the interest of speculative reason is conditional, and it is complete only in the practical use of reason.

The realization of the summum bonum in the world is the necessary object of a will determinable by the moral law. But in this will the perfect accordance of the mind with the moral law is the supreme condition of the summum bonum. This then must be possible, as well as its object, since it is contained in the command to promote the latter. Now, the perfect accordance of the will with the moral law is holiness, a perfection of which no rational being of the sensible world is capable at any moment of his existence. Since, nevertheless, it is required as practically necessary, it can only be found in a progress in infinitum towards that perfect accordance, and on the principles of pure practical reason it is necessary to assume such a practical progress as the real object of our will.

Bringing about the summum bonum, or highest good, in the world is the necessary object of a will that can be guided by the moral law. But the highest condition of the summum bonum is that the mind of the person willing it agrees perfectly with the moral law. This perfect agreement must therefore be possible, as must the summum bonum itself. Both are implied by the command to promote the summum bonum. Perfect agreement between the will and the moral law is holiness. No rational being in the sensible world is capable of this perfection at any moment of its existence. Yet holiness is required as practically necessary. It can therefore be found only in endless progress toward that perfect agreement. And the principles of pure practical reason require us to assume that such practical progress is the real object of our will.

Now, this endless progress is only possible on the supposition of an endless duration of the existence and personality of the same rational being (which is called the immortality of the soul). The summum bonum, then, practically is only possible on the supposition of the immortality of the soul; consequently this immortality, being inseparably connected with the moral law, is a postulate of pure practical reason (by which I mean a theoretical proposition, not demonstrable as such, but which is an inseparable result of an unconditional a priori practical law.

This endless progress is possible only if the same rational being continues to exist as the same person forever. This is called the immortality of the soul. The summum bonum, then, is practically possible only if the soul is immortal. Consequently, the soul’s immortality is a postulate of pure practical reason, since it is inseparably connected with the moral law. By a postulate, I mean a theoretical proposition that cannot itself be demonstrated. But it follows inseparably from an unconditional a priori practical law.

This principle of the moral destination of our nature, namely, that it is only in an endless progress that we can attain perfect accordance with the moral law, is of the greatest use, not merely for the present purpose of supplementing the impotence of speculative reason, but also with respect to religion. In default of it, either the moral law is quite degraded from its holiness, being made out to be indulgent and conformable to our convenience, or else men strain their notions of their vocation and their expectation to an unattainable goal, hoping to acquire complete holiness of will, and so they lose themselves in fanatical theosophic dreams, which wholly contradict self-knowledge. In both cases the unceasing effort to obey punctually and thoroughly a strict and inflexible command of reason, which yet is not ideal but real, is only hindered. For a rational but finite being, the only thing possible is an endless progress from the lower to higher degrees of moral perfection. The Infinite Being, to whom the condition of time is nothing, sees in this to us endless succession a whole of accordance with the moral law; and the holiness which his command inexorably requires, in order to be true to his justice in the share which He assigns to each in the summum bonum, is to be found in a single intellectual intuition of the whole existence of rational beings. All that can be expected of the creature in respect of the hope of this participation would be the consciousness of his tried character, by which from the progress he has hitherto made from the worse to the morally better, and the immutability of purpose which has thus become known to him, he may hope for a further unbroken continuance of the same, however long his existence may last, even beyond this life, * and thus he may hope, not indeed here, nor in any imaginable point of his future existence, but only in the endlessness of his duration (which God alone can survey) to be perfectly adequate to his will (without indulgence or excuse, which do not harmonize with justice).

This principle concerns the moral purpose of our nature. It holds that we can achieve perfect conformity with the moral law only through endless progress. The principle is extremely useful, not only for our present purpose of making up for the limitations of speculative reason, but also for religion. Without it, either the moral law is stripped of its holiness and made to seem forgiving and suited to our convenience, or people set their sights and hopes on an unreachable goal. They hope to achieve complete holiness of will and lose themselves in fanatical theosophic dreams that wholly contradict self-knowledge. In both cases, the result is an obstacle to the unceasing effort to obey a strict and inflexible command of reason, precisely and completely. Yet this command is not merely an ideal but real. For a rational but finite being, the only possibility is endless progress from lower to higher degrees of moral perfection. The Infinite Being, for whom time is no constraint, sees this succession, endless to us, as a whole that conforms to the moral law. His command requires holiness without exception, so that he may be true to his justice in assigning each being a share in the summum bonum. This holiness is found in a single intellectual intuition of the whole existence of rational beings. All that can be expected of a creature who hopes to share in the summum bonum is an awareness of character tested by experience. From past progress from worse to morally better, and from the constancy of purpose revealed through that progress, the creature may hope to continue improving without interruption, however long its existence may last, even beyond this life, * and so may hope to conform perfectly to God's will. This hope does not concern the present life or any imaginable point in the creature's future existence. It concerns only the endlessness of its existence, which God alone can survey. Such conformity would require no indulgence or excuse, neither of which is compatible with justice.

In the foregoing analysis the moral law led to a practical problem which is prescribed by pure reason alone, without the aid of any sensible motives, namely, that of the necessary completeness of the first and principle element of the summum bonum, viz., morality; and, as this can be perfectly solved only in eternity, to the postulate of immortality. The same law must also lead us to affirm the possibility of the second element of the summum bonum, viz., happiness proportioned to that morality, and this on grounds as disinterested as before, and solely from impartial reason; that is, it must lead to the supposition of the existence of a cause adequate to this effect; in other words, it must postulate the existence of God, as the necessary condition of the possibility of the summum bonum (an object of the will which is necessarily connected with the moral legislation of pure reason). We proceed to exhibit this connection in a convincing manner.

In the preceding analysis, the moral law led to a practical problem set by pure reason alone, without help from any motive based on feeling. The problem was the necessary completeness of morality, the first and principal element of the summum bonum, or highest good. Since this problem can be perfectly solved only in eternity, it led to the postulate of immortality. The same law must also lead us to affirm the possibility of the second element of the summum bonum: happiness in proportion to morality. It must do so on equally disinterested grounds, arising solely from impartial reason. In other words, the moral law must lead us to suppose that a cause exists that is adequate to produce such happiness. It must therefore postulate the existence of God as a necessary condition for the possibility of the summum bonum. The summum bonum is an object of the will that is necessarily connected with the moral laws of pure reason. We will now show this connection in a convincing way.

Happiness is the condition of a rational being in the world with whom everything goes according to his wish and will; it rests, therefore, on the harmony of physical nature with his whole end and likewise with the essential determining principle of his will. Now the moral law as a law of freedom commands by determining principles, which ought to be quite independent of nature and of its harmony with our faculty of desire (as springs). But the acting rational being in the world is not the cause of the world and of nature itself. There is not the least ground, therefore, in the moral law for a necessary connection between morality and proportionate happiness in a being that belongs to the world as part of it, and therefore dependent on it, and which for that reason cannot by his will be a cause of this nature, nor by his own power make it thoroughly harmonize, as far as his happiness is concerned, with his practical principles. Nevertheless, in the practical problem of pure reason, i.e., the necessary pursuit of the summum bonum, such a connection is postulated as necessary: we ought to endeavour to promote the summum bonum, which, therefore, must be possible. Accordingly, the existence of a cause of all nature, distinct from nature itself and containing the principle of this connection, namely, of the exact harmony of happiness with morality, is also postulated. Now this supreme cause must contain the principle of the harmony of nature, not merely with a law of the will of rational beings, but with the conception of this law, in so far as they make it the supreme determining principle of the will, and consequently not merely with the form of morals, but with their morality as their motive, that is, with their moral character. Therefore, the summum bonum is possible in the world only on the supposition of a Supreme Being having a causality corresponding to moral character. Now a being that is capable of acting on the conception of laws is an intelligence (a rational being), and the causality of such a being according to this conception of laws is his will; therefore the supreme cause of nature, which must be presupposed as a condition of the summum bonum is a being which is the cause of nature by intelligence and will, consequently its author, that is God. It follows that the postulate of the possibility of the highest derived good (the best world) is likewise the postulate of the reality of a highest original good, that is to say, of the existence of God. Now it was seen to be a duty for us to promote the summum bonum; consequently it is not merely allowable, but it is a necessity connected with duty as a requisite, that we should presuppose the possibility of this summum bonum; and as this is possible only on condition of the existence of God, it inseparably connects the supposition of this with duty; that is, it is morally necessary to assume the existence of God.

Happiness is the condition of a rational being in the world for whom everything goes as they wish and will. Happiness therefore depends on physical nature being in harmony with all their ends and with the essential principle determining their will. But the moral law is a law of freedom. It commands through principles that should be entirely independent of nature and of its harmony with our desires as motives. A rational being who acts in the world, however, is not the cause of the world or of nature itself. Such a being is part of the world and depends on it. Therefore, the being cannot cause nature through its will or, by its own power, bring nature fully into harmony with its practical principles so as to ensure its happiness. The moral law therefore gives no grounds at all for a necessary connection between morality and proportionate happiness in such a being. Nevertheless, in the practical task of pure reason, such a connection is assumed to be necessary. That task is the necessary pursuit of the summum bonum, or highest good. We ought to try to promote the summum bonum, so it must be possible. Accordingly, we must also assume that there is a cause of all nature, distinct from nature itself. This cause must contain the basis for that connection, namely, the exact harmony of happiness with morality. This supreme cause must contain the basis for nature's harmony not merely with a law governing rational beings' wills. Nature must also be in harmony with their conception of this law, insofar as they make it the supreme principle determining their wills. In other words, nature must be in harmony not merely with outward conformity to moral rules, but with morality as their motive, that is, with their moral character. The summum bonum is therefore possible in the world only if we assume a Supreme Being whose power to cause things accords with moral character. A being capable of acting according to its conception of laws is an intelligence, or a rational being. Its power to cause things according to that conception of laws is its will. Therefore, the supreme cause of nature must be presupposed as a condition of the summum bonum. This cause is a being that causes nature through intelligence and will. It is therefore the author of nature, that is, God. It follows that assuming the possibility of the highest derived good, or the best world, also means assuming the reality of a highest original good, that is, the existence of God. We have seen that we have a duty to promote the summum bonum. Therefore, assuming that the summum bonum is possible is not merely permitted. It is also necessary as a requirement connected with duty. The summum bonum is possible only if God exists. Therefore, our duty is inseparably connected with the assumption that God exists. In other words, it is morally necessary to assume the existence of God.

