I.2.2. The Final Purpose of the Natural Dialectic of Human Reason

The ideas of pure reason can never be dialectical in themselves; any deceptive illusion to which they give occasion must be due solely to their misemployment. For they arise from the very nature of our reason; and it is impossible that this highest tribunal of all the rights and claims of speculation should itself be the source of deceptions and illusions. Presumably, therefore, the ideas have their own good and appropriate vocation as determined by the natural disposition of our reason. The mob of sophists, however, raise against reason the usual cry of absurdities and contradictions, and though unable to penetrate to its innermost designs, they none the less inveigh against its prescriptions. Yet it is to the beneficent influences exercised by reason that they owe the possibility of their own self-assertiveness, and indeed that very culture which enables them to blame and to condemn what reason requires of them.

We cannot employ an a priori concept with any certainty without having first given a transcendental deduction of it. The ideas of pure reason do not, indeed, admit of the kind of deduction that is possible in the case of the categories. But if they are to have the least objective validity, no matter how indeterminate that validity may be, and are not to be mere empty thought-entities (entia rationis ratiocinantis),a a deduction of them must be possible, however greatly (as we admit) it may differ from that which we have been able to give of the categories. This will complete the critical work of pure reason, and is what we now propose to undertake.

There is a great difference between something being given to my reason as an object absolutely, or merely as an object in the idea. In the former case our concepts are employed to determine the object; in the latter case there is in fact only a schema for which no object, not even a hypothetical one, is directly given, and which only enables us to represent to ourselves other objects in an indirect manner, namely in their systematic unity, by means of their relation to this idea. Thus I say that the concept of a highest intelligence is a mere idea, that is to say, its objective reality is not to be taken as consisting in its referring directly to an object (for in that sense we should not be able to justify its objective validity). It is only a schema constructed in accordance with the conditions of the greatest possible unity of reason—the schema of the concept of a thing in general, which serves only to secure the greatest possible systematic unity in the empirical employment of our reason. We then, as it were, derive the object of experience from the supposed object of this idea, viewed as the ground or cause of the object of experience. We declare, for instance, that the things of the world must be viewed as they received their existence from a highest intelligence. The idea is thus really only a heuristic, not an ostensive concept. It does not show us how an object is constituted, but how, under its guidance, we should seek to determine the constitution and connection of the objects of experience. If, then, it can be shown that the three transcendental ideas (the psychological, the cosmological, and the theological), although they do not directly relate to, or determine, any object corresponding to them, none the less, as rules of the empirical employment of reason, lead us to systematic unity, under the presupposition of such an object in the idea; and that they thus contribute to the extension of empirical knowledge, without ever being in a position to run counter to it, we may conclude that it is a necessary maxim of reason to proceed always in accordance with such ideas. This, indeed, is the transcendental deduction of all ideas of speculative reason, not as constitutive principles for the extension of our knowledge to more objects than experience can give, but as regulative principles of the systematic unity of the manifold of empirical knowledge in general, whereby this empirical knowledge is more adequately secured within its own limits and more effectively improved than would be possible, in the absence of such ideas, through the employment merely of the principles of the understanding.

I shall endeavour to make this clearer. In conformity with these ideas as principles we shall, first, in psychology, under the guidance of inner experience, connect all the appearances, all the actions and receptivity of our mind, as the mind were a simple substance which persists with personal identity (in this life at least), while its states, to which those of the body belong only as outer conditions, are in continual change. Secondly, in cosmology, we must follow up the conditions of both inner and outer natural appearances, in an enquiry which is to be regarded as never allowing of completion, just as if the series of appearances were in itself endless, without any first or supreme member. We need not, in so doing, deny that, outside all appearances, there are purely intelligible grounds of the appearances; but as we have no knowledge of these whatsoever, we must never attempt to make use of them in our explanations of nature. Thirdly, and finally, in the domain of theology, we must view everything that can belong to the context of possible experience as if this experience formed an absolute but at the same time completely dependent and sensibly conditioned unity, and yet also at the same time as if the sum of all appearances (the sensible world itself) had a single, highest and all-sufficient ground beyond itself, namely, a self-subsistent, original, creative reason. For it is in the light of this idea of a creative reason that we so guide the empirical employment of our reason as to secure its greatest possible extension—that is, by viewing all objects as if they drew their origin from such an archetype. In other words, we ought not to derive the inner appearances of the soul from a simple thinking substance but from one another, in accordance with the idea of a simple being; we ought not to derive the order and systematic unity of the world from a supreme intelligence, but to obtain from the idea of a supremely wise cause the rule according to which reason in connecting empirical causes and effects in the world may be employed to best advantage, and in such manner as to secure satisfaction of its own demands.

