CONCLUSION.
On the determination of the boundary of the Pure Reason.
§ 57.
After all the very clear proofs we have above given, it would be absurd for us to expect to cognise more in any object than what belongs to its possible experience, or to lay claim to the least knowledge of anything whatever which would determine its constitution in itself, unless we assume it to be an object of possible experience. For wherewith shall we effect this determination, inasmuch as time, space, and all the conceptions of the understanding, and still more the conceptions derived from empirical intuition or perception in the sense-world would neither have nor could have any other use than merely to make experience possible, and when if we leave out this condition from the pure conceptions of the understanding, they determine no object whatever, and have no significance anywhere [?].
But it would be a still greater absurdity for us not to admit things in themselves at all, or to wish to give out our experience for the only possible mode of the cognition of objects, in other words, our intuition in space and time for the only possible intuition, and our discursive understanding for the model of every possible understanding, thereby wishing principles of the possibility of experience to be held for the universal conditions of things in themselves.
Our principles, which limit the use of the Reason to possible experience, might accordingly become transcendent, and the limits of our Reason be given out for the limits of things themselves, of which Hume’s Dialogues may serve as an example, if a careful Critique of the boundaries of our Reason did not keep watch on its empirical use, and set a limit to its pretensions. Scepticism originally arose from metaphysics and its anarchical (Polizeilosen) dialectic. At first, to favour the empirical use of the understanding, it might well give out for nugatory and deceptive all that exceeded this; but gradually, as it became evident that the very same principles which we make use of in experience are à priori, and that they led unobserved, and as it seemed with the same right, still farther than experience reaches, a doubt began to be thrown on the principles of experience themselves. Now as to these there is no danger, for herein a healthy understanding will always assert its rights; but there arose a special confusion in science, which could not determine how far, and why only thus far and no farther, the Reason is to be trusted; but this confusion can only be got rid of, and any future relapse prevented, by a formal limitation of the use of our Reason, derived from principles. It is true we cannot form any definite conception of what things in themselves, beyond all possible experience, may be. But we are nevertheless not free to withdraw ourselves wholly from the inquiry as to these; for experience never fully suffices for the Reason; it thrusts us ever farther and farther back for the answer to this question, and leaves us as regards its complete solution dissatisfied; as any one can see from the dialectic of the pure Reason, which on this account has its valid subjective ground. Who can tolerate [the circumstance] that by the nature of our soul we can attain to the clear consciousness of the subject, and to the conviction that its phenomena cannot be explained materialistically without asking what the soul really is, and if no empirical conception suffices [to explain] this, at least assuming a conception of the Reason (of a simple immaterial essence) merely for the above purpose, although we cannot demonstrate its objective reality in any way? Who can satisfy himself in all cosmological questions, as to the size and duration of the world, of freedom or natural necessity, with mere empirical knowledge, since, begin it as we will, every answer given according to the fundamental laws of experience, gives birth to a new question, just as much requiring an answer, and thereby clearly exposing the inadequacy of all physical modes of explanation for the satisfaction of the Reason? Finally, who in the face of the thoroughgoing contingency and dependence of all that he can assume and think according to empirical principles, does not see the impossibility of taking his stand on these, and does not feel himself necessarily impelled, in spite of all prohibition against losing himself in transcendent ideas, to seek rest and satisfaction beyond all conceptions he can verify by experience, in that of a Being, of whom the possibility of the idea in itself cannot indeed be apprehended, but which cannot be refuted, because it is a mere being [essence] of the understanding, and without which the Reason must remain for ever unsatisfied.
Boundaries (with extended beings) always presuppose a space, met with, outside a certain definite place, and enclosing it. Limits do not require this, being mere negations affecting a quantity, so far as it has no absolute completeness. Our Reason, however, sees around it as it were a space for the cognition of things in themselves, although it can never have definite conceptions of them, being limited to phenomena.