It must be remarked here that this moral necessity is subjective, that is, it is a want, and not objective, that is, itself a duty, for there cannot be a duty to suppose the existence of anything (since this concerns only the theoretical employment of reason). Moreover, it is not meant by this that it is necessary to suppose the existence of God as a basis of all obligation in general (for this rests, as has been sufficiently proved, simply on the autonomy of reason itself). What belongs to duty here is only the endeavour to realize and promote the summum bonum in the world, the possibility of which can therefore be postulated; and as our reason finds it not conceivable except on the supposition of a supreme intelligence, the admission of this existence is therefore connected with the consciousness of our duty, although the admission itself belongs to the domain of speculative reason. Considered in respect of this alone, as a principle of explanation, it may be called a hypothesis, but in reference to the intelligibility of an object given us by the moral law (the summum bonum), and consequently of a requirement for practical purposes, it may be called faith, that is to say a pure rational faith, since pure reason (both in its theoretical and practical use) is the sole source from which it springs.

It should be noted here that this moral necessity is subjective. It is a need, not an objective duty in itself. There can be no duty to assume that anything exists, since this concerns only the theoretical use of reason. Nor does this mean that we must assume God exists as the basis of all obligation. As has been sufficiently proved, all obligation rests simply on the autonomy of reason itself. Our only duty here is to strive to realize and promote the summum bonum, or highest good, in the world. We can therefore postulate that the summum bonum is possible. But our reason cannot conceive of its possibility except on the assumption that a supreme intelligence exists. Accepting the existence of a supreme intelligence is therefore connected with our consciousness of duty, although this acceptance itself belongs to speculative reason. Considered only as a principle of explanation, this acceptance may be called a hypothesis. But it may be called faith insofar as it makes an object given to us by the moral law intelligible. That object is the summum bonum, and accepting the supreme intelligence is consequently a requirement for practical purposes. More specifically, it may be called pure rational faith, since pure reason, in both its theoretical and practical use, is its sole source.

From this deduction it is now intelligible why the Greek schools could never attain the solution of their problem of the practical possibility of the summum bonum, because they made the rule of the use which the will of man makes of his freedom the sole and sufficient ground of this possibility, thinking that they had no need for that purpose of the existence of God. No doubt they were so far right that they established the principle of morals of itself independently of this postulate, from the relation of reason only to the will, and consequently made it the supreme practical condition of the summum bonum; but it was not therefore the whole condition of its possibility. The Epicureans had indeed assumed as the supreme principle of morality a wholly false one, namely that of happiness, and had substituted for a law a maxim of arbitrary choice according to every man's inclination; they proceeded, however, consistently enough in this, that they degraded their summum bonum likewise, just in proportion to the meanness of their fundamental principle, and looked for no greater happiness than can be attained by human prudence (including temperance and moderation of the inclinations), and this as we know would be scanty enough and would be very different according to circumstances; not to mention the exceptions that their maxims must perpetually admit and which make them incapable of being laws. The Stoics, on the contrary, had chosen their supreme practical principle quite rightly, making virtue the condition of the summum bonum; but when they represented the degree of virtue required by its pure law as fully attainable in this life, they not only strained the moral powers of the man whom they called the wise beyond all the limits of his nature, and assumed a thing that contradicts all our knowledge of men, but also and principally they would not allow the second element of the summum bonum, namely, happiness, to be properly a special object of human desire, but made their wise man, like a divinity in his consciousness of the excellence of his person, wholly independent of nature (as regards his own contentment); they exposed him indeed to the evils of life, but made him not subject to them (at the same time representing him also as free from moral evil). They thus, in fact, left out the second element of the summum bonum namely, personal happiness, placing it solely in action and satisfaction with one's own personal worth, thus including it in the consciousness of being morally minded, in which they Might have been sufficiently refuted by the voice of their own nature.

This deduction now makes clear why the Greek schools could never solve their problem of how the summum bonum was practically possible. They believed that the rule governing how human beings use their freedom was the sole and sufficient basis for this possibility. They thought they had no need to assume the existence of God for this purpose. They were right, certainly, to establish the principle of morality independently of this postulate, based only on the relation of reason to the will. They therefore made morality the supreme practical condition of the summum bonum. But it did not follow that morality was the whole condition of its possibility. The Epicureans adopted an entirely false supreme principle of morality, namely happiness. They replaced a law with a rule of arbitrary choice based on each person's inclination. Yet they were consistent enough to lower their summum bonum in proportion to the lowliness of their basic principle. They sought no greater happiness than human prudence can achieve, including temperance and moderation of the inclinations. As we know, this happiness would be meager enough and would vary greatly with circumstances. Moreover, their rules would constantly need to admit exceptions, making them incapable of being laws. The Stoics, by contrast, chose their supreme practical principle quite rightly. They made virtue the condition of the summum bonum. But they claimed that the degree of virtue required by its pure law was fully attainable in this life. In doing so, they stretched the moral powers of the person they called wise beyond all the limits of human nature. They also assumed something that contradicts all our knowledge of human beings. More importantly, they refused to recognize the second element of the summum bonum, happiness, as a distinct object of human desire. Instead, they made their wise person like a god, conscious of his own excellence and wholly independent of nature for his contentment. They exposed him to the evils of life, but made him immune to them. At the same time, they also portrayed him as free from moral evil. In fact, then, they left out the second element of the summum bonum, personal happiness. They placed happiness solely in action and satisfaction with one's own worth, thus including it in the awareness of having a moral disposition. The voice of their own nature might have been enough to refute them on this point.

The doctrine of Christianity, * even if we do not yet consider it as a religious doctrine, gives, touching this point, a conception of the summum bonum (the kingdom of God), which alone satisfies the strictest demand of practical reason. The moral law is holy (unyielding) and demands holiness of morals, although all the moral perfection to which man can attain is still only virtue, that is, a rightful disposition arising from respect for the law, implying consciousness of a constant propensity to transgression, or at least a want of purity, that is, a mixture of many spurious (not moral) motives of obedience to the law, consequently a self-esteem combined with humility. In respect, then, of the holiness which the Christian law requires, this leaves the creature nothing but a progress in infinitum, but for that very reason it justifies him in hoping for an endless duration of his existence. The worth of a character perfectly accordant with the moral law is infinite, since the only restriction on all possible happiness in the judgement of a wise and all powerful distributor of it is the absence of conformity of rational beings to their duty. But the moral law of itself does not promise any happiness, for according to our conceptions of an order of nature in general, this is not necessarily connected with obedience to the law. Now Christian morality supplies this defect (of the second indispensable element of the summum bonum) by representing the world in which rational beings devote themselves with all their soul to the moral law, as a kingdom of God, in which nature and morality are brought into a harmony foreign to each of itself, by a holy Author who makes the derived summum bonum possible. Holiness of life is prescribed to them as a rule even in this life, while the welfare proportioned to it, namely, bliss, is represented as attainable only in an eternity; because the former must always be the pattern of their conduct in every state, and progress towards it is already possible and necessary in this life; while the latter, under the name of happiness, cannot be attained at all in this world (so far as our own power is concerned), and therefore is made simply an object of hope. Nevertheless, the Christian principle of morality itself is not theological (so as to be heteronomy), but is autonomy of pure practical reason, since it does not make the knowledge of God and His will the foundation of these laws, but only of the attainment of the summum bonum, on condition of following these laws, and it does not even place the proper spring of this obedience in the desired results, but solely in the conception of duty, as that of which the faithful observance alone constitutes the worthiness to obtain those happy consequences.

The doctrine of Christianity, * even if we do not yet consider it a religious doctrine, offers a conception of the summum bonum (the kingdom of God) that alone satisfies the strictest demand of practical reason on this point. The moral law is holy (unyielding) and demands holiness of conduct. Yet all the moral perfection human beings can attain is still only virtue. Virtue is a rightful disposition arising from respect for the law. It involves an awareness of a constant tendency to transgress, or at least a lack of purity. This lack of purity means that many false (nonmoral) motives are mixed in with our obedience to the law. Virtue therefore involves self-esteem combined with humility. In relation to the holiness required by Christian law, this leaves us creatures with nothing but endless progress. But for that very reason, it gives us reason to hope for an endless existence. The worth of a character perfectly in accord with the moral law is infinite. For a wise and all-powerful distributor of happiness would judge that the only limit on any possible happiness is the failure of rational beings to fulfill their duty. But the moral law itself promises no happiness. According to our understanding of the order of nature in general, happiness is not necessarily connected with obedience to the law. Christian morality supplies this missing second essential element of the summum bonum. It presents a world in which rational beings devote themselves wholeheartedly to the moral law as a kingdom of God. In this kingdom, a holy Author brings nature and morality into a harmony that neither has on its own. This Author makes the resulting summum bonum possible. Rational beings are instructed to take holiness of life as their rule even in this life. But the well-being proportionate to holiness, namely bliss, is presented as attainable only in eternity. Holiness must always be the model for their conduct, whatever their condition. Progress toward holiness is already possible and necessary in this life. But the corresponding well-being, under the name of happiness, cannot be attained at all in this world through our own power. It is therefore simply an object of hope. Nevertheless, the Christian principle of morality itself is not theological, and so is not heteronomy. It is the autonomy of pure practical reason. For it does not make knowledge of God and his will the foundation of moral laws. It makes such knowledge the foundation only for attaining the summum bonum, on condition that we follow those laws. Nor does it make the desired results the proper motive for obedience. It places that motive solely in the idea of duty. Only faithful observance of duty makes us worthy of those happy consequences.