Now there is nothing whatsoever to hinder us from assuming these ideas to be also objective, that is, from hypostatising them—except in the case of the cosmological ideas, where reason, in so proceeding, falls into antinomy. The psychological and theological ideas contain no antinomy, and involve no contradiction. How, then, can anyone dispute their [possible] objective reality? He who denies their possibility must do so with just as little knowledge [of this possibility] as we can have in affirming it. It is not, however, a sufficient ground for assuming anything, that there is no positive hindrance to our so doing; we are not justified in introducing thought-entities which transcend all our concepts, though without contradicting them, as being real and determinate objects, merely on the authority of a speculative reason that is bent upon completing the tasks which it has set itself. They ought not to be assumed as existing in themselves, but only as having the reality of a schema—the schema of the regulative principle of the systematic unity of all knowledge of nature. They should be regarded only as analoga of real things, not as in themselves real things. We remove from the object of the idea the conditions which limit the concept provided by our understanding, but which also alone make it possible for us to have a determinate concept of anything. What we then think is a something of which, as it is in itself, we have no concept whatsoever, but which we none the less represent to ourselves as standing to the sum of appearances in a relation analogous to that in which appearances stand to one another.

If, in this manner, we assume such ideal beings, we do not really extend our knowledge beyond the objects of possible experience; we extend only the empirical unity of such experience, by means of the systematic unity for which the schema is provided by the idea—an idea which has therefore no claim to be a constitutive, but only a regulative principle. For to allow that we posit a thing, a something, a real being, corresponding to the idea, is not to say that we profess to extend our knowledge of things by means of transcendental concepts. For this being is posited only in the idea and not in itself; and therefore only as expressing the systematic unity which is to serve as a rule for the empirical employment of reason. It decides nothing in regard to the ground of this unity or as to what may be the inner character of the being on which as cause the unity depends.

Thus the transcendental, and the only determinate, concept which the purely speculative reason gives us of God is, in the strictest sense, deistic; that is, reason does not determine the objective validity of such a concept, but yields only the idea of something which is the ground of the highest and necessary unity of all empirical reality. This something we cannot think otherwise than on the analogy of a real substance that, in conformity with laws of reason, is the cause of all things. This, indeed, is how we must think it, in so far as we venture to think it as a special object, and do not rather remain satisfied with the mere idea of the regulative principle of reason, leaving aside the completion of all conditions of thought as being too surpassingly great for the human understanding. The latter procedure is, however, inconsistent with the pursuit of that complete systematic unity in our knowledge to which reason at least sets no limits.

This, then, is how matters stand: if we assume a divine being, we have indeed no concept whatsoever either of the inner possibility of its supreme perfection or of the necessity of its existence; but, on the other hand, we are in a position to give a satisfactory answer to all those questions which relate to the contingent, and to afford reason the most complete satisfaction in respect to that highest unity after which it is seeking in its empirical employment. The fact, however, that we are unable to satisfy reason in respect to the assumption itself, shows that it is the speculative interest of reason, not any insight, which justifies it in thus starting from a point that lies so far above its sphere; and in endeavouring, by this device, to survey its objects as constituting a complete whole.

