Book I: Critical examination of the analytic of pure practical reason

Critical Examination of the Analytic of Pure Practical Reason

By the critical examination of a science, or of a section of it that forms a system in its own right, I mean the investigation and justification of why it must have precisely this systematic form and no other, when compared with another system grounded in a similar cognitive faculty. Now practical reason rests on the same cognitive faculty as speculative reason insofar as both are pure reason. The difference between their systematic forms must therefore be determined by comparing them, and its ground must be given.

The Analytic of pure theoretical reason dealt with the cognition of objects that may be given to the understanding, A 160 and therefore had to begin with intuition, hence with sensibility (since intuition is always sensible); only from there could it advance to concepts (of the objects of this intuition), and only after both had been presented could it end with principles. Practical reason, by contrast, deals not with objects in order to cognize them, but with its own capacity to make them actual (in accordance with cognition of them): that is, with a will, which is a causality insofar as reason contains its determining ground. Consequently, it has no object of intuition to specify, but, as practical reason, only a law of that causality (since the concept of causality always involves reference to a law determining the existence of a manifold in its mutual relations). A critique of its analytic must therefore, insofar as it is to be practical reason—which is the task proper—begin with the possibility of practical V:90 principles a priori. Only from there could it advance to concepts of the objects of practical reason, namely those of the unconditionally good and evil, in order first to supply them in accordance with those principles (for before these principles no cognitive faculty can supply these objects as good and evil). Only then could the final chapter, on the A 161 relation of pure practical reason to sensibility and its necessary influence on sensibility, which can be cognized a priori—that is, on moral feeling—bring the section to a close. Thus the Analytic of pure practical reason divided the whole range of conditions of its use in complete analogy with theoretical reason, but in reverse order. The Analytic of pure theoretical reason was divided into transcendental aesthetic and transcendental logic; that of practical reason, conversely, into the logic and aesthetic of pure practical reason (if I may employ these otherwise quite inappropriate names here merely for the sake of analogy). Logic, in turn, was divided there into the analytic of concepts and that of principles, and here into that of principles and concepts. There the aesthetic had two further parts, because sensible intuition is of two kinds; here sensibility is considered not at all as a capacity for intuition, but merely as feeling (which can be a subjective ground of desire), and in this respect pure practical reason permits no further division.

It is also quite easy to see why this division into two parts, with their subdivisions, was not actually carried out here—as the example of the former might initially have tempted one to attempt. For since it is pure reason A 162 that is considered here in its practical use, thus proceeding from principles a priori and not from empirical determining grounds, the division of the Analytic of pure practical reason must resemble that of a syllogism. It proceeds from the universal in the major premise (the moral principle), through the subsumption of possible actions (as good or evil) under it in the minor premise, to the conclusion: the subjective determination of the will (an interest in the practically possible good and the maxim grounded on it). Anyone who has been V:91 convinced by the propositions presented in the Analytic will take pleasure in such comparisons. For they rightly encourage the hope that we may perhaps someday attain insight into the unity of the entire faculty of pure reason, theoretical as well as practical, and derive everything from one principle. This is the unavoidable need of human reason, which finds complete satisfaction only in a fully systematic unity of its cognitions.

But if we also consider the content of the cognition that we can have of and through pure practical reason, as its Analytic presents it, we find differences no less remarkable than the analogy between it and theoretical reason. In the case of theoretical reason, the capacity A 163 for pure rational cognition a priori could be proved quite easily and evidently through examples drawn from the sciences. Since they test their principles in so many ways through methodical use, there is less reason here than in ordinary cognition to fear a hidden admixture of empirical grounds of cognition. But that pure reason, without any admixture of an empirical determining ground, is also practical on its own had to be demonstrable from the most ordinary practical use of reason. This required establishing the supreme practical principle as one that every natural human reason recognizes as entirely a priori, independent of all sensible data, and as the supreme law of its will. The purity of its origin first had to be confirmed and justified even in the judgment of this ordinary reason, before science could take it in hand and make use of it—as a fact, so to speak, that precedes all quibbling about its possibility and all consequences that might be drawn from it. But this circumstance too is readily explained by what was said just above: pure practical reason must necessarily begin with principles, which must therefore underlie all science as its first data and cannot first A 164 arise from it. This justification of moral principles as principles of pure reason could also be carried out quite satisfactorily and with sufficient certainty by appealing solely to the judgment of ordinary human understanding. For everything empirical that might steal into our V:92 maxims as a determining ground of the will immediately reveals itself through the feeling of pleasure or pain that necessarily accompanies it insofar as it arouses desire; and pure practical reason directly resists admitting this feeling into its principle as a condition. The heterogeneity of the determining grounds, empirical and rational, is made recognizable through this resistance of practically legislative reason to every interfering inclination, through a distinctive kind of sensation. This sensation does not precede practical reason's legislation, but is produced solely by it, and indeed as a constraint: it is the feeling of respect, such as no human being has for inclinations, whatever their kind, but does have for the law. This renders that heterogeneity so clear, so prominent and striking, that no one, not even the most ordinary human understanding, could fail to recognize at once, in an example presented to it, that empirical grounds of willing may indeed advise it to follow their attractions, A 165 but can never demand that it obey anything other than the pure practical law of reason alone.

Distinguishing the doctrine of happiness from the doctrine of morals—in the former empirical principles constitute the entire foundation, while in the latter they form not even the slightest addition—is therefore the first and most important business incumbent on the Analytic of pure practical reason. In this it must proceed as precisely, indeed, even at the risk of being called painstaking, as any geometer in his work. Yet the philosopher, who here faces greater difficulty—as always in rational cognition through mere concepts without their construction—because he cannot take any intuition of a pure noumenon as his basis, also enjoys an advantage: almost like the chemist, he can at any time perform an experiment with anyone's practical reason to distinguish the moral (pure) determining ground from the empirical. He need only add the moral law, as a determining ground, to the empirically affected will—for example, that of someone who would like to lie because he can gain something by it. It is as though the chemist added alkali to a solution of calcareous earth in hydrochloric acid: the acid immediately leaves the lime, combines with the alkali, and the lime precipitates. Just so, A 166 present the moral V:93 law to someone who is otherwise an honest person—or who, for this occasion, merely imagines himself in an honest person's place—and he recognizes by it the worthlessness of a liar. His practical reason immediately abandons advantage in its judgment of what he ought to do and unites with what preserves his respect for his own person: truthfulness. Once advantage has been separated and washed free of every attachment to reason, which is entirely on the side of duty, anyone can then weigh it, so that it may indeed enter into combination with reason in other cases, but never where it could conflict with the moral law, which reason never abandons but unites with most intimately.

But this distinction between the principle of happiness and that of morality does not at once make them opposites. Pure practical reason does not require us to give up our claims to happiness, but only to disregard them altogether whenever duty is at issue. In a certain respect, it can even be a duty to attend to one's happiness: partly because it includes means for fulfilling one's duty, among them skill, health, and wealth; partly because its absence—poverty, for example—contains temptations A 167 to transgress one's duty. But promoting one's happiness can never be a duty directly, still less a principle of all duty. Now all determining grounds of the will apart from the single pure practical law of reason, the moral law, are empirical without exception, and as such belong to the principle of happiness. They must therefore all be separated from the supreme moral principle and never incorporated into it as a condition, because doing so would destroy all moral worth, just as an empirical admixture in geometrical principles would destroy all mathematical evidence—the most excellent quality mathematics possesses, in Plato's judgment, and one that takes precedence even over all its usefulness.

