Section 1. On ideas in general

For all the abundance our languages possess, a thinking mind is often left embarrassed for the very expression that would fit its concept exactly, and lacking which it can render itself, neither to others nor even to itself , properly intelligible. To coin new words is to lay claim to legislating in language—a pretension that rarely succeeds; and before one resorts to so desperate an expedient, the prudent course is to cast about in some dead and learned tongue to discover whether this concept, along with a fitting expression for it, may not already be present there; and even should the old usage of that word have been rendered somewhat wavering through the incaution of those who first framed it, it is still preferable to pin down the meaning that was distinctively its own (granting that it may remain uncertain whether precisely this same sense was intended back then) than to ruin one's enterprise outright by making oneself unintelligible.

For this very reason, should there happen to exist just one solitary word for a given concept—a word that in its already established usage fits that concept exactly, and whose separation from other cognate concepts carries great weight—the sensible thing is not to handle it wastefully, nor to deploy it merely for variety's sake as a synonym for others, but instead to guard carefully its own proper signification; for otherwise it readily comes about that, once the expression ceases to hold our attention in any special way and sinks from view amid the throng of others of widely differing meaning, the very thought is lost as well that it, and it alone, might have preserved.

Plato made use of the term idea in a manner that plainly reveals he meant by it something which is not merely never drawn from the senses, but which even rises far above those concepts of the understanding that engaged Aristotle, seeing that in experience one never lights upon anything congruent with it. For Plato the ideas are archetypes of the things themselves, not merely keys to possible experiences in the way the categories are. On his view they streamed forth from the highest reason, from which they passed to human reason, which, however, no longer stands today in its pristine condition, but must with effort summon back the old ideas, now heavily darkened, by means of a recollection (which is what philosophy is). I do not wish here to embark on any literary inquiry with a view to establishing the sense the sublime philosopher bound up with his expression. I note only that it is nothing whatever out of the ordinary—in everyday talk no less than in written works—to understand an author better than he understood himself, through a comparison of the thoughts he voices about his subject, since he failed to fix his concept adequately and thus at times spoke, or indeed thought, in opposition to his own purpose.

Plato observed quite well that our faculty of cognition feels a need far loftier than merely, in keeping with synthetic unity , to spell appearances out so as to make them legible as experience, and that our reason, of its own nature, lifts itself toward cognitions that reach so far that no object experience is able to supply could ever prove congruent with them—cognitions that for all that possess a reality of their own and are in no way mere fabrications of the brain.

It was above all across the whole domain of the practical that Plato located his ideas,³⁵ that is, in whatever rests upon freedom—freedom that on its side falls under cognitions constituting a distinctive product of reason. Anyone bent on drawing the concepts of virtue out of experience, anyone minded to take what can at most furnish an example for imperfect illustration and set it up as the model for the wellspring of cognition (as, in truth, no small number have done), would turn virtue into an equivocal monstrosity, shifting with time and circumstance and serviceable for no rule whatever. In contrast, everyone becomes inwardly aware that, when someone is set before him as a model of virtue, he yet retains the genuine original solely within his own head, against which he measures this alleged model and by reference to which alone he rates it. This, however, is the idea of virtue, in relation to which all conceivable objects of experience do duty indeed as examples (evidence that what the concept of reason demands is, to some degree, achievable), yet not as archetypes. The fact that no human being will ever conduct himself in a manner fully commensurate with what the pure idea of virtue holds within it does nothing at all to prove there is something chimerical in this thought. For all the same, every judgment upon moral worth or worthlessness is possible only through the mediation of this idea; consequently it lies of necessity at the basis of every advance toward moral perfection, however far the obstacles lodged in human nature—whose magnitude admits of no determination—may keep us at a distance from it.

Plato's Republic has passed into a byword, taken as a glaring specimen of a perfection merely dreamed up, one able to lodge nowhere but in the brain of the idle thinker, and Brucker finds it laughable that the philosopher should have asserted a prince would never rule well without partaking of the ideas. Yet it would be the wiser course to follow up this thought more closely and (at those points where that admirable man abandons us to our own devices) to set it in the light through fresh endeavors, rather than to push it aside as worthless on the utterly paltry and pernicious pretext that the thing cannot be done. A constitution affording the greatest human freedom under laws so framed that the freedom of each can coexist with that of everyone else (not the greatest happiness, for that will ensue of its own accord anyway) is at the very least a necessary idea that must be laid at the foundation not only of the initial sketch of a political constitution but of every one of its laws, and in drawing which one must at the start leave out of account the present impediments, which perhaps arise not so much unavoidably from human nature as, rather, from having neglected the authentic ideas in the framing of law. For nothing more injurious, and nothing more unworthy of a philosopher, can be turned up than the mob-like appeal to a supposedly recalcitrant experience, which after all would have no existence whatever had those provisions been instituted in good time according to the ideas, and had crude concepts not—for the very reason that they were scooped up out of experience—thwarted, in their place, every good design. The more closely legislation and administration were fashioned in agreement with this idea, the scarcer punishments would surely grow, and it is then wholly rational (as Plato contends) to hold that under a flawless arrangement of them not a single such penalty would be called for. Now granted that this last may never be realized, the idea is nonetheless perfectly sound that erects this maximum as an archetype, so that by its measure the lawful constitution of humankind may be brought forever closer to the greatest attainable perfection. For what the supreme degree may be at which humankind must halt, and thus how wide the chasm that inevitably persists between the idea and its realization may turn out to be, is a thing that no one is able, or entitled, to fix—precisely because it is a matter of freedom, which can overstep whatever limit one might name.