As long as the cognition of the Reason is homogeneous, no definite boundaries can be conceived therein. In mathematics and natural science the human Reason recognises indeed limits but no boundaries, i.e., [it recognises] that something exists outside itself, to which it can never attain, but not that it can itself be anywhere terminated in its inner progress. The extension of our views in mathematics and the possibility of new inventions reaches to infinity; and the same can be said of the discovery of new qualities in Nature, and of new forces and laws, through continued experience and the union of the same by the Reason. But, at the same time, it cannot be mistaken that there are limits here, for mathematics refers only to phenomena, and what cannot be an object of sensuous intuition, such as the conceptions of metaphysics and morals, lies wholly outside its sphere, [in a region] to which it can never lead, and which does not at all require it. There is, then, a continuous progress and approach to these sciences, and as it were a point or line of contact. Natural science will never discover for us the inner [nature] of things, namely, that which is not phenomenon, but which can still serve as the highest ground of the explanation of phenomena. But it does not require this for its physical explanations; nay, if such were offered it from another source (e.g., the influence of immaterial beings), it ought to reject it, and on no account to bring it into the course of its explanations, but invariably to base these on that which pertains to experience as object of sense, and which can be brought into connection with our real perceptions, and empirical laws.
But metaphysics leads us to boundaries in the dialectical attempts of the pure Reason (which are not commenced arbitrarily or rashly, but to which the nature of the Reason itself urges us), and the transcendental ideas, as we cannot have intercourse with them, and as they will never allow themselves to be realised, serve, not only to show us the actual boundaries of the use of the pure Reason, but also the way to determine them. And this is also the end and use of this natural disposition of our Reason, which has given birth to metaphysics as its pet child, whose generation, like that of everything else in the world, is not to be ascribed to chance, but to an original germ, wisely organised for great ends. For metaphysics is, perhaps more than any other science, rooted in us in its fundamental features by Nature herself, and can by no means be regarded as the product of a voluntary choice or as chance extension in the progress of experiences (from which it is wholly divided).
The Reason, though all its conceptions and laws of the understanding are adequate in the sense-world, does not find any satisfaction for itself in them, for it is deprived of all hope of a complete solution by questions recurring ad infinitum. The transcendental ideas which have this completion for an object are such problems of the Reason. It sees clearly that the sense-world cannot contain the completeness [required], and therefore just as little can those conceptions which serve simply to the understanding of the same, namely, space and time, and all that we have adduced under the name of pure conceptions of the understanding. The sense-world is nothing but a chain of phenomena, connected according to universal laws, and has therefore no subsistence for itself, being not properly the thing in itself, and only being necessarily referable to that which contains the ground of this phenomenon, to essences that cannot be cognised merely as phenomena but as things in themselves. Only in the cognition of these can Reason hope to see its desire for completeness in the progress from the conditioned to its conditions, once for all satisfied.
We have above (§§ 33, 34) assigned the limits of the Reason in respect of all cognition of mere essences of thought. Now, as the transcendental ideas make the progress up to these necessary, and have thus led us, as it were, to the contact of the full space (of experience) with the void of which we know nothing (to the noumena), we can determine the boundaries of the pure Reason. For in all boundaries there is something positive (for instance surface is the boundary of corporeal space and yet is itself a space; line, a space which is the boundary of the surface; point, the boundary of the line, but still [occupying] a position in space), while, on the other hand, limits contain mere negations. The limits assigned in the paragraph cited, are not sufficient, after we have found that something lies beyond them (although we can never know what this may be in itself). For the question is now, what is the attitude of our Reason in this connection of that which we know, with that which we do not know, and never can know? Here is a real connection of the known with a wholly unknown (and something that will always remain unknown), and even if in this the unknown should not become in the least [degree] more known—which is indeed not to be expected—the conception of this connection must be able, notwithstanding, to be determined and reduced to distinctness.
We are obliged, then, to think of an immaterial essence, an intelligible world, and a highest of all beings (mere noumena), because only in these, as things in themselves, does the Reason meet with the completeness and satisfaction it can never hope for from the derivation of phenomena from their homogeneous ground, because they really refer to something distinct from the latter (and therefore wholly heterogeneous), inasmuch as phenomena always presuppose a thing in itself, and indicate this, [it matters not] whether we may know it more closely or not.