In place of a deduction of the supreme principle of pure practical reason—that is, an explanation of the possibility of such cognition a priori—nothing further could be offered than this: if we understood the possibility of the freedom of an efficient cause, we would also understand not merely the possibility but the necessity of the moral law as the supreme practical law of rational beings to whom we attribute freedom in the causality of their will. For the two concepts are so inseparably connected that practical V:94 freedom could also be defined as the will's independence of every law other than A 168 the moral law alone. Yet how the freedom of an efficient cause is possible, especially in the sensible world, cannot by any means be understood. We are fortunate if we can merely be sufficiently assured that no proof of its impossibility is available, and then, compelled by the moral law that postulates it, are thereby also entitled to assume it. Many, however, still believe that they can explain this freedom from empirical principles, like any other natural capacity. They regard it as a psychological property, whose explanation would depend solely on a closer investigation of the nature of the soul and the incentive of the will, rather than as a transcendental predicate of the causality of a being belonging to the sensible world—which is really the sole issue here. In this way they annul the magnificent disclosure granted us by pure practical reason through the moral law: the disclosure of an intelligible world by giving reality to the otherwise transcendent concept of freedom. They thereby annul the moral law itself, which admits absolutely no empirical determining ground. It will therefore be necessary to add something here to guard against this illusion and expose empiricism in the full nakedness of its shallowness.

The concept of causality as natural necessity, in distinction A 169 from causality as freedom, concerns only the existence of things insofar as it is determinable in time, hence as appearances, in contrast with their causality as things in themselves. Now if we take the determinations of the existence of things in time to be determinations of things in themselves, as our most usual way of representing them does, necessity in causal relations cannot in any way be reconciled with freedom; rather, they stand in contradictory opposition. For the former entails that every event, and thus every action occurring at a point in time, is necessary under the condition of what existed in the preceding time. Since past time is no longer within my power, every action I perform must be necessary through determining grounds that are not within my power: that is, at the moment when I act, I am never free. Indeed, even if I assumed my entire existence to be independent of any external cause—God, for example—V:95 so that the determining grounds of my causality, and even of my entire existence, were not outside me at all, this would still not in the least transform that natural necessity into freedom. For at every point in time I always remain subject to the necessity of being determined to act by what is not within my power. A 170 The series of events, infinite toward the past, which I would only ever continue according to an already predetermined order and would nowhere begin of myself, would be an unbroken chain of nature; my causality would therefore never be freedom.

If, then, we wish to attribute freedom to a being whose existence is determined in time, we cannot, at least in this respect, exempt it from the law of natural necessity governing all events in its existence, and thus also its actions; that would amount to handing it over to blind chance. But since this law inevitably concerns all causality of things insofar as their existence is determinable in time, freedom would have to be rejected as an empty and impossible concept if this were also the way we had to represent the existence of these things in themselves. Consequently, if we still wish to save freedom, no course remains but to attribute a thing's existence insofar as it is determinable in time, and thus also its causality according to the law of natural necessity, solely to appearance, while attributing freedom to the very same being as a thing in itself. This is certainly unavoidable if we wish to preserve both these mutually opposed concepts together. Yet in applying them, when we wish to regard them as united in one and the same action A 171 and thus to explain this union itself, great difficulties emerge that seem to make such a union unworkable.

If I say of someone who commits a theft that, under the natural law of causality, this deed is a necessary consequence of the determining grounds of the preceding time, then it was impossible for it not to occur. How, then, can judgment according to the moral law alter anything here and presuppose that it could nevertheless have been left undone, because the law says that it ought to have been left undone? That is, how can someone be called entirely free at the very same point in time, and with regard to the very same action, at which, and with regard to which, he nevertheless stands under an unavoidable V:96 natural necessity? To seek an escape by merely adapting the kind of determining grounds of his causality under natural law to a comparative concept of freedom is a miserable expedient. According to this concept, an effect is sometimes called free when its determining natural ground lies within the acting being: for example, what a thrown body does in free motion, where the word freedom is used because, while in flight, it is not driven by anything external; or as we also call a clock's motion free because it drives its own hand, which therefore need not be pushed A 172 from outside. In the same way, human actions, though necessary through their determining grounds preceding them in time, are still called free because they involve internal representations produced by our own powers, desires generated through these according to the circumstances that occasion them, and hence actions effected at our own discretion. Some still let themselves be put off with this expedient and think they have solved by a little verbal quibbling that difficult problem on which millennia have labored in vain—a solution therefore hardly likely to lie so entirely on the surface. For in the question of the freedom that must underlie all moral laws and the imputation appropriate to them, it does not matter at all whether causality determined according to a natural law is necessitated by determining grounds that lie within or outside the subject, or, in the former case, whether by instinct or by determining grounds thought through reason. If, as these very men themselves concede, these determining representations still have the ground of their existence in time, specifically in the previous state, and that state in another preceding it, and so on, then these determinations may indeed be internal; they may have psychological rather than mechanical causality A 173—that is, produce action through representations rather than through bodily motion. Yet they remain determining grounds of the causality of a being insofar as its existence is determinable in time, hence under necessitating conditions of past time that are therefore no longer within its power when the subject is to act. These conditions may indeed involve psychological freedom, if one insists on using this word for a merely internal linkage of the soul's representations; but they still involve natural necessity and thus leave no transcendental V:97 freedom. This freedom must be thought as independence of everything empirical, and thus of nature in general, whether nature is considered as an object of inner sense merely in time or also of outer sense in both space and time. Without freedom in this latter, proper meaning, which alone is practical a priori, no moral law and no imputation according to it are possible. For precisely this reason, all necessity of events in time under the natural law of causality can also be called the mechanism of nature, although this does not mean that the things subject to it must be actual material machines. Only the necessity of the connection of events in a temporal series, as it unfolds according to natural law, is considered here. The subject in which this A 174 course of events takes place may be called an automaton materiale, if its machinery is driven by matter, or, with Leibniz, spirituale, if it is driven by representations. And if the freedom of our will were nothing other than the latter—say, psychological and comparative, not at the same time transcendental, that is, absolute—then at bottom it would be no better than the freedom of a roasting spit, which also performs its motions by itself once it has been wound up.

To resolve, in the case presented, the apparent contradiction between natural mechanism and freedom in one and the same action, we must recall what was said in the Critique of Pure Reason, or follows from it: natural necessity, which cannot coexist with the subject's freedom, attaches solely to the determinations of a thing that stands under temporal conditions, hence only to those of the acting subject as appearance. In this respect, therefore, the determining grounds of each of its actions lie in what belongs to past time and is no longer within its power. This must also include its deeds already committed and the character thereby determinable for it in its own eyes as a phenomenon. But the very same subject, A 175 which is also conscious of itself on the other hand as a thing in itself, considers its existence insofar as it does not stand under temporal conditions, and itself as determinable only through laws that it gives itself through reason. In this existence of its own, nothing precedes its determination of the will. Rather, every action and, in general, V:98 every determination of its existence that changes in accordance with inner sense—even the entire sequence of its existence as a sensible being—is, in the consciousness of its intelligible existence, to be regarded solely as a consequence, never as a determining ground of its causality as a noumenon. In this respect, a rational being can rightly say of every unlawful action it commits that it could have left it undone, even though as appearance the action is sufficiently determined in the past and to that extent is unavoidably necessary. For the action, together with everything past that determines it, belongs to a single phenomenon of its character, which it supplies for itself, and in accordance with which it imputes to itself, as a cause independent of all sensibility, the causality of those appearances.