We here come upon a distinction bearing on the procedure of thought in dealing with one and the same assumption, a distinction which is somewhat subtle, but of great importance in transcendental philosophy. I may have sufficient ground to assume something, in a relative sense (suppositio relativa), and yet have no right to assume it absolutely (suppositio absoluta). This distinction has to be reckoned with in the case of a merely regulative principle. We recognise the necessity of the principle, but have no knowledge of the source of its necessity; and in assuming that it has a supreme ground, we do so solely in order to think its universality more determinately. Thus, for instance, when I think as existing a being that corresponds to a mere idea, indeed to a transcendental idea, I have no right to assume any such thing as in itself existing, since no concepts through which I am able to think any object as determined suffice for such a purpose—the conditions which are required for the objective validity of my concepts being excluded by the idea itself. The concepts of reality, substance, causality, even that of necessity in existence, apart from their use in making possible the empirical knowledge of an object, have no meaning whatsoever, such as might serve to determine any object. They can be employed, therefore, to explain the possibility of things in the world of sense, but not to explain the possibility of the universe itself. Such a ground of explanation would have to be outside the world, and could not therefore be an object of a possible experience. None the less, though I cannot assume such an inconceivable being [as existing] in itself, I may yet assume it as the object of a mere idea, relatively to the world of sense. For if the greatest possible empirical employment of my reason rests upon an idea (that of systematically complete unity, which I shall presently be defining more precisely), an idea which, although it can never itself be adequately exhibited in experience, is yet indispensably necessary in order that we may approximate to the highest possible degree of empirical unity, I shall not only be entitled, but shall also be constrained, to realise this idea, that is, to posit for it a real object. But I may posit it only as a something which I do not at all know in itself, and to which, as a ground of that systematic unity, I ascribe, in relation to this unity, such properties as are analogous to the concepts employed by the understanding in the empirical sphere. Accordingly, in analogy with realities in the world, that is, with substances, with causality and with necessity, I think a being which possesses all this in the highest perfection; and since this idea depends merely on my reason, I can think this being as self-subsistent reason, which through ideas of the greatest harmony and unity is the cause of the universe. I thus omit all conditions which might limit the idea, solely in order, under countenance of such an original ground, to make possible systematic unity of the manifold in the universe, and thereby the greatest possible empirical employment of reason. This I do by representing all connections as if they were the ordinances of a supreme reason, of which our reason is but a faint copy. I then proceed to think this supreme being exclusively through concepts which, properly, are applicable only in the world of sense. But since I make none but a relative use of the transcendental assumption, namely, as giving the substratum of the greatest possible unity of experience, I am quite in order in thinking a being which I distinguish from the world of sense, through properties which belong solely to that world. For I do not seek, nor am I justified in seeking, to know this object of my idea according to what it may be in itself. There are no concepts available for any such purpose; even the concepts of reality, substance, causality, nay, even that of necessity in existence, lose all meaning, and are empty titles for [possible] concepts, themselves entirely without content, when we thus venture with them outside the field of the senses. I think to myself merely the relation of a being, in itself completely unknown to me, to the greatest possible systematic unity of the universe, solely for the purpose of using it as a schema of the regulative principle of the greatest possible empirical employment of my reason.

If it be the transcendental object of our idea that we have in view, it is obvious that we cannot thus, in terms of the concepts of reality, substance, causality, etc., presuppose its reality in itself, since these concepts have not the least application to anything that is entirely distinct from the world of sense. The supposition which reason makes of a supreme being, as the highest cause, is, therefore relative only; it is devised solely for the sake of systematic unity in the world of sense, and is a mere something in idea, of which, as it may be in itself, we have no concept This explains why, in relation to what is given to the senses as existing, we require the idea of a primordial being necessary in itself, and yet can never form the slightest concept of it or of its absolute necessity.

We are now in a position to have a clear view of the outcome of the whole Transcendental Dialectic, and accurately to define the final purpose of the ideas of pure reason, which become dialectical only through heedlessness and misapprehension. Pure reason is in fact occupied with nothing but itself. It can have no other vocation. For what is given to it does not consist in objects that have to be brought to the unity of the empirical concept, but in those modes of knowledge supplied by the understanding that require to be brought to the unity of the concept of reason—that is, to unity of connection in conformity with a principle. The unity of reason is the unity of system; and this systematic unity does not serve objectively as a principle that extends the application of reason to objects, but subjectively as a maxim that extends its application to all possible empirical knowledge of objects. Nevertheless, since the systematic connection which reason can give to the empirical employment of the understanding not only furthers its extension, but also guarantees its correctness, the principle of such systematic unity is so far also objective, but in an indeterminate manner (principium vagum). It is not a constitutive principle that enables us to determine anything in respect of its direct object, but only a merely regulative principle and maxim, to further and strengthen in infinitum (indeterminately) the empirical employment of reason—never in any way proceeding counter to the laws of its empirical employment, and yet at the same time opening out new paths which are not within the cognisance of the understanding.

But reason cannot think this systematic unity otherwise than by giving to the idea of this unity an object; and since experience can never give an example of complete systematic unity, the object which we have to assign to the idea is not such as experience can ever supply. This object, as thus entertained by reason (ens rationis ratiocinatae), is a mere idea; it is not assumed as a something that is real absolutely and in itself, but is postulated only problematically (since we cannot reach it through any of the concepts of the understanding) in order that we may view all connection of the things of the world of sense as if they had their ground in such a being. In thus proceeding, our sole purpose is to secure that systematic unity which is indispensable to reason, and which while furthering in every way the empirical knowledge obtainable by the understanding can never interfere to hinder or obstruct it.