In this manner, the moral laws lead through the conception of the summum bonum as the object and final end of pure practical reason to religion, that is, to the recognition of all duties as divine commands, not as sanctions, that is to say, arbitrary ordinances of a foreign and contingent in themselves, but as essential laws of every free will in itself, which, nevertheless, must be regarded as commands of the Supreme Being, because it is only from a morally perfect (holy and good) and at the same time all-powerful will, and consequently only through harmony with this will, that we can hope to attain the summum bonum which the moral law makes it our duty to take as the object of our endeavours. Here again, then, all remains disinterested and founded merely on duty; neither fear nor hope being made the fundamental springs, which if taken as principles would destroy the whole moral worth of actions. The moral law commands me to make the highest possible good in a world the ultimate object of all my conduct. But I cannot hope to effect this otherwise than by the harmony of my will with that of a holy and good Author of the world; and although the conception of the summum bonum as a whole, in which the greatest happiness is conceived as combined in the most exact proportion with the highest degree of moral perfection (possible in creatures), includes my own happiness, yet it is not this that is the determining principle of the will which is enjoined to promote the summum bonum, but the moral law, which, on the contrary, limits by strict conditions my unbounded desire of happiness.

In this way, moral laws lead to religion through the idea of the summum bonum, or highest good. The highest good is the object and final end of pure practical reason. Religion means recognizing all duties as divine commands. But we do not regard them as sanctions, or arbitrary decrees imposed from outside and contingent in themselves. Instead, we regard them as laws essential to every free will in itself. Nevertheless, we must regard them as commands of the Supreme Being. This is because we can hope to attain the highest good only through a morally perfect (holy and good) and all-powerful will. We can therefore hope to attain it only by bringing our will into harmony with that will. The moral law makes it our duty to pursue the highest good. Here again, then, everything remains disinterested and based solely on duty. Neither fear nor hope is treated as the fundamental motive. If either were taken as a principle, it would destroy the entire moral worth of actions. The moral law commands me to make the highest possible good in a world the ultimate object of all my conduct. But I can hope to achieve this only by bringing my will into harmony with that of a holy and good Author of the world. The idea of the summum bonum as a whole includes my own happiness. It combines the greatest happiness with the highest degree of moral perfection possible in creatures, in exact proportion. Yet my happiness is not the principle that determines the will commanded to promote the highest good. Rather, the determining principle is the moral law, which places strict conditions on my unlimited desire for happiness.

Hence also morality is not properly the doctrine how we should make ourselves happy, but how we should become worthy of happiness. It is only when religion is added that there also comes in the hope of participating some day in happiness in proportion as we have endeavoured to be not unworthy of it.

Morality, then, is not really about how to make ourselves happy. It is about how to become worthy of happiness. Only when religion enters the picture can we hope to share in happiness someday. This happiness will be proportional to our efforts to avoid being unworthy of it.

A man is worthy to possess a thing or a state when his possession of it is in harmony with the summum bonum. We can now easily see that all worthiness depends on moral conduct, since in the conception of the summum bonum this constitutes the condition of the rest (which belongs to one's state), namely, the participation of happiness. Now it follows from this that morality should never be treated as a doctrine of happiness, that is, an instruction how to become happy; for it has to do simply with the rational condition (conditio sine qua non) of happiness, not with the means of attaining it. But when morality has been completely expounded (which merely imposes duties instead of providing rules for selfish desires), then first, after the moral desire to promote the summum bonum (to bring the kingdom of God to us) has been awakened, a desire founded on a law, and which could not previously arise in any selfish mind, and when for the behoof of this desire the step to religion has been taken, then this ethical doctrine may be also called a doctrine of happiness because the hope of happiness first begins with religion only.

A person is worthy to possess something or enjoy a certain condition when doing so is in harmony with the summum bonum. We can now easily see that all worthiness depends on moral conduct. In the idea of the summum bonum, moral conduct is the condition for the rest, namely, a person’s share of happiness. Happiness belongs to a person’s condition. It follows that morality should never be treated as a doctrine of happiness, or as instruction in how to become happy. Morality concerns only the rational condition of happiness, a condition without which happiness cannot be deserved, not the means of attaining it. But morality must first be fully explained. It imposes duties rather than providing rules for satisfying selfish desires. Only then can the moral desire to promote the summum bonum, or to bring the kingdom of God to us, be awakened. This desire is founded on a law and could not arise earlier in a selfish mind. When the step to religion has been taken for the sake of this desire, ethical doctrine may also be called a doctrine of happiness. For the hope of happiness begins only with religion.

We can also see from this that, when we ask what is God's ultimate end in creating the world, we must not name the happiness of the rational beings in it, but the summum bonum, which adds a further condition to that wish of such beings, namely, the condition of being worthy of happiness, that is, the morality of these same rational beings, a condition which alone contains the rule by which only they can hope to share in the former at the hand of a wise Author. For as wisdom, theoretically considered, signifies the knowledge of the summum bonum and, practically, the accordance of the will with the summum bonum, we cannot attribute to a supreme independent wisdom an end based merely on goodness. For we cannot conceive the action of this goodness (in respect of the happiness of rational beings) as suitable to the highest original good, except under the restrictive conditions of harmony with the holiness * of his will. Therefore, those who placed the end of creation in the glory of God (provided that this is not conceived anthropomorphically as a desire to be praised) have perhaps hit upon the best expression. For nothing glorifies God more than that which is the most estimable thing in the world, respect for his command, the observance of the holy duty that his law imposes on us, when there is added thereto his glorious plan of crowning such a beautiful order of things with corresponding happiness. If the latter (to speak humanly) makes Him worthy of love, by the former He is an object of adoration. Even men can never acquire respect by benevolence alone, though they may gain love, so that the greatest beneficence only procures them honour when it is regulated by worthiness.

We can also see from this what we should say about God's ultimate purpose in creating the world. We should not say that it is the happiness of the rational beings in it. Instead, it is the summum bonum, or highest good. The highest good adds a further condition to their wish for happiness: they must be worthy of it. This worthiness consists in their morality. Their morality alone provides the rule by which they can hope to receive happiness from a wise Creator. Wisdom, understood in theory, means knowledge of the highest good. In practice, it means willing in accordance with the highest good. So we cannot attribute a purpose based merely on goodness to a supreme, independent wisdom. God's goodness contributes to the happiness of rational beings. But we can see that contribution as suited to the highest original good only if it accords with the holiness * of his will. Therefore, those who said that creation's purpose is the glory of God have perhaps found the best expression. This is true provided that God's glory is not understood in human terms as a desire for praise. Nothing glorifies God more than what is most worthy of esteem in the world. This is respect for his command and observance of the holy duty his law imposes on us. To this is added his glorious plan to crown such a beautiful order with corresponding happiness. If this plan makes him worthy of love, to speak in human terms, respect for his command makes him an object of adoration. Even people can never gain respect through benevolence alone, though they may gain love. So even the greatest acts of kindness earn them honor only when those acts are guided by worthiness.

That in the order of ends, man (and with him every rational being) is an end in himself, that is, that he can never be used merely as a means by any (not even by God) without being at the same time an end also himself, that therefore humanity in our person must be holy to ourselves, this follows now of itself because he is the subject of the moral law, in other words, of that which is holy in itself, and on account of which and in agreement with which alone can anything be termed holy. For this moral law is founded on the autonomy of his will, as a free will which by its universal laws must necessarily be able to agree with that to which it is to submit itself.

In the order of ends, human beings (and every rational being) are ends in themselves. This means that no one, not even God, can use them merely as a means. They must also be treated as ends in themselves. It follows that the humanity in our own person must be sacred to us. This is because each human being is subject to the moral law. The moral law is sacred in itself. Anything can be called sacred only because of this law and in agreement with it. The moral law is based on the autonomy of the human will. As a free will, it must necessarily be able, through its universal laws, to agree with whatever it submits to.

They all proceed from the principle of morality, which is not a postulate but a law, by which reason determines the will directly, which will, because it is so determined as a pure will, requires these necessary conditions of obedience to its precept. These postulates are not theoretical dogmas but, suppositions practically necessary; while then they do [not] extend our speculative knowledge, they give objective reality to the ideas of speculative reason in general (by means of their reference to what is practical), and give it a right to concepts, the possibility even of which it could not otherwise venture to affirm.

They all follow from the principle of morality. This principle is not a postulate but a law, by which reason directly determines the will. Because reason determines the will as a pure will, the will requires these necessary conditions for obeying the law’s command. These postulates are not theoretical dogmas, but practically necessary assumptions. Although they do [not] extend our speculative knowledge, they give objective reality to the ideas of speculative reason in general through their connection to practice. They also entitle speculative reason to use concepts whose possibility it otherwise could not even venture to affirm.