The verdicts of that wondrous faculty within us which we call conscience agree perfectly with this. A person may use all the ingenuity he pleases to portray to himself some unlawful conduct A 176 he remembers as an unintentional oversight, a mere carelessness that can never be entirely avoided, and thus as something in which he was swept along by the current of natural necessity, and on this basis declare himself free of guilt. Yet he finds that the advocate speaking in his favor can by no means silence the accuser within him if he is conscious that, at the time he committed the wrong, he was in possession of his senses—that is, exercising his freedom. And although he explains his offense to himself from some bad habit acquired through gradually neglecting attention to himself, to the point that he can regard it as a natural consequence of that habit, this still cannot protect him against the self-reproach and rebuke he directs at himself. On this too rests remorse for a deed long since committed, whenever it is remembered: a painful sensation produced by a moral disposition, practically empty insofar as it cannot serve to undo what has been done. It would even be absurd—as Priestley, a genuine and consistent fatalist, also declares it to be. For this candor he deserves more approval than those who, while in fact asserting the mechanism of the will and affirming its freedom only in A 177 words, still wish to be credited—without making the possibility of such imputation intelligible—V:99 with including freedom in their syncretistic system. Yet as pain it is entirely justified, because reason, when the law of our intelligible existence—the moral law—is at issue, recognizes no distinction of time and asks only whether the event belongs to me as my deed. It then always morally connects the same sensation with it, whether it is happening now or happened long ago. For sensible life, in relation to the intelligible consciousness of its existence (freedom), has the absolute unity of a phenomenon. Insofar as this phenomenon contains merely appearances of the disposition with which the moral law is concerned—of character—it must be judged not according to the natural necessity that belongs to it as appearance, but according to the absolute spontaneity of freedom. We may therefore grant that, if we could gain so deep an insight into a person's way of thinking, as manifested in both inner and outer actions, that we knew every incentive to these actions, even the slightest, and likewise every external occasion acting upon them, we could calculate that person's future conduct with as much certainty as a lunar or solar eclipse, and nevertheless maintain that the person A 178 is free. For if we were capable of yet another view, namely an intellectual intuition of the same subject—a view certainly not granted to us, in place of which we have only the concept supplied by reason—we would recognize that this entire chain of appearances, with regard to everything that can in any way concern the moral law, depends on the spontaneity of the subject as a thing in itself, whose determination admits of no physical explanation whatever. In the absence of this intuition, the moral law assures us of the distinction between the relation of our actions as appearances to the sensible being of our subject and the relation through which this sensible being itself is referred to the intelligible substratum within us.—From this standpoint, which is natural to our reason though inexplicable, we can also justify judgments that, although passed with complete conscientiousness, nevertheless seem at first sight to contradict all fairness. There are cases in which people show such early wickedness, from childhood onward, even under an upbringing that has benefited others alongside them, and continue to advance in it so far into adulthood, that they are considered born villains and, in their way of thinking, wholly incorrigible. V:100 Yet they are judged for their acts and omissions just like anyone else; A 179 their crimes are reproached to them as guilt, and they themselves—even as children—find these reproaches entirely well grounded, as though, despite the hopeless natural constitution of mind attributed to them, they remained as responsible as every other human being. This could not happen unless we presupposed that everything arising from their power of choice—as every intentionally committed action undoubtedly does—rests on a free causality. From earliest youth this causality expresses its character in its appearances, its actions, which reveal through the uniformity of conduct a natural connection. But this connection does not necessitate the bad constitution of the will; it is rather the consequence of freely adopted evil and unalterable principles, which make the person only all the more reprehensible and deserving of punishment.

But freedom faces yet another difficulty insofar as it is to be united with natural mechanism in a being belonging to the sensible world—a difficulty that, even after everything so far has been conceded, still threatens freedom with complete destruction. Yet amid this danger one circumstance also offers hope of an outcome favorable to the assertion of freedom: the same difficulty weighs far more heavily—in A 180 fact, as we shall soon see, exclusively—upon the system in which existence determinable in time and space is taken to be the existence of things in themselves. It therefore does not compel us to abandon our principal presupposition of the ideality of time as a mere form of sensible intuition, hence as a mere way of representing that is peculiar to the subject as belonging to the sensible world. It requires only that we reconcile the difficulty with this idea.

For even if we are granted that the intelligible subject can still be free with regard to a given action, although as a subject also belonging to the sensible world it is mechanically conditioned with regard to that action, it nevertheless seems that we must concede something further as soon as we assume that God, as the universal original being, is also the cause of the existence of substance. This proposition can never be abandoned without also abandoning the concept of God as the being of all beings, and hence his all-sufficiency, on which everything in theology depends. It seems we must then concede that human actions have their determining ground in V:101 something entirely beyond human power: namely, in the causality of a supreme being distinct from the human being, on whom the latter's existence and the entire determination of his causality wholly depend. Indeed, if A 181 human actions, insofar as they belong to a person's determinations in time, were not mere determinations of that person as appearance but as a thing in itself, freedom could not be saved. A human being would be a marionette, or a Vaucanson automaton, built and wound up by the supreme master of all works of art. Self-consciousness would indeed make it a thinking automaton, but the consciousness of its spontaneity, if taken for freedom, would be mere deception. For this spontaneity would deserve that name only comparatively: the immediate determining causes of its motion, and a long series ascending to their determining causes, would indeed be internal, but the final and highest cause would still be found entirely in another's hands. I therefore do not see how those who still insist on regarding time and space as determinations belonging to the existence of things in themselves intend to avoid the fatal necessity of actions here. Nor, if they simply concede—as the otherwise penetrating Mendelssohn did—that the two are conditions necessarily belonging only to the existence of finite and derivative beings, but not to that of the infinite original being, do I see how they intend to justify their authority to make such a distinction. I do not even see how they can avoid the contradiction A 182 they commit when they regard existence in time as a determination necessarily attaching to finite things in themselves: God is the cause of this existence, yet cannot be the cause of time or space itself, because these must be presupposed a priori as necessary conditions of the existence of things. His causality with respect to the existence of these things must consequently itself be conditioned by time, whereupon all the contradictions with the concepts of his infinity and independence must inevitably arise. By contrast, it is quite easy for us to distinguish the determination of divine existence as independent of all temporal conditions from that of a being of the sensible world, as the existence of a being in itself from that of a thing in appearance. Hence, unless we accept this ideality of time and space, V:102 Spinozism alone remains. In it, space and time are essential determinations of the original being itself, while the things dependent on it—and thus we ourselves as well—are not substances but merely accidents inhering in it. For if these things exist merely as its effects in time, which would be the condition of their existence in themselves, then the actions of these beings too would have to be merely its actions, performed somewhere and sometime. Despite the absurdity of its fundamental idea, A 183 Spinozism therefore argues far more conclusively than the theory of creation can when it regards beings assumed to be substances and existing in themselves in time as effects of a supreme cause, yet not at the same time as belonging to that cause and its action, but as substances in their own right.