We misapprehend the meaning of this idea if we regard it as the assertion or even as the assumption of a real thing, to which we may proceed to ascribe the ground of the systematic order of the world. On the contrary, what this ground which eludes our concepts may be in its own inherent constitution is left entirely undetermined; the idea is posited only as being the point of view from which alone that unity, which is so essential to reason and so beneficial to the understanding, can be further extended. In short, this transcendental thing is only the schema of the regulative principle by which reason, so far as lies in its power, extends systematic unity over the whole field of experience.

The first object of such an idea is the ‘I’ itself, viewed simply as thinking nature or soul. If I am to investigate the properties with which a thinking being is in itself endowed, I must interrogate experience. For I cannot even apply any one of the categories to this object, except in so far as the schema of the category is given in sensible intuition. But I never thereby attain to a systematic unity of all appearances of inner sense. Instead, then, of the empirical concept (of that which the soul actually is), which cannot carry us far, reason takes the concept of the empirical unity of all thought; and by thinking this unity as unconditioned and original, it forms from it a concept of reason, that is, the idea of a simple substance, which, unchangeable in itself (personally identical), stands in association with other real things outside it; in a word, the idea of a simple self-subsisting intelligence. Yet in so doing it has nothing in view save principles of systematic unity in the explanation of the appearances of the soul. It is endeavouring to represent all determinations as existing in a single subject, all powers, so far as possible, as derived from a single fundamental power, all change as belonging to the states of one and the same permanent being, and all appearances in space as completely different from the actions of thought. The simplicity and other properties of substance are intended to be only the schema of this regulative principle, and are not presupposed as being the actual ground of the properties of the soul. For these may rest on altogether different grounds, of which we can know nothing. The soul in itself could not be known through these assumed predicates, not even if we regarded them as absolutely valid in respect of it. For they constitute a mere idea which cannot be represented in concreto. Nothing but advantage can result from the psychological idea thus conceived, if only we take heed that it is not viewed as more than a mere idea, and that it is therefore taken as valid only relatively to the systematic employment of reason in determining the appearances of our soul. For no empirical laws of bodily appearances, which are of a totally different kind, will then intervene in the explanation of what belongs exclusively to inner sense. No windy hypotheses of generation, extinction, and palingenesis of souls will be permitted. The consideration of this object of inner sense will thus be kept completely pure and will not be confused by the introduction of heterogeneous properties. Also, reason’s investigations will be directed to reducing the grounds of explanation in this field, so far as may be possible, to a single principle. All this will be best attained through such a schema, viewed as if it were a real being; indeed it is attainable in no other way. The psychological idea can signify nothing but the schema of a regulative concept. For were I to enquire whether the soul in itself is of spiritual nature, the question would have no meaning. In employing such a concept I not only abstract from corporeal nature, but from nature in general, that is, from all predicates of any possible experience, and therefore from all conditions requisite for thinking an object for such a concept; yet only as related to an object can the concept be said to have a meaning.

The second regulative idea of merely speculative reason is the concept of the world in general. For nature is properly the only given object in regard to which reason requires regulative principles. This nature is twofold, either thinking or corporeal. To think the latter, so far as regards its inner possibility, that is, to determine the application of the categories to it, we need no idea, that is, no representation which transcends experience. Nor, indeed, is any idea possible in this connection, since in dealing with corporeal nature we are guided solely by sensible intuition. The case is different from that of the fundamental psychological concept (‘I’), which contains a priori a certain form of thought, namely, the unity of thought. There therefore remains for pure reason nothing but nature in general, and the completeness of the conditions in nature in accordance with some principle. The absolute totality of the series of these conditions, in the derivation of their members, is an idea which can never be completely realised in the empirical employment of reason, but which yet serves as a rule that prescribes how we ought to proceed in dealing with such series, namely, that in explaining appearances, whether in their regressive or in their ascending order, we ought to treat the series as if it were in itself infinite, that is, as if it proceeded in indefinitum. When, on the other hand, reason is itself regarded as the determining cause, as in [the sphere of] freedom, that is to say, in the case of practical principles, we have to proceed as if we had before us an object, not of the senses, but of the pure understanding. In this practical sphere the conditions are no longer in the series of appearances; they can be posited outside the series, and the series of states can therefore be regarded as if it had an absolute beginning, through an intelligible cause. All this shows that the cosmological ideas are nothing but simply regulative principles, and are very far from positing, in the manner of constitutive principles, an actual totality of such series. The fuller treatment of this subject will be found in the chapter on the antinomy of pure reason.