But as we can never know these essences of the understanding as to what they may be in themselves, that is, determinately, but are obliged nevertheless to assume such in relation to the sense-world, and to connect them with it through the Reason, we shall be at least able to cogitate this connection by means of such conceptions as express its relation to the sense-world. For if we cogitate the essence of the understanding, through nothing but pure conceptions of the understanding, we really cogitate thereby nothing definite, and our conception is consequently without meaning; if we cogitate it through qualities borrowed from the sense-world, then it is no longer an essence of the understanding, but is conceived as one of the phenomena, and belongs to the sense-world. We will take an instance from the conception of the Supreme Being.
The deistic conception is an entirely pure conception of the Reason, which, however, only represents a thing containing all reality, without our being able to determine a single one of its [qualities], because for this an instance would have to be borrowed from the sense-world, in which case I should always have to do with an object of sense, and not with something completely heterogeneous, and which cannot be an object of sense. For instance, I attribute understanding to it; but I have no conception whatever of any understanding but of one like my own, namely, of one to which intuitions must be given through the senses, and which occupies itself with reducing these under rules of the unity of the consciousness. But then the elements of my conception would always lie in the phenomenon; yet I was necessitated by the inadequacy of the phenomena to pass beyond this, to the conception of a being in no way dependent on phenomena, or bound up with them, as conditions of its determination. If, however, I sever the understanding from the sensibility in order to have a pure understanding, nothing remains over but the mere form of thought without intuition, by means of which I can cognise nothing determinate as object. For this purpose I should have to conceive another understanding which intuited objects, but of which I have not the least conception, because the human understanding is discursive and can only cognise through universal conceptions. But I am also involved in contradiction if I attribute will to the Supreme Being. For I have this conception only in so far as I derive it from my inner experience, and thereby from the dependence of my satisfaction from objects whose existence we require; but at the foundation of this lies sensibility, which wholly contradicts the pure conception of the Supreme Being. The objections of Hume to Deism are weak, touching no more than the proofs, and never the proposition of the deistic assertion itself. But as regards Theism, which must be arrived at by a closer determination of our, there [viz., in Deism], merely transcendent conception of the Supreme Being, they are very strong, and, according as the conception is constructed, in certain (indeed in all ordinary) cases are irrefragable. Hume always insists, that through the mere conception of an original being, to whom we can attribute none but ontological predicates (eternity, omnipresence, omnipotence) we really think nothing definite, but that qualities expressing an object in concreto must be superadded. It is not enough to say it is Cause, but [we must also say] what is the nature of its causality, as, whether [it operates] through understanding and will; and at this point his attacks on the thing itself, namely, on Theism, commence, whereas before he had only stormed the grounds of proof of Deism, which does not carry any especial danger with it. His dangerous arguments refer entirely to anthropomorphism, which he holds to be inseparable from Theism, and to make it contradictory in itself; while if this be left out, [Theism itself] would also fall, and nothing would remain but a Deism wherewith nothing could be done, which could not avail us for anything, and could not serve as a foundation for religion and morals. If this inevitability of anthropomorphism were certain, the proofs of the existence of a Supreme Being might be what one liked, and all conceded, yet the conception of this Being would never be able to be determined by us, without involving ourselves in contradictions.
But if with the injunction to avoid all transcendent judgments of the pure Reason, we connect the apparently contradictory injunction to proceed to conceptions lying outside the field of its immanent (empirical) use, we shall be aware that both may subsist together, but only on the exact boundary of all admissible use of the Reason; for this belongs as much to the field of experience as to that of essences of thought, and we shall be taught thereby, at the same time, how the above remarkable ideas serve simply, for the determination of the boundaries of the human Reason; namely, on the one hand not to extend cognition of experience in an unbounded manner, so that nothing but mere world remains for us to cognise, and on the other hand not to pass beyond the boundaries of experience, or to seek to judge of things outside the latter as things in themselves.
But we keep to this boundary when we limit our judgment to the relation the world may have to a Being, whose conception itself lies outside all the cognition of which we are capable within the world. For in this case, we do not attribute to the Supreme Being any of the qualities in themselves by which we cogitate objects of experience, and thereby avoid the dogmatic anthropomorphism; but we apply the relations of the same to the world, and thereby allow ourselves a symbolical anthropomorphism, which as a matter of fact only concerns the language and not the object.