The difficulty mentioned above is resolved briefly and clearly as follows. If existence in time is merely a sensible way in which thinking beings in the world represent existence, and consequently does not concern them as things in themselves, then the creation of these beings is a creation of things in themselves. For the concept of creation does not belong to the sensible way of representing existence and causality, but can be referred only to noumena. Consequently, when I say of beings in the sensible world that they are created, I consider them in that respect as noumena. Just as it would therefore be a contradiction to say that God is a creator of appearances, so it is also a contradiction to say that, as creator, he is the cause of actions in the sensible world, hence as appearances, although he is the cause of the existence of the acting beings as noumena. Now if it is possible to maintain freedom without prejudice to the natural mechanism A 184 of actions as appearances—provided we take existence in time to hold merely of appearances, not of things in themselves—then the fact that the acting beings are creatures cannot make the slightest difference here. For creation concerns their intelligible, not their sensible existence, and thus cannot be regarded as a determining ground of appearances. But the outcome would be entirely different if beings in the world existed as things in themselves in time, since the creator of the substance would then also be the author of the entire mechanism in that substance.

Such is the great importance of separating time, as well as space, from the existence of things in themselves, as accomplished in the Critique of Pure Speculative V:103 Reason.

But, it will be said, the resolution of the difficulty presented here still contains much that is difficult and scarcely admits of a lucid exposition. Yet is any other resolution that has been attempted, or might be attempted, easier and more comprehensible? One might rather say that the dogmatic teachers of metaphysics showed more cunning than sincerity in keeping this difficult point out of sight as far as possible, in the hope that, if they said nothing about it, no one else would readily think of it either. If a science is to be helped, all its difficulties must be exposed, and even those that stand most secretly A 185 in its way must be sought out. For each calls forth a remedy that cannot be found without providing the science with an increase either in scope or in precision; thus even the obstacles become means of advancing the science's thoroughness. By contrast, if difficulties are deliberately concealed or removed only by palliatives, sooner or later they break out into incurable evils that destroy the science in a complete skepticism.

Since it is really the concept of freedom alone, among all the ideas of pure speculative reason, that affords so great an extension in the field of the supersensible, though only with respect to practical cognition, I ask myself: why has it alone been endowed with such great fruitfulness, while the other ideas merely indicate the vacant place for possible pure beings of the understanding, but cannot determine their concept in any way? I soon realize that, since I can think nothing without a category, the category must first be sought out in the rational idea of freedom with which I am occupied; here it is the category of causality. And although no corresponding intuition can be supplied A 186 for the rational concept of freedom, as a concept that transcends experience, a sensible intuition must nevertheless first be given for the concept of the understanding—causality—for whose synthesis that rational concept demands the unconditioned. Through this intuition its objective reality V:104 is first secured. Now all categories are divided into two classes: the mathematical, which concern merely the unity of synthesis in the representation of objects, and the dynamical, which concern that unity in the representation of the existence of objects. The former, those of magnitude and quality, always contain a synthesis of the homogeneous. In this synthesis, the unconditioned for the conditioned given in sensible intuition in space and time can never be found, since it would itself have to belong to space and time and thus always be conditioned in turn. Hence in the Dialectic of pure theoretical reason, the two opposed ways of finding the unconditioned and the totality of conditions for these categories were both false. The categories of the second class, those of causality and of the necessity of a thing, did not require this homogeneity of the conditioned and the condition in the synthesis at all. For what had to be represented here was not how intuition is composed of a manifold within it, but only how the existence of the conditioned object corresponding to it is added to the existence of the condition, as connected with it in the understanding. A 187 Here it was permissible to place the unconditioned, though otherwise undetermined, in the intelligible world as the condition of what is thoroughly conditioned in the sensible world—both with regard to causality and to the contingent existence of things themselves—and to make the synthesis transcendent. Hence the Dialectic of pure speculative reason also found that the two seemingly opposed ways of finding the unconditioned for the conditioned did not in fact contradict one another. For example, in the synthesis of causality, we may think, for what is conditioned in the series of causes and effects of the sensible world, a causality that is not itself sensibly conditioned. The same action, which as belonging to the sensible world is always sensibly conditioned—that is, mechanically necessary—may nevertheless also, as belonging to the causality of the acting being insofar as it belongs to the intelligible world, rest on a sensibly unconditioned causality, and thus be thought as free. All that remained was to transform this could be into an is: that is, in an actual case, to prove, as though by a fact, that certain actions presuppose such a causality—an intellectual, sensibly unconditioned causality—whether these actions are actual or merely commanded, that is, objectively practically necessary. We could not hope to encounter A 188 V:105 this connection in actions actually given in experience as events in the sensible world, because causality through freedom must always be sought outside the sensible world, in the intelligible. Yet no things other than sensible beings are given to us for perception and observation. Nothing therefore remained but perhaps to find an incontestable and indeed objective principle of causality that excludes every sensible condition from its determination: a principle in which reason does not appeal to anything else as a determining ground with regard to causality, but already contains that ground itself through this principle, and in which it is thus itself practical as pure reason. This principle, however, needs neither searching out nor invention. It has long been present in the reason of all human beings and incorporated into their very being: it is the principle of morality. Thus that unconditioned causality and the capacity for it, freedom, and with freedom a being—myself—that belongs to the sensible world yet also to the intelligible world, are not merely thought indeterminately and problematically, as speculative reason could already establish was possible. They are even, with respect to the law of their causality, determined and assertorically cognized. In this way the actuality of the intelligible world is given to us, and given determinately in a practical respect. This determination, A 189 which for theoretical purposes would be transcendent, exceeding experience, is for practical purposes immanent. But we could take no such step with regard to the second dynamical idea, that of a necessary being. We could not ascend to it from the sensible world without the mediation of the first dynamical idea. For if we wished to try, we would have to risk the leap of leaving everything given to us behind and soaring toward something of which nothing is given to us that could mediate the connection of such an intelligible being with the sensible world, since the necessary being was to be cognized as given outside us. By contrast, as is now evident, this is quite possible with respect to our own subject: through the moral law it determines itself on the one hand as an intelligible being, by virtue of freedom, and on the other cognizes itself as active in the sensible world according to this determination. The concept of freedom alone allows us to find the unconditioned and intelligible for the conditioned and sensible without having to go outside ourselves. For it is our reason V:106 itself that, through the supreme and unconditioned practical law, cognizes itself and the being conscious of this law—our own person—as belonging to the pure world of understanding, and indeed even determines the manner A 190 in which it can be active as such a being. We can thus understand why, within the entire faculty of reason, only the practical can lead us beyond the sensible world and supply cognitions of a supersensible order and connection; but precisely for this reason, of course, these cognitions can be extended only as far as is strictly necessary for the pure practical purpose.

Allow me on this occasion to draw attention to just one more thing: every step taken with pure reason, even in the practical field, where subtle speculation is entirely disregarded, nevertheless accords so precisely and spontaneously with every element of the critique of theoretical reason that it is as though each step had been deliberately and carefully devised solely to confirm that critique. This exact agreement of the most important propositions of practical reason with the often seemingly oversubtle and unnecessary observations of the critique of speculative reason is in no way sought out, but arises of itself—as anyone can be convinced by simply pursuing moral investigations to their principles. It surprises us, fills us with wonder, and strengthens the maxim already recognized and praised by others: in every scientific investigation, continue undisturbed on your course with all possible precision and openness, without attending to A 191 what it might conflict with outside its field, but carry it through on its own as truthfully and completely as you can. Repeated observation has convinced me that, once this work is brought to completion, what halfway through sometimes seemed very doubtful to me in relation to other doctrines outside it finally agreed perfectly, in an unexpected way, with what had emerged of itself without the slightest regard for those doctrines, without partiality or preference for them—provided I set that doubt aside for the time being and attended solely to my work until it was complete. Writers would spare themselves many errors and much wasted effort, wasted because directed toward illusion, if only they could resolve to proceed with a little more openness.