The third idea of pure reason, which contains a merely relative supposition of a being that is the sole and sufficient cause of all cosmological series, is the idea of God. We have not the slightest ground to assume in an absolute manner (to suppose in itself) the object of this idea; for what can enable us to believe in or assert a being of the highest perfection and one absolutely necessary by its very nature, merely on the basis of its concept, or if we did how could we justify our procedure? It is only by way of its relation to the world that we can attempt to establish the necessity of this supposition; and it then becomes evident that the idea of such a being, like all speculative ideas, seeks only to formulate the command of reason, that all connection in the world be viewed in accordance with the principles of a systematic unity—as if all such connection had its source in one single all-embracing being, as the supreme and all-sufficient cause. It is thus evident that reason has here no other purpose than to prescribe its own formal rule for the extension of its empirical employment, and not any extension beyond all limits of empirical employment. Consequently it is evident that this idea does not, in any concealed fashion, involve any principle that claims, in its application to possible experience, to be constitutive in character.

This highest formal unity, which rests solely on concepts of reason, is the purposive unity of things. The speculative interest of reason makes it necessary to regard all order in the world as if it had originated in the purpose of a supreme reason. Such a principle opens out to our reason, as applied in the field of experience, altogether new views as to how the things of the world may be connected according to teleological laws, and so enables it to arrive at their greatest systematic unity. The assumption of a supreme intelligence, as the one and only cause of the universe, though in the idea alone, can therefore always benefit reason and can never injure it. Thus if, in studying the shape of the earth (which is round, but somewhat flattened), of the mountains, seas, etc., we assume it to be the outcome of wise purposes on the part of an Author of the world, we are enabled to make in this way a number of discoveries. And provided we restrict ourselves to a merely regulative use of this principle, even error cannot do us any serious harm. For the worst that can happen would be that where we expected a teleological connection (nexus finalis), we find only a mechanical or physical connection (nexus effectivus). In such a case, we merely fail to find the additional unity; we do not destroy the unity upon which reason insists in its empirical employment. But even a disappointment of this sort cannot affect the teleological law itself, in its general bearing. For although an anatomist can be convicted of error when he assigns to some member of an animal body an end which it can be clearly shown not to subserve, it is yet quite impossible to prove in any given case that an arrangement of nature, be it what it may, subserves no end whatsoever. Accordingly, medical physiology extends its very limited empirical knowledge of the ends served by the articulation of an organic body, by resorting to a principle for which pure reason has alone been responsible; and it carries this principle so far as to assume confidently, and with general approval, that everything in an animal has its use, and subserves some good purpose. If this assumption be treated as constitutive it goes much further than observation has thus far been able to justify; and we must therefore conclude that it is nothing more than a regulative principle of reason, to aid us in securing the highest possible systematic unity, by means of the idea of the purposive causality of the supreme cause of the world—as if this being, as supreme intelligence, acting in accordance with a supremely wise purpose, were the cause of all things.

If, however, we overlook this restriction of the idea to a merely regulative use, reason is led away into mistaken paths. For it then leaves the ground of experience, which alone can contain the signs that mark out its proper course, and ventures out beyond it to the incomprehensible and unsearchable, rising to dizzy heights where it finds itself entirely cut off from all possible action in conformity with experience.

The first error which arises from our using the idea of a supreme being in a manner contrary to the nature of an idea, that is, constitutively, and not regulatively only, is the error of ignava ratio. We may so entitle every principle which makes us regard our investigation into nature, on any subject, as absolutely complete, disposing reason to cease from further enquiry, as if it had entirely succeeded in the task which it had set itself. Thus the psychological idea, when it is employed as a constitutive principle to explain the appearances of our soul, and thereby to extend our knowledge of the self beyond the limits of experience (its state after death), does indeed simplify the task of reason; but it interferes with, and entirely ruins, our use of reason in dealing with nature under the guidance of our experiences. The dogmatic spiritualist explains the abiding and unchanging unity of a person throughout all change of state, by the unity of the thinking substance, of which, as he believes, he has immediate perception in the ‘I’; or he explains the interest which we take in what can happen only after our death, by means of our consciousness of the immaterial nature of the thinking subject; and so forth. He thus dispenses with all empirical investigation of the cause of these inner appearances, so far as that cause is to be found in physical grounds of explanation; and to his own great convenience, though at the sacrifice of all real insight, he professes, in reliance upon the assumed authority of a transcendent reason, to have the right to ignore those sources of knowledge which are immanent in experience. These detrimental consequences are even more obvious in the dogmatic treatment of our idea of a supreme intelligence, and in the theological system of nature (physico-theology) which is falsely based upon it. For in this field of enquiry, if instead of looking for causes in the universal laws of material mechanism, we appeal directly to the unsearchable decree of supreme wisdom, all those ends which are exhibited in nature, together with the many ends which are only ascribed by us to nature, make our investigation of the causes a very easy task, and so enable us to regard the labour of reason as completed, when, as a matter of fact, we have merely dispensed with its employment—an employment which is wholly dependent for guidance upon the order of nature and the series of its alterations, in accordance with the universal laws which they are found to exhibit. This error can be avoided, if we consider from the teleological point of view not merely certain parts of nature, such as the distribution of land, its structure, the constitution and location of the mountains, or only the organisation of the vegetable and animal kingdoms, but make this systematic unity of nature completely universal, in relation to the idea of a supreme intelligence. For we then treat nature as resting upon a purposiveness, in accordance with universal laws, from which no special arrangement is exempt, however difficult it may be to establish this in any given case. We then have a regulative principle of the systematic unity of teleological connection—a connection which we do not, however, predetermine. What we may presume to do is to follow out the physico-mechanical connection in accordance with universal laws, in the hope of discovering what the teleological connection actually is. In this way alone can the principle of purposive unity aid always in extending the employment of reason in reference to experience, without being in any instance prejudicial to it.