But it is not only in the field where human reason exhibits a true causality—where ideas turn into operative causes (of deeds and of their objects), namely in the moral sphere—but with regard to nature itself as well that Plato justly discerns clear proofs of its origin from ideas. A growing plant, an animal, the orderly arrangement of the cosmic edifice (and so, presumably, the entire order of nature) make it plain that nothing but ideas could render them possible; that no single creature, taken under the particular conditions of its existence, does match the idea of the most perfect of its kind (any more than the human being matches the idea of humanity, which he even carries within his own soul as the archetype of his deeds); that those ideas are all the same, within the highest understanding, individual, immutable, through and through determinate, and the primordial causes of things, and that only the totality of their interconnection throughout the universe is fully adequate, wholly and solely, to that idea. If one strips away what is overdone in the phrasing, then the philosopher's flight of spirit—mounting up from the corporeal contemplation of the physical side of the world-order to its architectonic conjunction according to purposes, that is, according to ideas—represents an effort worthy of respect and of emulation; but as concerns whatever bears on the principles of morality, of legislation, and of religion, where the ideas are what first render experience itself (of the good) possible, though they can never be given full expression within it, there is a merit entirely its own, one that goes unacknowledged solely because it is appraised by those very empirical rules whose validity as principles was to have been cancelled by precisely those ideas. For where nature is in question, experience places the rule in our hands and is the wellspring of truth; where the moral laws are in question, however, experience is (alas!) the mother of mere semblance, and nothing is more culpable than to borrow the laws governing what I ought to do from, or to seek to hem them in by, that which is done.

In lieu of all these reflections, whose proper carrying-through is what in fact makes up the peculiar dignity of philosophy, we now occupy ourselves with a less resplendent, though not therefore meritless , labor—namely, that of rendering level and structurally sound the ground beneath those majestic moral edifices—ground riddled with all manner of molehills thrown up by a reason that tunnels fruitlessly, though in high hopes of treasure, and that leaves the edifice above unsafe. It is therefore the transcendental employment of pure reason, its principles and its ideas, that we are now obliged to become precisely acquainted with, if we are to gauge and appraise, as we should, the influence of pure reason and its worth. Yet before I lay this preliminary introduction aside, I entreat those who hold philosophy dear (which says more than one ordinarily encounters), should they find themselves persuaded by the present remarks and by what is to follow, to take the term idea into their keeping in accordance with its original meaning, lest it drift henceforth in among the remaining expressions by which every sort of representation is habitually labelled in heedless disorder, and lest the science suffer a loss thereby. We are, after all, in no want of designations aptly matched to each kind of representation, without our needing to trespass upon the domain of another. Here is a graduated ladder of them. The genus is representation as such (repraesentatio). Beneath it falls representation accompanied by consciousness (perceptio). A perception bearing solely on the subject, as a modification of its state, is sensation (sensatio); an objective perception is cognition (cognitio). This last is either intuition or concept (intuitus vel conceptus). The one bears directly upon its object and is singular; the other only mediately, by way of a mark that may be shared among several things. A concept, again, is either empirical or a pure concept, and a pure concept, to the extent that it takes its rise within the understanding alone (and not within any pure image belonging to sensibility), bears the name Notio. A concept assembled out of notions, one that outstrips the possibility of experience, is the idea, or concept of reason. To anyone who has once grown at home with this distinction, it is bound to prove insufferable to hear the representation of the color red termed an idea. It cannot even properly be styled a notion (a concept belonging to the understanding).

Section 2. On transcendental ideas

In the transcendental analytic we were shown, by way of illustration, how the merely logical form belonging to our cognition is able to harbor the source of pure a priori concepts—concepts that present objects in advance of any experience, or that rather flag the synthetic unity through which alone an empirical cognition of objects becomes possible at all. Once the form of judgments had been transformed into a concept of the synthesis of intuitions, it yielded up the categories, which govern every employment of the understanding within experience. By the same token, we have reason to anticipate that the form of the inferences of reason—applied to that synthetic unity of intuitions in conformity with the categories—will likewise harbor the source of distinctive a priori concepts; these we are entitled to name pure concepts of reason, or transcendental ideas, and it is they that will fix, in accordance with principles, the employment of the understanding across experience regarded in its entirety.