Critical examination of the Analytic of Pure Practical Reason.

By a critical examination of a science, or of a part of it that forms a system in its own right, I mean this: investigating and justifying why it must have precisely this systematic form and no other, when compared with another system based on a similar cognitive faculty. Practical and speculative reason are based on the same cognitive faculty insofar as both are pure reason. We must therefore compare them to determine and explain the difference between their systematic forms.

The Analytic of Pure Theoretical Reason dealt with cognition of objects that may be given to the understanding. A 160 It therefore had to start with intuition, and so with sensibility, since intuition is always sensible. Only then could it move on to concepts of the objects of this intuition. Only after presenting both could it end with principles. Practical reason, by contrast, is not concerned with cognizing objects. It is concerned with its own capacity to make them real, in accordance with its cognition of them. In other words, it deals with a will: a causality whose determining ground lies in reason. So it does not have to supply an object of intuition. As practical reason, it needs to supply only a law of that causality. For the concept of causality always involves a relation to a law that determines how the various elements exist in relation to one another. A critical examination of its analytic, insofar as it is to be practical reason—which is the real problem—must therefore start with the possibility of practical V:90 principles a priori. From there alone could it proceed to concepts of the objects of practical reason: the absolutely good and evil. It had first to supply these concepts in accordance with those principles. For before those principles, no cognitive faculty can supply these objects as good and evil. Only then could the final chapter close this part: the chapter on the A 161 relation of pure practical reason to sensibility, and on its necessary influence on sensibility, an influence knowable a priori. That is the chapter on moral feeling. The Analytic of Pure Practical Reason thus divided the full range of conditions for its use in complete correspondence with theoretical reason, but in the reverse order. The Analytic of Theoretical Pure Reason was divided into transcendental aesthetic and transcendental logic. That of practical reason was divided, in reverse, into the logic and aesthetic of pure practical reason—if I may use these otherwise quite unsuitable names here simply for the analogy. Logic, in turn, was divided there into the analytic of concepts and the analytic of principles; here, into the analytic of principles and concepts. There the aesthetic had two parts, because sensible intuition has two forms. Here sensibility is not considered as a capacity for intuition at all, but only as feeling, which can be a subjective ground of desire. In this respect pure practical reason allows no further division.

It is also easy to see why we did not actually adopt this two-part division with its subdivisions. The example of the earlier work might well have tempted us to try it at first. For what we are considering here is pure reason A 162 in its practical use. It therefore starts from principles a priori, not from empirical determining grounds. The division of the Analytic of Pure Practical Reason must consequently resemble a syllogism. It proceeds from the universal in the major premise, the moral principle, through the subsumption of possible actions as good or evil under that principle in the minor premise, to the conclusion: the subjective determination of the will, an interest in the practically possible good and the maxim based on that interest. Anyone who has found the propositions presented in the Analytic V:91 convincing will enjoy these comparisons, for they rightly encourage the hope that we may one day understand the unity of the entire faculty of pure reason, theoretical as well as practical, and derive everything from a single principle. This is an unavoidable need of human reason. It finds full satisfaction only in a completely systematic unity of its cognitions.

If we also consider the content of the cognition we can have of and through pure practical reason, as its Analytic presents it, we find differences as striking as the analogy between it and theoretical reason. In the case of theoretical reason, the capacity A 163 for pure rational cognition a priori could be proved quite easily and clearly by examples from the sciences. The sciences test their principles in so many ways through methodical use that there is less reason than in ordinary cognition to fear a hidden admixture of empirical grounds of cognition. But to show that pure reason, by itself and without any empirical determining ground mixed in, is also practical, we had to turn to the most ordinary practical use of reason. We had to establish the supreme practical principle as one that every person's natural reason recognizes as the highest law of their will: a law entirely a priori, independent of all sensory data. Even before science could take it up and use it, we had to establish and justify its pure origin in the judgment of ordinary reason itself. It was, so to speak, a fact preceding all quibbling about its possibility and all conclusions that might be drawn from it. What we have just said also explains this circumstance very well. Pure practical reason must begin with principles. These must therefore be the initial data underlying all science; they cannot first A 164 originate in science. Moreover, moral principles could be justified as principles of pure reason quite securely just by appealing to ordinary human understanding. For anything empirical that might slip into our V:92 maxims as a determining ground of the will immediately reveals itself through the feeling of pleasure or pain necessarily attached to it insofar as it arouses desire. Pure practical reason, however, directly resists accepting this feeling as a condition of its principle. Reason, in giving practical laws, resists every intrusive inclination. This resistance makes the difference between the empirical and rational determining grounds clear, prominent, and unmistakable, through a distinctive kind of sensation. This sensation does not precede practical reason's legislation. Rather, that legislation alone produces it, and does so as a constraint. It is the feeling of respect. No one has this respect for inclinations, whatever their kind, but people do have it for the law. The difference becomes so clear that anyone, even someone with the most ordinary understanding, should immediately see in a given example that empirical grounds for willing can advise them to follow their attractions, A 165 but can never require them to obey anything except the law of pure practical reason alone.

The first and most important task of the Analytic of Pure Practical Reason is therefore to distinguish the doctrine of happiness from the doctrine of morals. Empirical principles form the entire basis of the first, but must not enter the second even in the slightest degree. In making this distinction, the Analytic must be as precise—even, if that is what it takes, as painstaking—as any geometer in their work. Here the philosopher faces greater difficulty, as always in rational cognition through mere concepts without constructing them. No intuition can underlie a pure noumenon. But the philosopher also has an advantage. Almost like a chemist, the philosopher can at any time experiment with anyone's practical reason to distinguish the moral, pure determining ground from the empirical one. The experiment consists in adding the moral law as a determining ground to a will affected by experience—for example, the will of someone who would like to lie because it would gain them something. It is like a chemist adding alkali to a solution of lime in hydrochloric acid. The acid immediately leaves the lime and combines with the alkali, while the lime falls to the bottom. Likewise, A 166 present the moral V:93 law to someone who is otherwise honest, or who at least imagines being an honest person for the moment. Through that law they recognize a liar's worthlessness. Their practical reason immediately abandons the advantage, in judging what they ought to do, and joins with what preserves their respect for their own person: truthfulness. Once the advantage has been separated and washed clean of everything attached to it by reason—which stands entirely on the side of duty—anyone can then weigh it. It may still be combined with reason in other cases, but not where it could conflict with the moral law. Reason never abandons that law, but joins itself to it in the closest possible way.