The second error arising from the misapprehension of the above principle of systematic unity is that of perversa ratio (ὕστερον πρότερον). The idea of systematic unity should be used only as a regulative principle to guide us in seeking for such unity in the connection of things, according to universal laws of nature; and we ought, therefore, to believe that we have approximated to completeness in the employment of the principle only in proportion as we are in a position to verify such unity in empirical fashion—a completeness which is never, of course, attainable. Instead of this the reverse procedure is adopted. The reality of a principle of purposive unity is not only presupposed but hypostatised; and since the concept of a supreme intelligence is in itself completely beyond our powers of comprehension, we proceed to determine it in an anthropomorphic manner, and so to impose ends upon nature, forcibly and dictatorially, instead of pursuing the more reasonable course of searching for them by the path of physical investigation. And thus teleology, which is intended to aid us merely in completing the unity of nature in accordance with universal laws, not only tends to abrogate such unity, but also prevents reason from carrying out its own professed purpose, that of proving from nature, in conformity with these laws, the existence of a supreme intelligent cause. For if the most complete purposiveness cannot be presupposed a priori in nature, that is, as belonging to its essence, how can we be required to search for it, and through all its gradations to approximate to the supreme perfection of an Author of all things, a perfection that, as absolutely necessary, must be knowable a priori The regulative principle prescribes that systematic unity as a unity in nature, which is not known merely empirically but is presupposed a priori (although in an indeterminate manner), be presupposed absolutely, and consequently as following from the essence of things. If, however, I begin with a supreme purposive being as the ground of all things, the unity of nature is really surrendered, as being quite foreign and accidental to the nature of things, and as not capable of being known from its own universal laws. There then arises a vicious circle; we are assuming just that very point which is mainly in dispute.

To take the regulative principle of the systematic unity of nature as being a constitutive principle, and to hypostatise, and presuppose as a cause, that which serves, merely in idea, as the ground of the consistent employment of reason, is simply to confound reason. The investigation of nature takes its own independent course, keeping to the chain of natural causes in conformity with their universal laws. It does indeed, in so doing, proceed in accordance with the idea of an Author of the universe, but not in order to deduce therefrom the purposiveness for which it is ever on the watch, but in order to obtain knowledge of the existence of such an Author from this purposiveness. And by seeking this purposiveness in the essence of the things of nature, and so far as may be possible in the essence of things in general, it seeks to know the existence of this supreme being as absolutely necessary. Whether this latter enterprise succeed or not, the idea remains always true in itself, and justified in its use, provided it be restricted to the conditions of a merely regulative principle.

Complete purposive unity constitutes what is, in the absolute sense, perfection. If we do not find this unity in the essence of the things which go to constitute the entire object of experience, that is, of all our objectively valid knowledge, and therefore do not find it in the universal and necessary laws of nature, how can we profess to infer directly from this unity the idea of a supreme and absolutely necessary perfection of an original being, as the source of all causality? The greatest possible systematic unity, and consequently also purposive unity, is the training school for the use of reason, and is indeed the very foundation of the possibility of its greatest possible employment. The idea of such unity is, therefore, inseparably bound up with the very nature of our reason. This same idea is on that account legislative for us; and it is therefore very natural that we should assume a corresponding legislative reason (intellectus archetypus), from which, as the object of our reason, all systematic unity of nature is to be derived.