When I say we are obliged to regard the world as though it were the work of a supreme understanding and will, I do not really say more than—as a watch, a ship, a regiment is related to the artisan, shipbuilder or general, so is the sense-world (or all that which constitutes the foundation of this sum-total of phenomena) [related] to the unknown, that I cognise, not indeed according to what it is in itself, but according to what it is for me, namely, in respect of the world, of which I am a part.
§ 58.
Such a cognition as this is one according to analogy, which does not signify an imperfect resemblance of two things, as the word is commonly taken [to mean], but a perfect resemblance of two relations between totally dissimilar things. By means of this analogy a, for us, adequately defined conception of the Supreme Being remains, although we have left out everything that could determine it simply, and in itself; for we define it as regards the world, and therefore as regards ourselves, and more is not necessary for us. The attacks Hume makes on those who would define this conception absolutely, in that they borrow the materials from themselves and from the world, do not affect us; and moreover he cannot reproach us that there remains nothing over, after the objective anthropomorphism of the conception of the Supreme Being is taken away.
For at the outset, let the deistic conception of an original Being be conceded us as a necessary hypothesis (as Hume does in his Dialogues, in the person of Philo against Cleanthes), in which the original Being is conceived through purely ontological predicates, of substance, cause, &c. This must be done, because the Reason is impelled in the sense-world by mere conditions, which are themselves again conditioned, without the possibility of any satisfaction; it can also be very well done, without lapsing into anthropomorphism, which transfers predicates from the sense-world to a Being quite distinct from the world, inasmuch as these predicates [in our case] are mere categories, affording no definite [conception at all], and hence no conception of it limited to conditions of the sensibility. Nothing can hinder us, therefore, from predicating of this Being a causality through Reason in respect of the world, and so from passing over to Theism without being obliged to attribute to it this Reason, as a quality attaching to it in itself. For as regards the first point, the only possible way of pursuing the use of the Reason in respect of all possible experience in the sense-world, to its highest extent and in thorough agreement with itself, is when a supreme Reason is assumed as a cause of all connections in the world. Such a principle must be throughout advantageous to it, and can never injure it in its natural use. But secondly, the Reason is not transferred as a quality to the original Being in itself, but only in its relation to the sense-world, and thus anthropomorphism is altogether avoided. For here, only the cause of the form of Reason everywhere met with in the world is considered, and to the Supreme Being, so far as it is the ground of this form of Reason in the world, Reason is attributed, but only on the principle of analogy, i.e., in so far as this expression [viz., Reason] indicates what the, to us, unknown ultimate cause of the world has wherewith to determine all things therein, in the highest degree, in accordance with Reason. In this we take care to make use of the quality of Reason, not by its means to conceive God, but [rather] the world, as it is necessary to have the greatest possible use of the Reason in respect of the latter [determined] according to a principle. We confess thereby that the Supreme Being, as to what it may be in itself, is entirely impenetrable to us, and is even unthinkable in a definite manner, and hence we are prevented from making any transcendent use of our conceptions, derived from the Reason as an efficient cause (by means of the will), for determining the divine nature, by qualities that are only borrowed from human nature, and thus from losing ourselves in gross or chimerical conceptions; but, on the other hand, [we are prevented] from inundating the view of the world, [attained] by our conceptions of the human Reason as transferred to God, with hyperphysical modes of explanation, and thus from degrading it, from its proper destination according to which it ought to be a study of mere Nature through the Reason, and not a presumptuous derivation of its phenomena from a supreme Reason. The expression suited to our feeble conceptions will be that we conceive the world as though it orginated from a supreme Reason, as to its reality and as to its inward determination, by which we partly recognise the constitution belonging to it, the world itself, though without presuming to wish to define its cause in itself; and partly, on the other hand, place the ground of this constitution in the relation of the supreme Cause to the world ([viz.] to the form of Reason in the world), without finding the world adequate for this purpose by itself.