These postulates are those of immortality, freedom positively considered (as the causality of a being so far as he belongs to the intelligible world), and the existence of God. The first results from the practically necessary condition of a duration adequate to the complete fulfilment of the moral law; the second from the necessary supposition of independence of the sensible world, and of the faculty of determining one's will according to the law of an intelligible world, that is, of freedom; the third from the necessary condition of the existence of the summum bonum in such an intelligible world, by the supposition of the supreme independent good, that is, the existence of God.

These postulates are immortality, freedom understood positively, and the existence of God. Freedom understood positively means a being’s power to act as a cause insofar as it belongs to the intelligible world. The first postulate follows from a practical necessity: we need enough time to fulfill the moral law completely. The second follows from another necessary assumption: we are independent of the world of the senses. It also follows from the assumption that we can determine our will according to the law of an intelligible world. This power is freedom. The third follows from a necessary condition for the existence of the summum bonum (the highest good) in such an intelligible world. This condition is the existence of the supreme independent good, that is, the existence of God.

Thus the fact that respect for the moral law necessarily makes the summum bonum an object of our endeavours, and the supposition thence resulting of its objective reality, lead through the postulates of practical reason to conceptions which speculative reason might indeed present as problems, but could never solve. Thus it leads: 1. To that one in the solution of which the latter could do nothing but commit paralogisms (namely, that of immortality), because it could not lay hold of the character of permanence, by which to complete the psychological conception of an ultimate subject necessarily ascribed to the soul in self-consciousness, so as to make it the real conception of a substance, a character which practical reason furnishes by the postulate of a duration required for accordance with the moral law in the summum bonum, which is the whole end of practical reason. 2. It leads to that of which speculative reason contained nothing but antinomy, the solution of which it could only found on a notion problematically conceivable indeed, but whose objective reality it could not prove or determine, namely, the cosmological idea of an intelligible world and the consciousness of our existence in it, by means of the postulate of freedom (the reality of which it lays down by virtue of the moral law), and with it likewise the law of an intelligible world, to which speculative reason could only point, but could not define its conception. 3. What speculative reason was able to think, but was obliged to leave undetermined as a mere transcendental ideal, viz., the theological conception of the first Being, to this it gives significance (in a practical view, that is, as a condition of the possibility of the object of a will determined by that law), namely, as the supreme principle of the summum bonum in an intelligible world, by means of moral legislation in it invested with sovereign power.

Respect for the moral law necessarily makes the summum bonum, or highest good, an object of our efforts. It also leads us to assume that the highest good has objective reality. Through the postulates of practical reason, these facts lead to concepts that speculative reason could pose as problems but could never solve. They lead to the following: 1. The first is immortality. In trying to establish immortality, speculative reason could do nothing but commit paralogisms, or errors in reasoning. Self-consciousness necessarily leads us to attribute an ultimate subject to the soul. But speculative reason could not establish that this subject is permanent. Without permanence, the psychological concept of an ultimate subject could not become a real concept of a substance. Practical reason supplies permanence through a postulate. The postulate is that the duration needed to bring us into accordance with the moral law must be possible. Such accordance belongs to the highest good, which is the whole end of practical reason. 2. The second is a problem for which speculative reason found only an antinomy, or conflict between opposing claims. Speculative reason could base a solution only on a notion it could conceive as possible. It could not prove or determine the objective reality of that notion. The notion is the cosmological idea of an intelligible world and of our awareness that we exist in it. Practical reason leads to this idea through the postulate of freedom, whose reality it affirms by virtue of the moral law. Practical reason also leads to the law of an intelligible world. Speculative reason could only point to this law. It could not define its concept. 3. The third is the theological concept of the first Being. Speculative reason could think this concept, but had to leave it undetermined as a mere transcendental ideal. Practical reason gives the concept significance from a practical point of view. The first Being becomes a condition for the possibility of the object of a will determined by the moral law. More specifically, the first Being is the supreme principle of the highest good in an intelligible world. This is so through moral legislation in that world endowed with sovereign power.

Is our knowledge, however, actually extended in this way by pure practical reason, and is that immanent in practical reason which for the speculative was only transcendent? Certainly, but only in a practical point of view. For we do not thereby take knowledge of the nature of our souls, nor of the intelligible world, nor of the Supreme Being, with respect to what they are in themselves, but we have merely combined the conceptions of them in the practical concept of the summum bonum as the object of our will, and this altogether a priori, but only by means of the moral law, and merely in reference to it, in respect of the object which it commands. But how freedom is possible, and how we are to conceive this kind of causality theoretically and positively, is not thereby discovered; but only that there is such a causality is postulated by the moral law and in its behoof. It is the same with the remaining ideas, the possibility of which no human intelligence will ever fathom, but the truth of which, on the other hand, no sophistry will ever wrest from the conviction even of the commonest man.

Does pure practical reason really extend our knowledge in this way? Does it bring within its own reach what was beyond the reach of speculative reason? Certainly, but only from a practical point of view. We do not thereby learn what our souls, the intelligible world, or the Supreme Being are in themselves. Rather, we have combined our concepts of them in the practical concept of the summum bonum, or highest good, as the object of our will. We have done this entirely a priori, but only through the moral law. We have done it solely in relation to that law and the object it commands us to pursue. But this does not reveal how freedom is possible. Nor does it reveal how we should understand this kind of causality theoretically and positively. The moral law only requires us to assume that such a causality exists, for the sake of the law. The same is true of the remaining ideas. No human intelligence will ever understand how they are possible. Yet no sophistry will ever take away even the most ordinary person's conviction that they are true.

In order not to be too abstract, we will answer this question at once in its application to the present case. In order to extend a pure cognition practically, there must be an a priori purpose given, that is, an end as object (of the will), which independently of all theological principle is presented as practically necessary by an imperative which determines the will directly (a categorical imperative), and in this case that is the summum bonum. This, however, is not possible without presupposing three theoretical conceptions (for which, because they are mere conceptions of pure reason, no corresponding intuition can be found, nor consequently by the path of theory any objective reality); namely, freedom, immortality, and God. Thus by the practical law which commands the existence of the highest good possible in a world, the possibility of those objects of pure speculative reason is postulated, and the objective reality which the latter could not assure them. By this the theoretical knowledge of pure reason does indeed obtain an accession; but it consists only in this, that those concepts which otherwise it had to look upon as problematical (merely thinkable) concepts, are now shown assertorially to be such as actually have objects; because practical reason indispensably requires their existence for the possibility of its object, the summum bonum, which practically is absolutely necessary, and this justifies theoretical reason in assuming them. But this extension of theoretical reason is no extension of speculative, that is, we cannot make any positive use of it in a theoretical point of view. For as nothing is accomplished in this by practical reason, further than that these concepts are real and actually have their (possible) objects, and nothing in the way of intuition of them is given thereby (which indeed could not be demanded), hence the admission of this reality does not render any synthetical proposition possible. Consequently, this discovery does not in the least help us to extend this knowledge of ours in a speculative point of view, although it does in respect of the practical employment of pure reason. The above three ideas of speculative reason are still in themselves not cognitions; they are however (transcendent) thoughts, in which there is nothing impossible. Now, by help of an apodeictic practical law, being necessary conditions of that which it commands to be made an object, they acquire objective reality; that is, we learn from it that they have objects, without being able to point out how the conception of them is related to an object, and this, too, is still not a cognition of these objects; for we cannot thereby form any synthetical judgement about them, nor determine their application theoretically; consequently, we can make no theoretical rational use of them at all, in which use all speculative knowledge of reason consists. Nevertheless, the theoretical knowledge, not indeed of these objects, but of reason generally, is so far enlarged by this, that by the practical postulates objects were given to those ideas, a merely problematical thought having by this means first acquired objective reality. There is therefore no extension of the knowledge of given supersensible objects, but an extension of theoretical reason and of its knowledge in respect of the supersensible generally; inasmuch as it is compelled to admit that there are such objects, although it is not able to define them more closely, so as itself to extend this knowledge of the objects (which have now been given it on practical grounds, and only for practical use). For this accession, then, pure theoretical reason, for which all those ideas are transcendent and without object, has simply to thank its practical faculty. In this they become immanent and constitutive, being the source of the possibility of realizing the necessary object of pure practical reason (the summum bonum); whereas apart from this they are transcendent, and merely regulative principles of speculative reason, which do not require it to assume a new object beyond experience, but only to bring its use in experience nearer to completeness. But when once reason is in possession of this accession, it will go to work with these ideas as speculative reason (properly only to assure the certainty of its practical use) in a negative manner: that is, not extending but clearing up its knowledge so as on one side to keep off anthropomorphism, as the source of superstition, or seeming extension of these conceptions by supposed experience; and on the other side fanaticism, which promises the same by means of supersensible intuition or feelings of the like kind. All these are hindrances to the practical use of pure reason, so that the removal of them may certainly be considered an extension of our knowledge in a practical point of view, without contradicting the admission that for speculative purposes reason has not in the least gained by this.