What reason accomplishes in drawing its inferences lay in rendering cognition universal by way of concepts, and a syllogism, taken on its own, is a judgment determined a priori across the full extent of its condition. Take the proposition, Cajus is mortal: this I might just as well draw straight from experience by means of the understanding alone. Yet what I am after is a concept holding within it the condition on which the predicate of this judgment (its assertion, generally speaking) rests (that is, in the present instance, the concept of the human being); and having subsumed under that condition, taken across its entire extent (all human beings are mortal), I then determine, on that basis, the cognition of my object (Cajus is mortal).

And so it is that, in the conclusion of a syllogism, we confine a predicate to some particular object, having earlier entertained it in the major premise across its whole extent and under a certain condition. Such a completed magnitude of extent, referred to a condition of this kind, we term universality (Universalitas). Its counterpart, over on the side of the synthesis of intuitions, is allness (Universitas), that is, the totality of conditions. Consequently, the transcendental concept of reason turns out to be none but the concept of the totality of conditions belonging to some given conditioned thing. Since it is the unconditioned that alone renders any totality of conditions possible, while conversely a totality of conditions is at every point already unconditioned in itself: it follows that a pure concept of reason as such admits of explication by means of the concept of the unconditioned, provided this concept carries within it a ground for synthesizing the conditioned.

However many sorts of relation there are that the understanding pictures to itself through the categories, that same number of pure concepts of reason will there prove to be as well; and so we shall have to look, first, for an unconditioned belonging to the categorical synthesis within a subject, secondly, to the hypothetical synthesis of the members making up a series, and thirdly, to the disjunctive synthesis of the parts within a system.

For there exist correspondingly many species of syllogism, each of them pressing on through prosyllogisms toward the unconditioned: one toward a subject that is itself no longer a predicate at all, a second toward a presupposition presupposing nothing beyond itself, and a third toward an aggregate of the members of a division such that nothing further is called for to bring the division of a concept to completion. This is why the pure concepts of reason bearing on totality in the synthesis of conditions are indispensable—if only as problems set for us, whereby the understanding's unity is to be prolonged, so far as may be, right up to the unconditioned—and why they take root in the very nature of human reason; granted, these transcendental concepts may for the rest want any use befitting them in concreto, so that their sole utility consists in steering the understanding in a direction wherein its own employment, stretched to the very limit, is at once brought into thoroughgoing accord with itself.

But in speaking here of a totality of conditions, and of the unconditioned, under a heading shared by every concept of reason, we run up once more against a term that we can ill spare and yet, on account of an ambiguity that long abuse has fastened onto it, cannot deploy with confidence. The word absolute ranks among the handful of terms that in their primordial sense came to fit a concept so precisely that no other word of the very same language afterward suits it exactly—and whose loss, or what comes to the same thing, whose unsteady use, must on that account drag along with it the forfeiting of the concept itself, a concept, moreover, that, since it exercises reason to no small degree, can hardly be given up without serious damage to every transcendental appraisal. Nowadays the word absolute frequently serves simply to signal that something obtains of a thing taken in itself and therefore internally. On that reading, absolutely possible would designate whatever is possible in its own right (interne)—which is, in point of fact, the least that can be affirmed of any object. Now and then, by contrast, it is put to work to signal that something holds good under every relation (without restriction)—absolute sovereignty, say—and on this reading absolutely possible would pick out whatever is possible in every intention, in every relation, and this, in turn, is the utmost I am in a position to assert regarding the possibility of any thing. Granted, these two senses do on occasion converge. Whatever is internally impossible, to take one case, will likewise be impossible under every relation and therefore impossible in the absolute sense. For the most part, though, they stand infinitely far apart, and there is no route by which I might infer that a thing's being possible in itself makes it, for that reason, possible under every relation and so possible absolutely. Regarding absolute necessity, indeed, I shall establish further on that it by no means depends in all cases upon inner necessity, and must accordingly not be treated as saying the same thing as the latter. Where a thing's opposite is internally impossible, that opposite is of course impossible under every intention as well, so that the thing is itself necessary absolutely; but the converse inference is barred to me—that whatever is necessary absolutely has an opposite that is internally impossible, that is, that the absolute necessity of things amounts to an inner necessity; for such inner necessity is, in certain instances, an utterly hollow phrase to which we can attach not the slightest concept, whereas the necessity of a thing under every relation (with respect to all that is possible) brings along with it determinations of a quite distinctive kind. And since a philosopher can never look with indifference upon the loss of a concept of broad application within speculative philosophy, my hope is that he will likewise not regard with indifference the fixing and the careful safekeeping of the term to which that concept clings.