In this way the difficulties seeming to oppose Theism vanish, in that to the principle of Hume, not to push the use of the Reason dogmatically beyond all possible experience, another principle is united, completely overlooked by Hume, namely, not to mistake the field of possible experience for that which bounds itself in the eye of our Reason. Critique of Reason here signifies the true middle path between the dogmatism Hume combated, and the scepticism he would have introduced in its place, a middle path which is unlike other middle paths that attempt to determine themselves as it were mechanically (by taking something from one and something from another), and by which no one is taught a better way, but one, such as can be determined accurately, according to principles.
§ 59.
I have made use of the metaphor of a boundary at the commencement of this observation, in order to fix the limits of the Reason in respect of its appropriate use. The sense-world contains merely phenomena, which are not things in themselves, yet the understanding must assume the latter (noumena), for the very reason that it recognises the objects of experience for mere phenomena. In our Reason both are alike included, and the question is: How does the Reason proceed in determining both fields? Experience, which contains all that belongs to the sense-world, is not bounded by itself; it only attains from one conditioned to another conditioned. That which shall bound it must lie wholly outside it, and this is the field of pure essences of the understanding. But this is for us a blank space, in so far as the determination of the nature of these essences of the understanding is concerned, and thus, when we have to do with dogmatically defined conceptions, we cannot pass beyond the field of possible experience. But as a boundary is itself something positive, belonging as much to what is within as to the space without a given content, so it is a really positive cognition, in which the Reason merely participates, by extending itself to this boundary, in such wise, that it does not attempt to go beyond the boundary, because it finds a blank space before it, wherein it can indeed cogitate forms to things, but cannot cogitate things themselves. But the bounding of the field of experience by something otherwise unknown to it, is a cognition remaining to the Reason in this standpoint, whereby it is not enclosed within the sense-world, neither is it left dreaming [schwärmend] outside it, but limits itself, as befits the knowledge of a boundary, to the relation of that which lies outside the same, to that which is within it.
Natural theology is a conception of this nature, at the boundary of the human Reason, inasmuch as it sees itself necessitated to look beyond to the idea of the Supreme Being (and in a practical connection, also, to that of an intelligible world), not in order to determine anything in respect of this mere essence of the understanding, in other words, anything outside the world of sense, but to guide itself for its own use within the latter, according to principles of the greatest possible unity (theoretically as well as practically). And for this purpose it makes use of the reference of the same to an independent Reason as the cause of all these connections, thereby not merely inventing a being, but inasmuch as outside the world something must necessarily exist (anzutreffen sein) which only the understanding cogitates, determining it [viz., this being] in the above manner, although only on the principle of analogy.
In this way our original proposition remains, which is the result of the whole Critique: “that our Reason can never teach more by its principles à priori than simply objects of possible experience, and even of these no more than what can be cognised in experience.” But this limitation does not prevent it from leading us to the objective boundary of experience, namely, the reference to something which is not itself object of experience, but is nevertheless the highest ground of all experience, without however teaching us anything respecting this in itself, but only with reference to its [viz., the Reason’s] own complete use as directed to its highest end, within the field of possible experience. But this is also all the use that can be reasonably expected or even wished, as concerns it, and with this we have cause to be content.
§ 60.
Thus we have fully exhibited metaphysics according to its subjective necessity, as it is really given in the natural disposition of the human Reason, and indeed in what constitutes its essential purpose. We have found in the course of this investigation, that such a merely natural use of such a disposition of our Reason involves us in extravagant dialectical conclusions, partly apparently, and partly really, conflicting [with one another], if no discipline bridles it and keeps it within limits, which is only possible by means of scientific criticism. And, in addition, [we have found] this fallacious metaphysics to be dispensable to the promotion of the knowledge of Nature, and even prejudicial to it. It always remains, notwithstanding, a task worthy of research, to find out the natural ends aimed at by this disposition in our Reason to transcendent conceptions, since everything in Nature must have been originally designed for some useful purpose.