In discussing the antinomy of pure reason we have stated that the questions propounded by pure reason must in every case admit of an answer, and that in their regard it is not permissible to plead the limits of our knowledge (a plea which in many questions that concern nature is as unavoidable as it is relevant). For we are not here asking questions in regard to the nature of things, but only such questions as arise from the very nature of reason, and which concern solely its own inner constitution. We are now in a position to confirm this assertion—which at first sight may have appeared rash—so far as regards the two questions in which pure reason is most of all interested; and thus finally to complete our discussion of the dialectic of pure reason.

If, in connection with a transcendental theology, we ask, first, whether there is anything distinct from the world, which contains the ground of the order of the world and of its connection in accordance with universal laws, the answer is that there undoubtedly is. For the world is a sum of appearances; and there must therefore be some transcendental ground of the appearances, that is, a ground which is thinkable only by the pure understanding. If, secondly, the question be, whether this being is substance, of the greatest reality, necessary, etc., we reply that this question is entirely without meaning. For all categories through which we can attempt to form a concept of such an object allow only of empirical employment, and have no meaning whatsoever when not applied to objects of possible experience, that is, to the world of sense. Outside this field they are merely titles of concepts, which we may admit, but through which [in and by themselves] we can understand nothing. If, thirdly, the question be, whether we may not at least think this being, which is distinct from the world, in analogy with the objects of experience, the answer is: certainly, but only as object in idea and not in reality, namely, only as being a substratum, to us unknown, of the systematic unity, order, and purposiveness of the arrangement of the world—an idea which reason is constrained to form as the regulative principle of its investigation of nature. Nay, more, we may freely, without laying ourselves open to censure, admit into this idea certain anthropomorphisms which are helpful to the principle in its regulative capacity. For it is always an idea only, which does not relate directly to a being distinct from the world, but to the regulative principle of the systematic unity of the world, and only by means of a schema of this unity, namely, through the schema of a supreme intelligence which, in originating the world, acts in accordance with wise purposes. What this primordial ground of the unity of the world may be in itself, we should not profess to have thereby decided, but only how we should use it, or rather its idea, in relation to the systematic employment of reason in respect of the things of the world.

But the question may still be pressed: Can we, on such grounds, assume a wise and omnipotent Author of the world? Undoubtedly we may; and we not only may, but must, do so. But do we then extend our knowledge beyond the field of possible experience? By no means. All that we have done is merely to presuppose a something, a merely transcendental object, of which, as it is in itself, we have no concept whatsoever. It is only in relation to the systematic and purposive ordering of the world, which, if we are to study nature, we are constrained to presuppose, that we have thought this unknown being by analogy with an intelligence (an empirical concept); that is, have endowed it, in respect of the ends and perfection which are to be grounded upon it, with just those properties which, in conformity with the conditions of our reason, can be regarded as containing the ground of such systematic unity. This idea is thus valid only in respect of the employment of our reason in reference to the world. If we ascribed to it a validity that is absolute and objective, we should be forgetting that what we are thinking is a being in idea only; and in thus taking our start from a ground which is not determinable through observation of the world, we should no longer be in a position to apply the principle in a manner suited to the empirical employment of reason.

But, it will still be asked, can I make any such use of the concept and of the presupposition of a supreme being in the rational consideration of the world? Yes, it is precisely for this purpose that reason has resorted to this idea. But may I then proceed to regard seemingly purposive arrangements as purposes, and so derive them from the divine will, though, of course, mediately through certain special natural means, themselves established in furtherance of that divine will? Yes, we can indeed do so; but only on condition that we regard it as a matter of indifference whether it be asserted that divine wisdom has disposed all things in accordance with its supreme ends, or that the idea of supreme wisdom is a regulative principle in the investigation of nature and a principle of its systematic and purposive unity, in accordance with universal laws, even in those cases in which we are unable to detect that unity. In other words, it must be a matter of complete indifference to us, when we perceive such unity, whether we say that God in his wisdom has willed it to be so, or that nature has wisely arranged it thus. For what has justified us in adopting the idea of a supreme intelligence as a schema of the regulative principle is precisely this greatest possible systematic and purposive unity—a unity which our reason has required as a regulative principle that must underlie all investigation of nature. The more, therefore, we discover purposiveness in the world, the more fully is the legitimacy of our idea confirmed. But since the sole aim of that principle was to guide us in seeking a necessary unity of nature, and that in the greatest possible degree, while we do indeed, in so far as we attain that unity, owe it to the idea of a supreme cannot, without contradicting ourselves, nore the universal laws of nature—with a view to discovering which the idea was alone adopted—and look upon this purposiveness of nature as contingent and hyperphysical in its origin. For we were not justified in assuming above nature a being with those qualities, but only in adopting the idea of such a being in order to view the appearances as systematically connected with one another in accordance with the principle of a causal determination.