To avoid being too abstract, let us answer this question at once as it applies to the present case. To extend pure knowledge in practical terms, we must be given a purpose a priori. In other words, we need an end as an object of the will. This end must be presented as practically necessary by an imperative that determines the will directly. Such an imperative is categorical and does not depend on any theological principle. In this case, the end is the summum bonum, or highest good. But this is not possible without presupposing three theoretical concepts: freedom, immortality, and God. These are mere concepts of pure reason. So no corresponding intuition can be found for them, and theory cannot establish their objective reality. The practical law commands that the highest good possible in a world exist. This law therefore postulates that these objects of pure speculative reason are possible. It also postulates the objective reality that speculative reason could not establish for them. Pure reason thus gains something in theoretical knowledge. But this gain consists only in a change in the status of these concepts. Previously, theoretical reason had to regard them as problematic, as things that could merely be thought. Now they are shown as a matter of fact to have objects. Practical reason indispensably requires these objects to exist. Without them, the object of practical reason, the summum bonum, would not be possible. That object is absolutely necessary in practical terms. This justifies theoretical reason in assuming the objects of these concepts. But this extension of theoretical reason is not an extension of speculative reason. We cannot make any positive theoretical use of it. Practical reason establishes only that these concepts are real and actually have their possible objects. It gives us no intuition of them, nor could we demand one. So accepting their reality makes no synthetic proposition possible. This discovery therefore does nothing to extend our knowledge from a speculative point of view. It does, however, extend our knowledge in the practical use of pure reason. The three ideas of speculative reason are still not knowledge in themselves. They are, however, transcendent thoughts that contain nothing impossible. Now an apodeictic, or necessarily certain, practical law gives them objective reality. It does so because they are necessary conditions for what it commands us to make an object. From this law, we learn that the ideas have objects. But we cannot show how the concept of each is related to an object. Nor does this give us knowledge of these objects. We can form no synthetic judgment about them or determine their application theoretically. So we can make no theoretical use of them by reason at all. Yet all speculative knowledge of reason consists in such use. Nevertheless, theoretical knowledge is enlarged to this extent, not knowledge of these objects, but knowledge of reason generally. Through the practical postulates, objects were given to these ideas. In this way, a thought that was merely problematic first acquired objective reality. Our knowledge of given supersensible objects is therefore not extended. Rather, theoretical reason and its knowledge are extended with respect to the supersensible generally. For reason is compelled to admit that such objects exist. Yet it cannot define them more closely so as to extend its knowledge of the objects themselves. These objects have now been given to reason on practical grounds and only for practical use. Pure theoretical reason owes this gain simply to its practical faculty. For theoretical reason, all these ideas are transcendent and without objects. In practical reason, they become immanent and constitutive. They are the source of the possibility of realizing the necessary object of pure practical reason, the summum bonum. Apart from this practical use, they are transcendent and serve merely as regulative principles of speculative reason. They do not require speculative reason to assume a new object beyond experience. They require it only to bring its use within experience closer to completeness. But once reason has gained these ideas, it will deal with them as speculative reason in a negative way. Properly speaking, it will do so only to secure certainty in its practical use. It will not extend its knowledge but clarify it. On one side, it will guard against anthropomorphism, a source of superstition. Anthropomorphism also leads to an apparent extension of these concepts through supposed experience. On the other side, reason will guard against fanaticism. Fanaticism promises the same extension through supersensible intuition or similar feelings. All these are obstacles to the practical use of pure reason. Removing them may therefore be considered an extension of our knowledge from a practical point of view. This does not contradict the admission that reason has gained nothing from them for speculative purposes.

Every employment of reason in respect of an object requires pure concepts of the understanding (categories), without which no object can be conceived. These can be applied to the theoretical employment of reason, i.e., to that kind of knowledge, only in case an intuition (which is always sensible) is taken as a basis, and therefore merely in order to conceive by means of- them an object of possible experience. Now here what have to be thought by means of the categories in order to be known are ideas of reason, which cannot be given in any experience. Only we are not here concerned with the theoretical knowledge of the objects of these ideas, but only with this, whether they have objects at all. This reality is supplied by pure practical reason, and theoretical reason has nothing further to do in this but to think those objects by means of categories. This, as we have elsewhere clearly shown, can be done well enough without needing any intuition (either sensible or supersensible) because the categories have their seat and origin in the pure understanding, simply as the faculty of thought, before and independently of any intuition, and they always only signify an object in general, no matter in what way it may be given to us. Now when the categories are to be applied to these ideas, it is not possible to give them any object in intuition; but that such an object actually exists, and consequently that the category as a mere form of thought is here not empty but has significance, this is sufficiently assured them by an object which practical reason presents beyond doubt in the concept of the summum bonum, the reality of the conceptions which are required for the possibility of the summum bonum; without, however, effecting by this accession the least extension of our knowledge on theoretical principles.

Every use of reason concerning an object requires pure concepts of the understanding, or categories. Without categories, no object can be conceived. In the theoretical use of reason, that is, in knowledge, categories can be applied only when an intuition provides the basis. Intuition is always sensible. In this use, categories serve only to conceive an object of possible experience. Here, however, what must be thought through categories in order to be known are ideas of reason. These ideas cannot be given in any experience. But we are not concerned here with theoretical knowledge of the objects of these ideas. We are concerned only with whether the ideas have objects at all. Pure practical reason establishes the reality of these objects. Theoretical reason need only think them by means of categories. As we have clearly shown elsewhere, this can be done without any intuition, sensible or supersensible. Categories reside and originate in the pure understanding, simply as the faculty of thought. They do so before and independently of any intuition. They always signify only an object in general, however it may be given to us. When categories are applied to these ideas, no object can be given to them in intuition. But practical reason places an object beyond doubt in the concept of the summum bonum. This sufficiently assures the reality of the concepts required for the possibility of the summum bonum. It also assures us that such an object actually exists. Thus, the category, as a mere form of thought, is not empty here but has significance. This addition, however, does not extend our knowledge in the least on theoretical principles.

When these ideas of God, of an intelligible world (the kingdom of God), and of immortality are further determined by predicates taken from our own nature, we must not regard this determination as a sensualizing of those pure rational ideas (anthropomorphism), nor as a transcendent knowledge of supersensible objects; for these predicates are no others than understanding and will, considered too in the relation to each other in which they must be conceived in the moral law, and therefore, only so far as a pure practical use is made of them. As to all the rest that belongs to these conceptions psychologically, that is, so far as we observe these faculties of ours empirically in their exercise (e.g., that the understanding of man is discursive, and its notions therefore not intuitions but thoughts, that these follow one another in time, that his will has its satisfaction always dependent on the existence of its object, etc., which cannot be the case in the Supreme Being), from all this we abstract in that case, and then there remains of the notions by which we conceive a pure intelligence nothing more than just what is required for the possibility of conceiving a moral law. There is then a knowledge of God indeed, but only for practical purposes, and, if we attempt to extend it to a theoretical knowledge, we find an understanding that has intuitions, not thoughts, a will that is directed to objects on the existence of which its satisfaction does not in the least depend (not to mention the transcendental predicates, as, for example, a magnitude of existence, that is duration, which, however, is not in time, the only possible means we have of conceiving existence as magnitude). Now these are all attributes of which we can form no conception that would help to the knowledge of the object, and we learn from this that they can never be used for a theory of supersensible beings, so that on this side they are quite incapable of being the foundation of a speculative knowledge, and their use is limited simply to the practice of the moral law.

We further define the ideas of God, an intelligible world (the kingdom of God), and immortality using attributes drawn from our own nature. But we must not treat this as giving a sensory form to these pure ideas of reason (anthropomorphism). Nor must we treat it as transcendent knowledge of objects beyond the senses. These attributes are simply understanding and will, considered in the relation to each other required by the moral law. We use them only for purely practical purposes. We leave aside everything else that belongs to these concepts psychologically. In other words, we leave aside what we observe empirically when these faculties operate in us. For example, human understanding is discursive, so its concepts are thoughts, not intuitions, and follow one another in time. Also, the satisfaction of the human will always depends on the existence of its object. This cannot be the case in the Supreme Being. Once we set all such features aside, only one thing remains in our concepts of a pure intelligence: what is needed to conceive of a moral law. We do, then, have knowledge of God, but only for practical purposes. If we try to extend this knowledge into theoretical knowledge, we find an understanding that has intuitions, not thoughts. We also find a will directed toward objects whose existence does not at all affect its satisfaction. There are also transcendental attributes. One example is a magnitude of existence, or duration, that is not in time. Yet time is the only means we have of conceiving existence as a magnitude. None of these attributes can be conceived in a way that helps us know the object. We learn from this that they can never be used for a theory of beings beyond the senses. In this respect, they are entirely incapable of providing a foundation for speculative knowledge. Their use is limited solely to the practice of the moral law.

This last is so obvious, and can be proved so clearly by fact, that we may confidently challenge all pretended natural theologians (a singular name) * to specify (over and above the merely ontological predicates) one single attribute, whether of the understanding or of the will, determining this object of theirs, of which we could not show incontrovertibly that, if we abstract from it everything anthropomorphic, nothing would remain to us but the mere word, without our being able to connect with it the smallest notion by which we could hope for an extension of theoretical knowledge. But as to the practical, there still remains to us of the attributes of understanding and will the conception of a relation to which objective reality is given by the practical law (which determines a priori precisely this relation of the understanding to the will). When once this is done, then reality is given to the conception of the object of a will morally determined (the conception of the summum bonum), and with it to the conditions of its possibility, the ideas of God, freedom, and immortality, but always only relatively to the practice of the moral law (and not for any speculative purpose).

This last point is so obvious and can be proved so clearly by the facts that we can confidently challenge all supposed natural theologians (a curious name) *. Apart from purely ontological predicates, we challenge them to name a single attribute of understanding or will that defines their object. We could then prove beyond dispute that, if we removed everything anthropomorphic from that attribute, nothing would remain but the word itself. We could not attach even the slightest concept to it that might extend our theoretical knowledge. But in practical matters, the attributes of understanding and will still leave us with the concept of a relation. The practical law gives this relation objective reality, because it determines precisely this relation of understanding to will a priori. Once this is done, reality is given to the concept of the object of a morally determined will (the concept of the summum bonum). With that, reality is also given to the conditions that make the summum bonum possible, the ideas of God, freedom, and immortality. But this reality is always given only in relation to the practice of the moral law, not for any speculative purpose.