But this distinction between the principle of happiness and the principle of morality does not by itself set them against each other. Pure practical reason does not ask us to give up our claims to happiness. It asks only that, whenever duty is at issue, we take no account of them. In a certain respect, caring for our happiness may even be a duty. This is partly because happiness—including skill, health, and wealth—provides means for fulfilling our duty, and partly because a lack of happiness, such as poverty, creates temptations A 167 to violate our duty. But promoting our happiness can never directly be a duty, much less the principle of all duty. Now every determining ground of the will except the one pure law of practical reason, the moral law, is empirical. As such, all these grounds belong to the principle of happiness. They must therefore all be separated from the supreme moral principle and never incorporated into it as a condition. That would destroy all moral worth, just as adding anything empirical to geometrical principles would destroy all mathematical certainty. This certainty is the finest thing mathematics possesses, in Plato's judgment, and it takes precedence even over all its usefulness.

Instead of a deduction of the supreme principle of pure practical reason—that is, an explanation of how such cognition a priori is possible—we could supply only the following point. If we understood how an efficient cause could be free, we would also understand not just the possibility but the necessity of the moral law as the supreme practical law of rational beings whose will is granted a free causality. For the two concepts are so inseparable that practical V:94 freedom could also be defined as the will's independence of every law other than A 168 the moral law alone. But we cannot possibly understand how an efficient cause can be free, especially in the world of sense. We are fortunate if we can be sufficiently assured that no proof of its impossibility can be given, and are then required by the moral law, which postulates freedom, to assume it, and by that very requirement also entitled to do so. Yet many people still believe they can explain freedom by empirical principles, like any other natural capacity. They treat it as a psychological property, whose explanation requires only a closer investigation of the nature of the soul and the will's incentives. They do not treat it as a transcendental predicate of the causality of a being belonging to the world of sense, though this alone is what really matters here. In this way they undo the wonderful disclosure that pure practical reason gives us through the moral law: the disclosure of an intelligible world by giving reality to the otherwise transcendent concept of freedom. They thereby undo the moral law itself, which admits no empirical determining ground at all. So we must add something here to guard against this illusion and expose the full shallowness of empiricism.

The concept of causality as natural necessity, as distinct A 169 from causality as freedom, concerns the existence of things only insofar as it can be determined in time. It therefore concerns them as appearances, in contrast to their causality as things in themselves. If we take the determinations of things' existence in time to be determinations of things in themselves—as people most commonly do—necessity in causal relations cannot be reconciled with freedom in any way. They contradict each other. For natural necessity implies that every event, and therefore every action occurring at a particular time, is necessary under the conditions of what existed at an earlier time. But past time is no longer within my control. Every action I perform must therefore be made necessary by determining grounds that are not within my control. In other words, at the moment I act I am never free. Even if I assumed that my entire existence was independent of any external cause, such as God, V:95 so that the determining grounds of my causality and even of my entire existence lay nowhere outside me, this would not turn that natural necessity into freedom in the least. For at every moment I would still necessarily be determined to act by what is not within my control. A 170 The series of events, stretching infinitely backward, would be an unbroken chain of nature. I would only ever continue it according to an already determined order, never start it on my own at any point. My causality would therefore never be freedom.

If we want to ascribe freedom to a being whose existence is determined in time, we cannot, at least in this respect, exempt it from the law of natural necessity governing all events in its existence, and so its actions too. That would amount to handing it over to blind chance. But this law inevitably concerns all the causality of things insofar as their existence in time can be determined. If this were also how we had to represent the existence of these things in themselves, freedom would have to be rejected as an empty and impossible concept. So if we still want to save freedom, only one course remains. We must ascribe a thing's existence, insofar as it is determinable in time, and thus its causality under the law of natural necessity, only to appearance. We must ascribe freedom to the very same being as a thing in itself. This is certainly unavoidable if we want to preserve both conflicting concepts. Yet when we apply them and try to explain how they are united A 171 in one and the same action, great difficulties arise. These seem to make such a union impossible.

Suppose I say of someone who commits a theft that, under the natural law of causality, this deed necessarily resulted from determining grounds in the preceding time. Then it was impossible for the deed not to occur. How can judging it by the moral law change anything here? How can that judgment assume that the deed could have been left undone because the law says it ought to have been left undone? In other words, how can the person be called entirely free at the very time, and with respect to the very action, in which they are also subject to unavoidable V:96 natural necessity? One attempted escape merely adjusts the kind of grounds determining their causality under natural law to a comparative concept of freedom. On this concept, an effect is sometimes called free when its determining natural ground lies inside the acting being. Thus we speak of a thrown body's free motion because, while it is flying, nothing outside it drives it. Or we call a clock's movement free because it drives its hand itself, without the hand needing to be pushed A 172 from outside. In the same way, people call human actions free despite their being made necessary by determining grounds preceding them in time. They do so because these actions arise from internal representations produced by our own powers, from desires generated through those representations in response to circumstances, and thus from our own choice. This is a miserable expedient. Some people still let it put them off and think they have solved, with a little quibbling over words, the difficult problem that millennia have worked on in vain. Its solution is hardly likely to lie so plainly on the surface. For the freedom that must underlie all moral laws and all imputation in accordance with them is not at all a question of whether causality determined by a natural law is made necessary by determining grounds inside the subject or outside it. Nor, in the first case, does it matter whether these grounds are instinctive or thought out by reason. These very people admit that the determining representations have the ground of their existence in time, specifically in the previous state, which in turn has its ground in an earlier state, and so on. However internal these determinations may be, and even if their causality is psychological rather than mechanical A 173—producing action through representations rather than bodily movement—they remain determining grounds of the causality of a being insofar as its existence is determinable in time. They therefore fall under necessitating conditions of past time. When the subject is to act, these are no longer within its control. They may involve psychological freedom, if one insists on using this word for a merely internal chain of the soul's representations. But they still involve natural necessity and thus leave no transcendental V:97 freedom. That freedom must be thought as independence from everything empirical, and thus from nature altogether—whether nature is considered as an object of inner sense only in time, or also of outer sense in both space and time. Without freedom in this latter, proper sense, which alone is practical a priori, no moral law and no imputation according to it are possible. For this very reason, all the necessity of events in time under the natural law of causality can also be called the mechanism of nature. This does not mean that the things subject to it must be actual material machines. We are concerned only with the necessary connection of events in a temporal series as it unfolds under natural law. We may call the subject in which this A 174 process occurs a material automaton, if matter drives the machinery, or, with Leibniz, a spiritual automaton, if representations drive it. If our will had no freedom beyond the latter—psychological and comparative freedom, rather than also transcendental, that is, absolute freedom—then fundamentally it would be no better than the freedom of a roasting spit. Once wound up, that too carries out its movements by itself.

To remove the apparent contradiction between natural mechanism and freedom in the same action in the case presented, we must recall what was said in the Critique of Pure Reason, or follows from it. The natural necessity that cannot coexist with the subject's freedom attaches only to determinations of a thing subject to conditions of time. It therefore attaches only to those of the acting subject as an appearance. In this respect, the determining grounds of each of its actions lie in what belongs to past time and is no longer within its control. These grounds must include its already committed deeds and the character determinable through them in its own eyes as a phenomenon. But the very same subject A 175 is also conscious of itself as a thing in itself. In this other respect, it considers its existence insofar as that existence is not subject to conditions of time, and considers itself determinable only by laws it gives itself through reason. In this existence, nothing precedes its determination of the will. Rather, every action and, in general, V:98 every changing determination of its existence according to inner sense—even the whole sequence of its existence as a sensible being—must, in the consciousness of its intelligible existence, be regarded only as a consequence. It must never be regarded as a determining ground of its causality as a noumenon. In this respect, a rational being can rightly say of every unlawful action it commits that it could have left that action undone, even though the action as an appearance is sufficiently determined by the past and is therefore unavoidably necessary. For that action, together with all the past that determines it, belongs to a single manifestation of its character, a character it has made for itself. In accordance with that character, it imputes to itself, as a cause independent of all sensibility, the causality of those appearances.