For the same reasons, in thinking the cause of the world, we are justified in representing it in our idea not only in terms of a certain subtle anthropomorphism (without which we could not think anything whatsoever in regard to it), namely, as a being that has understanding, feelings of pleasure and displeasure, and desires and volitions corresponding to these, but also in ascribing to it a perfection which, as infinite, far transcends any perfection that our empirical knowledge of the order of the world can justify us in attributing to it. For the regulative law of systematic unity prescribes that we should study nature as if systematic and purposive unity, combined with the greatest possible manifoldness, were everywhere to be met with, in infinitum. For although we may succeed in discovering but little of this perfection of the world, it is nevertheless required by the legislation of our reason that we must always search for and surmise it; and it must always be beneficial, and can never be harmful, to direct our investigations into nature in accordance with this principle. But it is evident that in this way of representing the principle as involving the idea of a supreme Author, I do not base the principle upon the existence and upon the knowledge of such a being, but upon its idea only, and that I do not really derive anything from this being, but only from the idea of it—that is, from the nature of the things of the world, in accordance with such an idea. A certain, unformulated consciousness of the true use of this concept of reason seems indeed to have inspired the modest and reasonable language of the philosophers of all times, since they speak of the wisdom and providence of nature and of divine wisdom, just as if nature and divine wisdom were equivalent expressions—indeed, so long as they are dealing solely with speculative reason, giving preference to the former mode of expression, on the ground that it enables us to avoid making profession of more than we are justified in asserting, and that it likewise directs reason to its own proper field, namely, nature.

Thus pure reason, which at first seemed to promise nothing less than the extension of knowledge beyond all limits of experience, contains, if properly understood, nothing but regulative principles, which, while indeed prescribing greater unity than the empirical employment of understanding can achieve, yet still, by the very fact that they place the goal of its endeavours at so great a distance, carry its agreement with itself, by means of systematic unity, to the highest possible degree. But if, on the other hand, they be misunderstood, and be treated as constitutive principles of transcendent knowledge, they give rise, by a dazzling and deceptive illusion, to persuasion and a merely fictitious knowledge, and therewith to contradictions and eternal disputes.

Thus all human knowledge begins with intuitions, proceeds from thence to concepts, and ends with ideas. Although in respect of all three elements it possesses a priori sources of knowledge, which on first consideration seem to scorn the limits of all experience, a thoroughgoing critique convinces us that reason, in its speculative employment, can never with these elements transcend the field of possible experience, and that the proper vocation of this supreme faculty of knowledge is to use all methods, and the principles of these methods, solely for the purpose of penetrating to the innermost secrets of nature, in accordance with every possible principle of unity—that of ends being the most important—but never to soar beyond its limits, outside which there is for us nothing but empty space. The critical examination, as carried out in the Transcendental Analytic, of all propositions which may seem to extend our knowledge beyond actual experience, has doubtless sufficed to convince us that they can never lead to anything more than a possible experience. Were it not that we are suspicious of abstract and general doctrines, however clear, and were it not that specious and alluring prospects tempt us to escape from the compulsion which these doctrines impose, we might have been able to spare ourselves the laborious interrogation of all those dialectical witnesses that a transcendent reason brings forward in support of its pretensions. For we should from the start have known with complete certainty that all such pretensions, while perhaps honestly meant, must be absolutely groundless, inasmuch as they relate to a kind of knowledge to which man can never attain. But there is no end to such discussions, unless we can penetrate to the true cause of the illusion by which even the wisest are deceived. Moreover, the resolution of all our transcendent knowledge into its elements (as a study of our inner nature) is in itself of no slight value, and to the philosopher is indeed a matter of duty. Accordingly, fruitless as are all these endeavours of speculative reason, we have none the less found it necessary to follow them up to their primary sources. And since the dialectical illusion does not merely deceive us in our judgments, but also, because of the interest which we take in these judgments, has a certain natural attraction which it will always continue to possess, we have thought it advisable, with a view to the prevention of such errors in the future, to draw up in full detail what we may describe as being the records of this lawsuit, and to deposit them in the archives of human reason.