According to these remarks it is now easy to find the answer to the weighty question whether the notion of God is one belonging to physics (and therefore also to metaphysics, which contains the pure a priori principles of the former in their universal import) or to morals. If we have recourse to God as the Author of all things, in order to explain the arrangements of nature or its changes, this is at least not a physical explanation, and is a complete confession that our philosophy has come to an end, since we are obliged to assume something of which in itself we have otherwise no conception, in order to be able to frame a conception of the possibility of what we see before our eyes. Metaphysics, however, cannot enable us to attain by certain inference from the knowledge of this world to the conception of God and to the proof of His existence, for this reason, that in order to say that this world could be produced only by a God (according to the conception implied by this word) we should know this world as the most perfect whole possible; and for this purpose should also know all possible worlds (in order to be able to compare them with this); in other words, we should be omniscient. It is absolutely impossible, however, to know the existence of this Being from mere concepts, because every existential proposition, that is, every proposition that affirms the existence of a being of which I frame a concept, is a synthetic proposition, that is, one by which I go beyond that conception and affirm of it more than was thought in the conception itself; namely, that this concept in the understanding has an object corresponding to it outside the understanding, and this it is obviously impossible to elicit by any reasoning. There remains, therefore, only one single process possible for reason to attain this knowledge, namely, to start from the supreme principle of its pure practical use (which in every case is directed simply to the existence of something as a consequence of reason) and thus determine its object. Then its inevitable problem, namely, the necessary direction of the will to the summum bonum, discovers to us not only the necessity of assuming such a First Being in reference to the possibility of this good in the world, but, what is most remarkable, something which reason in its progress on the path of physical nature altogether failed to find, namely, an accurately defined conception of this First Being. As we can know only a small part of this world, and can still less compare it with all possible worlds, we may indeed from its order, design, and greatness, infer a wise, good, powerful, etc., Author of it, but not that He is all-wise, all-good, all-powerful, etc. It may indeed very well be granted that we should be justified in supplying this inevitable defect by a legitimate and reasonable hypothesis; namely, that when wisdom, goodness, etc, are displayed in all the parts that offer themselves to our nearer knowledge, it is just the same in all the rest, and that it would therefore be reasonable to ascribe all possible perfections to the Author of the world, but these are not strict logical inferences in which we can pride ourselves on our insight, but only permitted conclusions in which we may be indulged and which require further recommendation before we can make use of them. On the path of empirical inquiry then (physics), the conception of God remains always a conception of the perfection of the First Being not accurately enough determined to be held adequate to the conception of Deity. (With metaphysic in its transcendental part nothing whatever can be accomplished.)

These remarks make it easy to answer an important question. Does the concept of God belong to physics or to morals? It would also belong to metaphysics if it belonged to physics. For metaphysics contains the pure a priori principles of physics in their universal meaning. Suppose we appeal to God as the Author of all things to explain nature’s arrangements or changes. This is at least not a physical explanation. It is a complete admission that our philosophy has reached its limit. For we must assume something of which we otherwise have no conception in itself. Only then can we conceive how what we see before us is possible. Metaphysics cannot lead us by certain inference from knowledge of this world to the concept of God and proof of his existence. To say that only a God, as the word is understood, could have produced this world, we would need to know that it is the most perfect whole possible. We would also need to know all possible worlds so that we could compare them with this one. In other words, we would need to be omniscient. It is absolutely impossible to know that this Being exists from concepts alone. Every existential proposition affirms the existence of a being of which I have a concept. Every such proposition is synthetic. In it, I go beyond the concept and affirm more than the concept itself contains. Namely, I affirm that the concept in the understanding has a corresponding object outside the understanding. Clearly, no reasoning can draw this conclusion from the concept alone. So only one path remains for reason to attain this knowledge. It must start from the supreme principle of its pure practical use and thus determine its object. This practical use is always directed simply toward the existence of something as a consequence of reason. Reason then faces a problem it cannot avoid: the will must be directed toward the summum bonum, or highest good. This problem reveals that we must assume such a First Being for the highest good to be possible in the world. More remarkably, it also gives us something reason could not find at all by studying physical nature: a precisely defined concept of this First Being. We can know only a small part of this world, and we are even less able to compare it with all possible worlds. From its order, design, and greatness, we may indeed infer that its Author is wise, good, powerful, and so on. But we cannot infer that he is all-wise, all-good, all-powerful, and so on. We may indeed be justified in making a legitimate and reasonable hypothesis to make up for this unavoidable shortcoming. Wisdom, goodness, and other qualities appear in all the parts we can examine more closely. We may therefore reasonably suppose that they appear in the same way throughout the rest. On this basis, it would be reasonable to ascribe all possible perfections to the Author of the world. But these are not strict logical inferences in which we can take pride in our insight. They are only permissible conclusions that we may be allowed to draw. They need further support before we can use them. So, on the path of empirical inquiry, or physics, the concept of God always remains a concept of a First Being whose perfection is not defined precisely enough to be adequate to the concept of Deity. (The transcendental part of metaphysics can accomplish nothing whatever here.)

When I now try to test this conception by reference to the object of practical reason, I find that the moral principle admits as possible only the conception of an Author of the world possessed of the highest perfection. He must be omniscient, in order to know my conduct up to the inmost root of my mental state in all possible cases and into all future time; omnipotent, in order to allot to it its fitting consequences; similarly He must be omnipresent, eternal, etc. Thus the moral law, by means of the conception of the summum bonum as the object of a pure practical reason, determines the concept of the First Being as the Supreme Being; a thing which the physical (and in its higher development the metaphysical), in other words, the whole speculative course of reason, was unable to effect. The conception of God, then, is one that belongs originally not to physics, i.e., to speculative reason, but to morals. The same may be said of the other conceptions of reason of which we have treated above as postulates of it in its practical use.

When I test this conception against the object of practical reason, I find that the moral principle allows only one possibility. The author of the world must possess the highest perfection. He must be omniscient, so he can know my conduct down to the deepest roots of my mental state. He must know it in all possible cases and for all future time. He must be omnipotent, so he can assign my conduct its fitting consequences. He must also be omnipresent, eternal, and so on. Thus, the moral law determines the concept of the First Being as the Supreme Being. It does so through the conception of the summum bonum as the object of pure practical reason. The whole speculative course of reason was unable to accomplish this. It could not do so through physical reasoning, or even through its higher development, metaphysical reasoning. The conception of God, then, belongs originally not to physics, that is, to speculative reason, but to morals. The same may be said of the other conceptions of reason we discussed above as postulates of reason in its practical use.

In the history of Grecian philosophy we find no distinct traces of a pure rational theology earlier than Anaxagoras; but this is not because the older philosophers had not intelligence or penetration enough to raise themselves to it by the path of speculation, at least with the aid of a thoroughly reasonable hypothesis. What could have been easier, what more natural, than the thought which of itself occurs to everyone, to assume instead of several causes of the world, instead of an indeterminate degree of perfection, a single rational cause having all perfection? But the evils in the world seemed to them to be much too serious objections to allow them to feel themselves justified in such a hypothesis. They showed intelligence and penetration then in this very point, that they did not allow themselves to adopt it, but on the contrary looked about amongst natural causes to see if they could not find in them the qualities and power required for a First Being. But when this acute people had advanced so far in their investigations of nature as to treat even moral questions philosophically, on which other nations had never done anything but talk, then first they found a new and practical want, which did not fail to give definiteness to their conception of the First Being: and in this the speculative reason played the part of spectator, or at best had the merit of embellishing a conception that had not grown on its own ground, and of applying a series of confirmations from the study of nature now brought forward for the first time, not indeed to strengthen the authority of this conception (which was already established), but rather to make a show with a supposed discovery of theoretical reason.

In the history of Greek philosophy, we find no clear traces of a pure rational theology before Anaxagoras. But this was not because earlier philosophers lacked the intelligence or insight to reach it through speculation. They could at least have reached it with the help of a thoroughly reasonable hypothesis. What could have been easier or more natural than an idea that occurs to everyone? Instead of assuming several causes of the world, each with an indefinite degree of perfection, they could have assumed one rational cause possessing all perfection. But the evils in the world seemed to them too serious an objection to justify such a hypothesis. They showed intelligence and insight precisely by refusing to adopt it. Instead, they looked among natural causes for the qualities and power required for a First Being. But this perceptive people eventually made enough progress in studying nature to treat even moral questions philosophically. Other nations had done nothing but talk about such questions. Only then did the Greeks discover a new practical need. This need gave definite form to their conception of the First Being. Speculative reason played the part of a spectator. At best, it had the merit of embellishing a conception that had not grown from its own soil. It also brought forward, for the first time, a series of confirmations from the study of nature. These did not strengthen the authority of the conception, which was already established. Rather, they served to make a show of a supposed discovery of theoretical reason.

From these remarks, the reader of the Critique of Pure Speculative Reason will be thoroughly convinced how highly necessary that laborious deduction of the categories was, and how fruitful for theology and morals. For if, on the one hand, we place them in pure understanding, it is by this deduction alone that we can be prevented from regarding them, with Plato, as innate, and founding on them extravagant pretensions to theories of the supersensible, to which we can see no end, and by which we should make theology a magic lantern of chimeras; on the other hand, if we regard them as acquired, this deduction saves us from restricting, with Epicurus, all and every use of them, even for practical purposes, to the objects and motives of the senses. But now that the Critique has shown by that deduction, first, that they are not of empirical origin, but have their seat and source a priori in the pure understanding; secondly, that as they refer to objects in general independently of the intuition of them, hence, although they cannot effect theoretical knowledge, except in application to empirical objects, yet when applied to an object given by pure practical reason they enable us to conceive the supersensible definitely, only so far, however, as it is defined by such predicates as are necessarily connected with the pure practical purpose given a priori and with its possibility. The speculative restriction of pure reason and its practical extension bring it into that relation of equality in which reason in general can be employed suitably to its end, and this example proves better than any other that the path to wisdom, if it is to be made sure and not to be impassable or misleading, must with us men inevitably pass through science; but it is not till this is complete that we can be convinced that it leads to this goal.