The judgments of that remarkable capacity within us called conscience agree completely with this. A person may use every clever device to picture unlawful conduct A 176 they remember as an unintentional mistake, a mere carelessness that can never be entirely avoided. They may present it as something in which the current of natural necessity swept them along, and so declare themselves innocent. Yet they find that the advocate speaking in their favor cannot silence the accuser within them, if they are conscious that, when they committed the wrong, they were in their senses—that is, using their freedom. They may indeed explain their offense by a bad habit acquired through gradually neglecting to watch themselves, until they can view it as that habit's natural consequence. But this still cannot protect them from self-reproach and their own rebuke. This also explains remorse over a deed committed long ago whenever it is recalled. Remorse is a painful sensation produced by a moral disposition. It is practically empty insofar as it cannot undo what has been done. It would even be absurd—as Priestley, a genuine and consistent fatalist, declares it to be. For this frankness he deserves more approval than those who assert the will's mechanism in fact but its freedom in A 177 words. Without making the possibility of such imputation understandable, V:99 they still want to be thought to include freedom in their syncretistic system. Yet as pain, remorse is entirely legitimate. For when the moral law, the law of our intelligible existence, is at issue, reason recognizes no difference of time. It asks only whether the event belongs to me as my deed. If it does, reason always connects the same sensation with it morally, whether it is happening now or happened long ago. For in relation to the intelligible consciousness of one's existence, freedom, one's sensible life has the absolute unity of a single phenomenon. Insofar as it contains only appearances of one's disposition concerning the moral law—one's character—it must be judged not by the natural necessity that belongs to it as an appearance, but by the absolute spontaneity of freedom. We can therefore concede the following. If we could see so deeply into a person's way of thinking, as shown in both inner and outer actions, that we knew every incentive, even the slightest, and all the external occasions affecting those incentives, we could calculate that person's future behavior as certainly as a lunar or solar eclipse. Yet we could still maintain that the person A 178 is free. For suppose we were also capable of another kind of vision, an intellectual intuition of the same subject. We certainly have no such vision; we have only the rational concept in its place. But if we had it, we would see that, regarding anything that can concern the moral law, this whole chain of appearances depends on the spontaneity of the subject as a thing in itself. No physical explanation can be given of what determines that spontaneity. In the absence of this intuition, the moral law assures us of a distinction between two relations. One relates our actions as appearances to our subject's sensible being. The other relates this sensible being itself to the intelligible basis within us.—This perspective is natural to our reason, though inexplicable. It also lets us justify judgments that, despite being made with complete conscientiousness, initially seem to conflict with all fairness. There are cases in which people display wickedness from childhood, even under an upbringing that proved beneficial to others raised alongside them. Their wickedness starts so early and continues increasing into adulthood that they are considered born villains and completely beyond reform V:100 in their way of thinking. Yet we judge their acts and omissions just as we judge anyone else's, A 179 and reproach them for their crimes as their own fault. Even these children themselves find the reproaches entirely justified, as though they remained as responsible as anyone else despite the hopeless natural condition of mind attributed to them. This would be impossible unless we assumed that everything arising from a person's choice—as every deliberately committed action undoubtedly does—rests on a free causality. From early youth, that causality expresses its character in its appearances, its actions. The uniformity of the person's behavior reveals a natural connection among them. But that connection does not make the will's bad character necessary. Rather, it results from evil and unchanging principles freely adopted. These only make the person still more blameworthy and deserving of punishment.

But another difficulty still faces freedom insofar as it is to be united with natural mechanism in a being belonging to the world of sense. Even after everything said so far has been conceded, this difficulty still threatens freedom with complete destruction. Yet one circumstance in this danger also offers hope of an outcome favorable to freedom. The same difficulty weighs much more heavily—in A 180 fact, as we shall soon see, exclusively—on the system that treats existence determinable in time and space as the existence of things in themselves. It therefore does not force us to abandon our main assumption: the ideality of time as a mere form of sensible intuition, and thus as merely a way of representing things peculiar to the subject as a member of the world of sense. We need only reconcile the difficulty with this idea.

Suppose we are granted that the intelligible subject can still be free regarding a given action, although as a subject also belonging to the world of sense it is mechanically conditioned regarding that same action. Still, as soon as we assume that God, as the universal original being, is also the cause of the existence of substance, a problem seems to follow. We must never abandon that proposition without also abandoning the concept of God as the being of all beings and so his complete sufficiency, on which everything in theology depends. But it seems that we must then also concede that human actions have their V:101 determining ground in what is entirely outside the person's control: the causality of a supreme being distinct from them, on whom their existence and the entire determination of their causality wholly depend. Indeed, if A 181 human actions, as determinations of a person in time, were not mere determinations of the person as an appearance but as a thing in itself, freedom could not be saved. A human being would be a marionette or a Vaucanson automaton, built and wound up by the supreme maker of all works of art. Self-consciousness would indeed make it a thinking automaton. But its consciousness of its own spontaneity would be sheer illusion if taken for freedom. That spontaneity deserves the name only comparatively. The nearest determining causes of its motion, and a long series extending upward toward their determining causes, would indeed be internal. But the final and highest cause would still lie entirely in another's hand. So I do not see how those who still insist on treating time and space as determinations belonging to the existence of things in themselves intend to avoid fatalism about actions here. Or suppose they simply grant—as the otherwise acute Mendelssohn did—that both are necessary conditions only of the existence of finite and derivative beings, not of the infinite original being. How can they justify their authority to make such a distinction? How can they even avoid the contradiction A 182 they commit? They treat existence in time as a determination necessarily attached to finite things in themselves. Yet God is the cause of this existence, although he cannot be the cause of time or space itself, since these must be presupposed a priori as necessary conditions of things' existence. His causality with respect to the existence of these things must therefore itself be conditioned by time. All the contradictions with the concepts of his infinity and independence must then inevitably arise. By contrast, we can very easily distinguish the determination of divine existence as independent of all conditions of time from that of a being in the world of sense. It is the distinction between the existence of a being in itself and that of a thing in appearance. Hence, unless we accept the ideality of time and space, V:102 only Spinozism remains. In it, space and time are essential determinations of the original being itself. Things dependent on it—including ourselves—are not substances, but merely accidents inherent in it. For if these things exist merely as its effects in time, which would be the condition of their existence in themselves, then the actions of these beings must also be merely its actions, performed somewhere and sometime. Thus, despite the absurdity of its basic idea, A 183 Spinozism reasons far more consistently than a theory of creation can if the latter assumes substances that are beings existing in themselves in time, treats them as effects of a supreme cause, yet regards them not as belonging to that cause and its action but as substances in their own right.