Such an investigation is here out of place; I confess, moreover, that all I here say respecting the primary ends of Nature is only conjecture, but which may be permitted me in this case, as the question does not concern the objective validity of metaphysical judgments, but refers merely to the natural disposition to the latter, and thus lies outside the system of metaphysics, in that of anthropology.
When I compare all transcendental ideas whose content constitutes the special problem of the natural, pure Reason, compelling it to leave the mere contemplation of Nature and to pass beyond all possible experience, and in this endeavour to produce the thing (be it knowledge or nonsense) called metaphysics, I believe myself to have discovered that this natural disposition is intended to free our conceptions from the chains of experience and the limits of the mere contemplation of Nature, in so far that it may at least see a field opened before it, containing mere objects for the pure Reason, which cannot be arrived at by any sensibility. The purpose is not, indeed, to occupy ourselves speculatively with these objects, (because we can find no firm ground for our feet), but because practical principles, without finding such a space before them for their necessary expectation and hope, could not expand themselves to the universality, the Reason indispensably requires, from a moral point of view.
Now, I find that the psychological idea, however little may be the insight I obtain by its means into the pure nature of the human soul, which is raised above all conceptions of experience, at least sufficiently shows me the inadequacy of the latter, and thereby preserves me from materialism as being a psychological conception of no avail for the explanation of Nature, and besides, as narrowing the Reason in its practical aspect. In the same way the cosmological ideas, by the obvious inadequacy of all possible knowledge of Nature to satisfy the Reason in its justifiable inquiries, serve to keep us from the Naturalism which proclaims Nature for self-sufficing. Finally, as all natural necessity in the sense-world is invariably conditioned, inasmuch as it always presupposes dependence of things on one another, and, as unconditioned necessity must be sought for in the unity of a Cause separate from the sense-world, (but the causality of which, if it were mere Nature, could yet never render comprehensible the existence of the contingent as its consequence;) [this being so,] the Reason frees itself by means of the theological idea from fatalism, as well from that of a blind natural necessity in the coherence of Nature, without a first principle, as in the causality of this principle itself, and leads to the conception of a cause through freedom, in other words, a supreme intelligence. Thus the transcendental ideas serve, if not to instruct us positively, at least to do away with the audacious assertions of materialism, naturalism, and fatalism, which narrow the field of the Reason, and thereby to procure a place for moral ideas outside the region of speculation; and this, as it seems to me, will in some measure explain the above natural disposition.
The practical utility a merely speculative science may have, lies outside the boundaries of this science, and hence can be merely viewed as a scholium, and, like all scholia, not as forming a part of the science itself. At the same time, this reference lies at least within the boundaries of philosophy, especially of that which draws from the sources of pure Reason, where the speculative use of the Reason in metaphysics must have a necessary unity with its practical use in morals. Hence the unavoidable dialectic of the pure Reason in metaphysics must be considered as natural disposition—not merely as an illusion requiring to be resolved, but as a natural institution, as concerns its end—deserving, if possible, to be explained, although this task, being supererogatory, cannot in justice be claimed of metaphysics proper.
As a second scholium, more related to the content of metaphysics, the solution of the problems must be regarded which are discussed in the Critique from pp. 410 to 432. For certain principles of Reason are there expounded, determining the order of Nature, or rather the understanding, which is to seek out her laws through experience, à priori. They seem to be constitutive and legislative in respect of experience, whereas they arise from mere Reason, which cannot be regarded like the understanding as a principle of possible experience. Now whether this agreement rests upon the fact that just as Nature is not itself dependent on the phenomena or their source, the sensibility, but only on the relation of the latter to the understanding; so the thorough-going unity of its use, for the sake of a complete possible experience (in a system), can only pertain to this understanding in its relation to the Reason—whether experience, in other words, stand mediately under the legislation of the Reason—[is a question which] may be further considered by those who desire to investigate the nature of the Reason, apart from its use in metaphysics, and to construct a systematic history of Nature upon general principles. This question I have indeed noticed as important in the book itself, although I have not attempted its solution.
And thus I conclude the analytical solution of the problem I had myself proposed—How is metaphysics at all possible? having proceeded from that in which its use is really given, at least in its consequences, to the grounds of its possibility.
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