These remarks will thoroughly convince readers of the Critique of Pure Speculative Reason how necessary that laborious deduction of the categories was. They will also see how fruitful it was for theology and morals. If, on the one hand, we locate the categories in pure understanding, only this deduction can keep us from treating them as innate, as Plato did. Without the deduction, we might base extravagant claims about theories of the supersensible on the categories. Such claims would have no foreseeable end, and we would turn theology into a magic lantern of fantasies. On the other hand, if we regard the categories as acquired, the deduction saves us from following Epicurus. He restricted every use of the categories, even for practical purposes, to the objects and motives of the senses. Through this deduction, the Critique has now shown, first, that the categories do not originate in experience. Rather, they belong to pure understanding and have their source there a priori. Second, the Critique has shown that the categories refer to objects in general, independently of our intuition of them. They can therefore produce theoretical knowledge only when applied to objects of experience. Yet, when applied to an object given by pure practical reason, they enable us to conceive the supersensible in a definite way. They do so, however, only insofar as the supersensible is defined by predicates necessarily connected with the pure practical purpose given a priori and with the possibility of that purpose. The speculative restriction of pure reason and its practical extension bring the two into balance. This allows reason as a whole to be used in a way suited to its purpose. This example proves better than any other that, for us humans, the path to wisdom must inevitably pass through science. Otherwise, the path cannot be made secure, and it will be impassable or misleading. But only when science is complete can we be convinced that it leads to this goal.

A want or requirement of pure reason in its speculative use leads only to a hypothesis; that of pure practical reason to a postulate; for in the former case I ascend from the result as high as I please in the series of causes, not in order to give objective reality to the result (e.g., the causal connection of things and changes in the world), but in order thoroughly to satisfy my inquiring reason in respect of it. Thus I see before me order and design in nature, and need not resort to speculation to assure myself of their reality, but to explain them I have to presuppose a Deity as their cause; and then since the inference from an effect to a definite cause is always uncertain and doubtful, especially to a cause so precise and so perfectly defined as we have to conceive in God, hence the highest degree of certainty to which this pre-supposition can be brought is that it is the most rational opinion for us men. * On the other hand, a requirement of pure practical reason is based on a duty, that of making something (the summum bonum) the object of my will so as to promote it with all my powers; in which case I must suppose its possibility and, consequently, also the conditions necessary thereto, namely, God, freedom, and immortality; since I cannot prove these by my speculative reason, although neither can I refute them. This duty is founded on something that is indeed quite independent of these suppositions and is of itself apodeictically certain, namely, the moral law; and so far it needs no further support by theoretical views as to the inner constitution of things, the secret final aim of the order of the world, or a presiding ruler thereof, in order to bind me in the most perfect manner to act in unconditional conformity to the law. But the subjective effect of this law, namely, the mental disposition conformed to it and made necessary by it, to promote the practically possible summum bonum, this pre-supposes at least that the latter is possible, for it would be practically impossible to strive after the object of a conception which at bottom was empty and had no object. Now the above-mentioned postulates concern only the physical or metaphysical conditions of the possibility of the summum bonum; in a word, those which lie in the nature of things; not, however, for the sake of an arbitrary speculative purpose, but of a practically necessary end of a pure rational will, which in this case does not choose, but obeys an inexorable command of reason, the foundation of which is objective, in the constitution of things as they must be universally judged by pure reason, and is not based on inclination; for we are in nowise justified in assuming, on account of what we wish on merely subjective grounds, that the means thereto are possible or that its object is real. This, then, is an absolutely necessary requirement, and what it pre-supposes is not merely justified as an allowable hypothesis, but as a postulate in a practical point of view; and admitting that the pure moral law inexorably binds every man as a command (not as a rule of prudence), the righteous man may say: "I will that there be a God, that my existence in this world be also an existence outside the chain of physical causes and in a pure world of the understanding, and lastly, that my duration be endless; I firmly abide by this, and will not let this faith be taken from me; for in this instance alone my interest, because I must not relax anything of it, inevitably determines my judgement, without regarding sophistries, however unable I may be to answer them or to oppose them with others more plausible. **

A need of pure reason in its speculative use leads only to a hypothesis. A need of pure practical reason leads to a postulate. In the speculative case, I go back through the series of causes as far as I please. I do not do this to establish that the effect is objectively real. One example is the causal connection among things and changes in the world. Rather, I go back through the causes to satisfy my inquiring reason fully. For example, I see order and design in nature. I do not need speculation to assure myself that they are real. But to explain them, I must suppose a Deity as their cause. An inference from an effect to a definite cause is always uncertain and doubtful. This is especially true of a cause as precise and perfectly defined as we must conceive God to be. So the greatest certainty this supposition can reach is that it is the most rational opinion for us humans. * A need of pure practical reason, on the other hand, rests on a duty. This is the duty to make something, the summum bonum (the highest good), the object of my will. I must make it my aim so that I promote it with all my powers. To do this, I must suppose that the highest good is possible. I must also suppose the conditions necessary for its possibility, namely, God, freedom, and immortality. I cannot prove these conditions by speculative reason, although I cannot refute them either. This duty rests on something entirely independent of those suppositions. That is the moral law, which is itself apodeictically certain, or certain beyond any possible doubt. In this respect, the law needs no further support to bind me completely to act in unconditional conformity with it. It needs no support from theoretical views about the inner nature of things, the hidden final purpose of the world order, or a ruler who governs it. But the law has a subjective effect. It requires me to develop a disposition in keeping with it, a disposition to promote the practically possible highest good. This disposition presupposes, at least, that the highest good is possible. It would be practically impossible to strive for the object of a concept that was empty at bottom and had no object. The postulates mentioned above concern only the physical or metaphysical conditions that make the highest good possible. In short, they concern conditions that lie in the nature of things. But their purpose is not some arbitrary speculative aim. It is an end required in practice by a pure rational will. Here, the will does not choose. It obeys an unavoidable command of reason. The foundation of this command is objective, grounded in the nature of things as pure reason must judge them universally. It is not based on inclination. We are in no way justified in assuming that the means to something are possible, or that its object is real, merely because we wish for it on subjective grounds. This requirement, then, is absolutely necessary. What it presupposes is justified not merely as an allowable hypothesis, but as a postulate from a practical point of view. If we admit that the pure moral law binds every person without exception, as a command and not as a rule of prudence, the righteous person may say: "I will that there be a God. I will that my existence in this world also be an existence outside the chain of physical causes, in a pure world of the understanding. Finally, I will that my existence be endless. I firmly hold to this, and I will not let this faith be taken from me. In this instance alone, my interest inevitably determines my judgment, because I must not relax any part of that interest. It does so regardless of sophistries, however unable I may be to answer them or oppose them with more plausible arguments. **

In order to prevent misconception in the use of a notion as yet so unusual as that of a faith of pure practical reason, let me be permitted to add one more remark. It might almost seem as if this rational faith were here announced as itself a command, namely, that we should assume the summum bonum as possible. But a faith that is commanded is nonsense. Let the preceding analysis, however, be remembered of what is required to be supposed in the conception of the summum bonum, and it will be seen that it cannot be commanded to assume this possibility, and no practical disposition of mind is required to admit it; but that speculative reason must concede it without being asked, for no one can affirm that it is impossible in itself that rational beings in the world should at the same time be worthy of happiness in conformity with the moral law and also possess this happiness proportionately. Now in respect of the first element of the summum bonum, namely, that which concerns morality, the moral law gives merely a command, and to doubt the possibility of that element would be the same as to call in question the moral law itself. But as regards the second element of that object, namely, happiness perfectly proportioned to that worthiness, it is true that there is no need of a command to admit its possibility in general, for theoretical reason has nothing to say against it; but the manner in which we have to conceive this harmony of the laws of nature with those of freedom has in it something in respect of which we have a choice, because theoretical reason decides nothing with apodeictic certainty about it, and in respect of this there may be a moral interest which turns the scale.

To prevent misunderstanding of the still unfamiliar idea of a faith of pure practical reason, let me add one more remark. It might almost seem that this rational faith is itself being commanded. That is, it might seem that we are commanded to assume that the summum bonum, or highest good, is possible. But a faith that is commanded is nonsense. Recall the preceding analysis of what must be assumed in the concept of the summum bonum. It shows that we cannot be commanded to assume that the summum bonum is possible. Nor do we need any practical disposition of mind to admit its possibility. Speculative reason must concede that possibility without being asked. No one can claim that it is impossible in itself for rational beings in the world to be worthy of happiness in accordance with the moral law and also to possess happiness in proportion to their worthiness. The first element of the summum bonum concerns morality. With respect to this element, the moral law simply gives a command. To doubt that this element is possible would be the same as questioning the moral law itself. The second element is happiness perfectly proportioned to worthiness. No command is needed to admit that this element is possible in general, since theoretical reason has nothing to say against it. But we have some choice in how we conceive the harmony between the laws of nature and those of freedom. Theoretical reason reaches no conclusion about this with absolute certainty. So a moral interest may tip the balance.