The difficulty just mentioned can be resolved briefly and clearly as follows. Suppose existence in time is merely a sensible way in which thinking beings in the world represent things, and therefore does not concern them as things in themselves. Then the creation of these beings is a creation of things in themselves. For the concept of creation does not belong to the sensible way of representing existence and causality; it can refer only to noumena. Thus, when I say of beings in the world of sense that they are created, I am considering them in this respect as noumena. It would be a contradiction to say that God is a creator of appearances. Likewise, it is a contradiction to say that, as creator, he is the cause of actions in the world of sense, and thus of actions as appearances, even though he is the cause of the existence of the acting beings as noumena. Now suppose we can affirm freedom without impairing the natural mechanism A 184 of actions as appearances, by taking existence in time to apply only to appearances, not to things in themselves. Then the fact that the acting beings are creatures cannot change this in the least. For creation concerns their intelligible, not their sensible, existence. It therefore cannot be regarded as a determining ground of appearances. The outcome would be entirely different, however, if beings in the world existed in time as things in themselves. In that case the creator of the substance would also be the author of the whole mechanism in that substance.

That is how important it is to separate time, as well as space, from the existence of things in themselves, as was done in the Critique of Pure Speculative V:103 Reason.

Someone may object that the solution to the difficulty presented here still contains much that is hard and scarcely allows a clear presentation. But is any other solution that has been or might be tried easier and more understandable? We might sooner say that the dogmatic teachers of metaphysics have shown more cunning than honesty by keeping this difficult point out of sight as much as possible. They hope that, if they say nothing about it, scarcely anyone will think of it either. If a science is to be helped, all its difficulties must be exposed. Even those that stand in its way A 185 most secretly must be sought out. For each calls for a remedy that cannot be found without adding to the science, either in scope or in precision. Thus even obstacles become means of making the science more thorough. But if difficulties are deliberately concealed or removed only by temporary remedies, sooner or later they develop into incurable evils that destroy the science through complete skepticism.

Among all the ideas of pure speculative reason, it is really the concept of freedom alone that provides so great an extension into the supersensible, even if only for practical cognition. So I ask myself: why has this concept alone proved so fruitful, while the others merely mark an empty place for possible pure beings of the understanding, without being able to determine their concept in any way? I soon see that, since I cannot think anything without a category, I must first look for the category in reason's idea of freedom, which is what concerns me here. This is the category of causality. No corresponding intuition can be supplied A 186 for the rational concept of freedom, since it goes beyond experience. Yet a sensible intuition must first be given for the concept of the understanding, causality, for whose synthesis that rational concept demands the unconditioned. This first secures causality's objective reality. V:104 Now all categories are divided into two classes: the mathematical, which concern only the unity of synthesis in representing objects, and the dynamical, which concern that unity in representing the existence of objects. The first class, quantity and quality, always involves a synthesis of homogeneous elements. In such a synthesis, the unconditioned for what is given as conditioned in sensible intuition in space and time cannot be found at all. For it too would have to belong to space and time, and so would always be conditioned in turn. That is why, in the Dialectic of Pure Theoretical Reason, both opposed ways of finding the unconditioned and the totality of conditions for these categories were false. The categories of the second class, causality and the necessity of a thing, did not require this homogeneity between the conditioned and its condition in the synthesis. Here we were not to represent how intuition is composed from the manifold within it. We were to represent only how the existence of the conditioned object corresponding to it is added to the existence of the condition, A 187 as connected with it in the understanding. Here we were allowed to locate the unconditioned, though otherwise undetermined, in the intelligible world for what is thoroughly conditioned in the world of sense—both regarding causality and regarding the contingent existence of things themselves—and to make the synthesis transcendent. Hence the Dialectic of Pure Speculative Reason found that the two apparently opposed ways of finding the unconditioned for the conditioned did not actually contradict each other. For example, in the synthesis of causality, one could think a causality not itself sensibly conditioned for what is conditioned in the series of causes and effects in the world of sense. The same action that, as belonging to the world of sense, is always sensibly conditioned and thus mechanically necessary could also have a sensibly unconditioned causality as its basis, insofar as it belongs to the causality of the acting being as a member of the intelligible world. Thus it could be thought as free. What remained was simply to turn this possibility into actuality. In other words, in an actual case we had to prove, as though by a fact, that certain actions presuppose such a causality—an intellectual causality unconditioned by sense—whether these actions are actual or merely commanded, that is, objectively necessary in practice. We could not hope to find this connection in actions actually given in experience as events in the world of sense. A 188 V:105 For causality through freedom must always be sought outside the world of sense, in the intelligible. But no things other than sensible beings are given to us for perception and observation. Only one possibility therefore remained: to find an indisputable and objective principle of causality that excludes every sensible condition from its determination. In such a principle, reason would not appeal to anything else as a determining ground of causality. Rather, through that principle it would already contain that ground itself, and would thus itself be practical as pure reason. This principle needs neither searching for nor inventing. It has long existed in everyone's reason and is incorporated into reason's nature: it is the principle of morality. Thus that unconditioned causality and the capacity for it, freedom, are not merely thought in an undetermined and problematic way. Nor is the being possessing them—myself, belonging to the world of sense yet also to the intelligible world—merely thought in that way, which speculative reason could already establish as possible. Rather, they are determined with regard to the law of their causality and cognized as actual. In this way the reality of the intelligible world has been given to us, and determined in a practical respect. This determination, A 189 which would be transcendent, going beyond bounds, for theoretical purposes, is immanent, staying within bounds, for practical purposes. But we could not take such a step regarding the second dynamical idea, that of a necessary being. We could not rise to it from the world of sense without the mediation of the first dynamical idea. For to try would have meant daring to leap away from everything given to us toward something of which nothing is given that could connect such an intelligible being with the world of sense. For the necessary being was to be cognized as given outside us. By contrast, as what we have just shown makes clear, such a connection is entirely possible concerning our own subject. Through the moral law, it determines itself on one side as an intelligible being, through freedom, and on the other side cognizes itself as acting in the world of sense in accordance with this determination. The concept of freedom alone lets us find the unconditioned and intelligible for the conditioned and sensible without going outside ourselves. For it is our reason V:106 itself that, through the highest and unconditioned practical law, cognizes itself and the being conscious of this law—our own person—as belonging to the pure world of the understanding. It even determines the way A 190 in which that being can act as such. This makes it understandable why, in the whole faculty of reason, only the practical can take us beyond the world of sense and supply cognitions of a supersensible order and connection. But for that very reason, these cognitions can extend only as far as pure practical purposes strictly require.

Let me draw attention to just one more point on this occasion. Every step taken with pure reason, even in the practical field where subtle speculation is disregarded entirely, nevertheless fits every aspect of the critique of theoretical reason so exactly, and so spontaneously, that each step seems carefully planned solely to confirm that critique. This exact agreement between the most important propositions of practical reason and the remarks in the critique of speculative reason, which often seem too subtle and unnecessary, is surprising and astonishing. It is not sought in any way; it emerges by itself. Anyone can verify this simply by pursuing moral investigations back to their principles. It reinforces a maxim others have already recognized and praised: in every scientific investigation, proceed steadily with all possible precision and openness. Do not worry A 191 about what it might conflict with outside its own field. Instead, carry it out on its own as truthfully and completely as possible. Repeated observation has convinced me of this. Halfway through such work, something sometimes seemed very doubtful to me in view of other doctrines outside it. But if I put that concern out of sight for the time being and attended only to my work until it was finished, the result finally agreed perfectly, in an unexpected way, with what had emerged on its own, without the slightest regard for those doctrines and without bias or preference for them. Writers would spare themselves many errors and much wasted effort—effort based on illusion—if only they could resolve to work with somewhat more openness.