I had said above that in a mere course of nature in the world an accurate correspondence between happiness and moral worth is not to be expected and must be regarded as impossible, and that therefore the possibility of the summum bonum cannot be admitted from this side except on the supposition of a moral Author of the world. I purposely reserved the restriction of this judgement to the subjective conditions of our reason, in order not to make use of it until the manner of this belief should be defined more precisely. The fact is that the impossibility referred to is merely subjective, that is, our reason finds it impossible for it to render conceivable in the way of a mere course of nature a connection so exactly proportioned and so thoroughly adapted to an end, between two sets of events happening according to such distinct laws; although, as with everything else in nature that is adapted to an end, it cannot prove, that is, show by sufficient objective reason, that it is not possible by universal laws of nature.

I said earlier that, in the ordinary course of nature, we cannot expect happiness to correspond exactly to moral worth. Indeed, such a correspondence must be regarded as impossible. From this standpoint, then, the possibility of the summum bonum can be admitted only if we suppose a moral Author of the world. I deliberately postponed limiting this judgment to the subjective conditions of our reason. I wanted to define more precisely the kind of belief involved before making that limitation. The impossibility in question is only subjective. Our reason cannot conceive how the ordinary course of nature could produce such a connection. It cannot conceive how two sets of events governed by such different laws could be connected so precisely and so perfectly suited to a purpose. Yet, as with everything else in nature that is suited to a purpose, reason cannot prove that such a connection is impossible under universal laws of nature. In other words, it cannot give sufficient objective grounds for ruling out that possibility.

Now, however, a deciding principle of a different kind comes into play to turn the scale in this uncertainty of speculative reason. The command to promote the summum bonum is established on an objective basis (in practical reason); the possibility of the same in general is likewise established on an objective basis (in theoretical reason, which has nothing to say against it). But reason cannot decide objectively in what way we are to conceive this possibility; whether by universal laws of nature without a wise Author presiding over nature, or only on supposition of such an Author. Now here there comes in a subjective condition of reason, the only way theoretically possible for it, of conceiving the exact harmony of the kingdom of nature with the kingdom of morals, which is the condition of the possibility of the summum bonum; and at the same time the only one conducive to morality (which depends on an objective law of reason). Now since the promotion of this summum bonum, and therefore the supposition of its possibility, are objectively necessary (though only as a result of practical reason), while at the same time the manner in which we would conceive it rests with our own choice, and in this choice a free interest of pure practical reason decides for the assumption of a wise Author of the world; it is clear that the principle that herein determines our judgement, though as a want it is subjective, yet at the same time being the means of promoting what is objectively (practically) necessary, is the foundation of a maxim of belief in a moral point of view, that is, a faith of pure practical reason. This, then, is not commanded, but being a voluntary determination of our judgement, conducive to the moral (commanded) purpose, and moreover harmonizing with the theoretical requirement of reason, to assume that existence and to make it the foundation of our further employment of reason, it has itself sprung from the moral disposition of mind; it may therefore at times waver even in the well-disposed, but can never be reduced to unbelief.

Now, however, a different kind of principle comes into play. It resolves this uncertainty of speculative reason. The command to promote the summum bonum, or highest good, has an objective basis in practical reason. The possibility of the highest good in general also has an objective basis. Theoretical reason has nothing to say against that possibility. But reason cannot objectively decide how we should conceive of this possibility. It cannot decide whether the highest good is possible through universal laws of nature without a wise Author presiding over nature, or only if such an Author exists. At this point, a subjective condition of reason comes into play. Reason can conceive of the exact harmony between the kingdom of nature and the kingdom of morals in only one theoretically possible way. That harmony is the condition for the possibility of the highest good. This way of conceiving it is also the only one that promotes morality, which depends on an objective law of reason. Promoting the highest good is objectively necessary, though only as a result of practical reason. So we must also suppose that the highest good is possible. Yet how we conceive of that possibility is a matter of choice. In making that choice, a free interest of pure practical reason decides in favor of assuming a wise Author of the world. The principle that determines our judgment here is subjective, since it rests on a need. Yet it also serves to promote what is objectively necessary in practical terms. It is therefore the basis for a maxim of belief from a moral point of view. In other words, it is the basis for a faith of pure practical reason. This faith, then, is not commanded. Rather, we voluntarily decide to assume that a wise Author exists and to make that assumption the basis for our further use of reason. This decision promotes the moral purpose we are commanded to pursue, and it also accords with the theoretical requirement of reason. The decision itself arises from a moral disposition of mind. It may therefore sometimes waver, even in people of good moral disposition, but it can never give way to unbelief.

If human nature is destined to endeavour after the summum bonum, we must suppose also that the measure of its cognitive faculties, and particularly their relation to one another, is suitable to this end. Now the Critique of Pure Speculative Reason proves that this is incapable of solving satisfactorily the most weighty problems that are proposed to it, although it does not ignore the natural and important hints received from the same reason, nor the great steps that it can make to approach to this great goal that is set before it, which, however, it can never reach of itself, even with the help of the greatest knowledge of nature. Nature then seems here to have provided us only in a step-motherly fashion with the faculty required for our end.

If human nature is destined to pursue the summum bonum, or highest good, our capacities for knowledge must be suited to that end. In particular, the way those capacities relate to one another must be suited to it. But the Critique of Pure Speculative Reason proves that speculative reason cannot satisfactorily solve the most important problems it faces. The Critique does not ignore the natural and important hints that reason itself provides. Nor does it ignore the great steps reason can take toward the great goal set before it. Yet reason can never reach that goal on its own, even with the greatest knowledge of nature. Nature therefore seems to have given us less than a mother's care in providing the capacity needed for our end.

Suppose, now, that in this matter nature had conformed to our wish and had given us that capacity of discernment or that enlightenment which we would gladly possess, or which some imagine they actually possess, what would in all probability be the consequence? Unless our whole nature were at the same time changed, our inclinations, which always have the first word, would first of all demand their own satisfaction, and, joined with rational reflection, the greatest possible and most lasting satisfaction, under the name of happiness; the moral law would afterwards speak, in order to keep them within their proper bounds, and even to subject them all to a higher end, which has no regard to inclination. But instead of the conflict that the moral disposition has now to carry on with the inclinations, in which, though after some defeats, moral strength of mind may be gradually acquired, God and eternity with their awful majesty would stand unceasingly before our eyes (for what we can prove perfectly is to us as certain as that of which we are assured by the sight of our eyes). Transgression of the law, would, no doubt, be avoided; what is commanded would be done; but the mental disposition, from which actions ought to proceed, cannot be infused by any command, and in this case the spur of action is ever active and external, so that reason has no need to exert itself in order to gather strength to resist the inclinations by a lively representation of the dignity of the law: hence most of the actions that conformed to the law would be done from fear, a few only from hope, and none at all from duty, and the moral worth of actions, on which alone in the eyes of supreme wisdom the worth of the person and even that of the world depends, would cease to exist. As long as the nature of man remains what it is, his conduct would thus be changed into mere mechanism, in which, as in a puppet-show, everything would gesticulate well, but there would be no life in the figures. Now, when it is quite otherwise with us, when with all the effort of our reason we have only a very obscure and doubtful view into the future, when the Governor of the world allows us only to conjecture his existence and his majesty, not to behold them or prove them clearly; and on the other hand, the moral law within us, without promising or threatening anything with certainty, demands of us disinterested respect; and only when this respect has become active and dominant, does it allow us by means of it a prospect into the world of the supersensible, and then only with weak glances: all this being so, there is room for true moral disposition, immediately devoted to the law, and a rational creature can become worthy of sharing in the summum bonum that corresponds to the worth of his person and not merely to his actions. Thus what the study of nature and of man teaches us sufficiently elsewhere may well be true here also; that the unsearchable wisdom by which we exist is not less worthy of admiration in what it has denied than in what it has granted.

Suppose nature had granted our wish in this matter. Suppose it had given us the discernment or enlightenment we would gladly possess, or that some imagine they already possess. What would probably follow? Unless our whole nature also changed, our inclinations would still speak first. They would demand satisfaction, and, with the help of rational reflection, the greatest and most lasting satisfaction possible, under the name of happiness. The moral law would then speak to keep those inclinations within their proper bounds. It would even subject them all to a higher end that takes no account of inclination. But now our moral disposition must struggle with our inclinations. In that struggle, we may gradually gain moral strength of mind, even after some defeats. Instead, God and eternity, in their awe-inspiring majesty, would stand constantly before our eyes. For what we can prove completely is as certain to us as what we see with our own eyes. We would no doubt avoid breaking the law and do what it commands. But no command can instill the disposition from which actions ought to arise. In this case, the spur to action would always be present and external. Reason would have no need to call up a vivid sense of the law’s dignity. It would not need to do so to gather strength to resist our inclinations. Most actions that conformed to the law would therefore be done from fear, a few from hope, and none from duty. The moral worth of actions would cease to exist. Yet in the eyes of supreme wisdom, the worth of the person, and even of the world, depends on that moral worth alone. As long as human nature remains what it is, human conduct would become a mere mechanism. As in a puppet show, everything would move as it should, but there would be no life in the figures. But our situation is quite different. With all the effort of our reason, we have only a very obscure and doubtful view of the future. The Governor of the world allows us only to conjecture his existence and majesty, not to behold them or prove them clearly. The moral law within us, on the other hand, demands selfless respect without any certain promise or threat. Only when this respect has become active and dominant does the moral law, through that respect, allow us a view into the supersensible world. Even then, it allows us only faint glimpses. Under these conditions, there is room for a true moral disposition, devoted directly to the law. A rational being can become worthy of sharing in the summum bonum, in keeping with the worth of the person, not merely the person’s actions. The study of nature and humanity teaches us a lesson clearly enough elsewhere, and it may well hold here too. The unfathomable wisdom through which we exist is no less worthy of admiration for what it has denied us than for what it has granted us.