It is in this enlarged sense, accordingly, that I shall avail myself of the word absolute, setting it over against what holds only comparatively or under some special consideration; for the latter stands restricted to conditions, whereas the former is valid with no restriction whatever.

The transcendental concept of reason, then, is invariably directed at nothing but the absolute totality in the synthesis of conditions, and it comes to rest nowhere save at the unconditioned in the strict sense—unconditioned, that is, under every relation. For pure reason hands everything over to the understanding, which in the first place bears upon the objects of intuition, or rather upon their synthesis within the imagination. To itself alone reason keeps back the absolute totality in the employment of the concepts of the understanding, striving to carry the synthetic unity that gets thought in the category all the way out to the strictly unconditioned. The former, accordingly, may be styled the unity of reason among appearances, much as the latter, the one that the category articulates, may be styled the unity of the understanding. And so reason bears upon the employment of the understanding and upon nothing else—yet not insofar as this employment holds the ground of a possible experience (an absolute totality of conditions being no concept of any use within experience, seeing that no experience is ever unconditioned), but rather so as to lay down for it a bearing toward a certain unity that lies beyond any concept the understanding possesses, a unity that comes down to drawing together all the acts of the understanding, in regard to each and every object, into one absolute whole. For this reason the objective employment of the pure concepts of reason remains at all times transcendent, while that of the pure concepts of the understanding, being what it is by nature, must at all times stay immanent, confined as it is to possible experience alone.

What I mean by an idea is a necessary concept of reason for which the senses can furnish no congruent object. The pure concepts of reason we have just been weighing are, therefore, transcendental ideas. They count as concepts of pure reason; for they view all cognition drawn from experience as determined by way of an absolute totality of conditions. Far from being fabricated at will, they are laid upon us as a charge by the very nature of reason, and for that reason bear of necessity upon the whole employment of the understanding. They are, in the last place, transcendent, overshooting the bounds of all experience, within which, then, no object can ever turn up that would be adequate to the transcendental idea. To call something an idea is to claim, as measured by the object (as of an object of the pure understanding), a great deal, yet, as measured by the subject (in regard, that is, to its actuality under an empirical condition), on precisely that ground very little, since a maximum, of which it is the concept, can never be delivered congruently in concreto. And since it is this latter that, in the merely speculative employment of reason, really constitutes the entire aim—and since drawing near to a concept never in fact attained in the exercise counts for just as much as missing that concept altogether—one says of a concept of this sort: it is nothing but an idea. One might put it thus: the absolute whole of all appearances is nothing but an idea, for since we are never able to sketch its like in an image, it stays a problem admitting of no solution at all. By contrast, since in the practical employment of the understanding everything turns solely upon the carrying of rules into practice, the idea of practical reason can at all times be genuinely delivered, if only in part, in concreto—indeed, it is the condition, not to be dispensed with, of every practical employment of reason. The exercise of it is at every point bounded and deficient, yet the bounds themselves elude determination, so that it always stands under the sway of the concept of a completeness that is absolute. The practical idea, on this showing, is at every point supremely fruitful and, where actual actions are concerned, necessary past all avoidance. Within it pure reason possesses even a causality for actually bringing forth what its concept holds; and so of wisdom one may not, in a manner of speaking, say slightingly that it is nothing but an idea—rather, on the very ground that it is the idea of the necessary unity of all possible ends, it has to serve as the rule for everything practical, as an original condition, or at the least a limiting one.

However true it may be that of the transcendental concepts of reason we are bound to say they are nothing but ideas, we are in no way therefore to look upon them as idle and void. For even granting that no object gets determined through them, they can still, deep down and without being noticed, serve the understanding as a canon for the extended and concordant employment of itself—whereby it comes to cognize, true enough, no object over and above what its concepts would already let it cognize, and yet finds itself, within that very cognition, guided further and better . To say nothing of how they may perhaps open up a passage leading from the concepts of nature over to the practical ones, and in just this way secure for the moral ideas themselves a footing, together with a linkage to reason's speculative cognitions. Clarification on all of this we must look for as the inquiry proceeds.

As our purpose requires, however, we here lay the practical ideas to one side and so take reason up only in its speculative bearing, and, narrower still within that, only in its transcendental employment. The very road we struck out on earlier, in deducing the categories, we must now strike out on again: namely, to weigh up the logical form of rational cognition and to find out whether reason might not, by that route, itself become a wellspring of concepts under which objects, taken in themselves, come to be regarded as determined synthetically a priori in respect of one function of reason or another.

Reason, viewed as the capacity answering to a certain logical form of cognition, is the capacity for drawing inferences—that is, for judging in a mediated fashion (by subsuming the condition of some possible judgment beneath the condition of a judgment already given). This given judgment supplies the universal rule (the premise stated first, major). Placing the condition of some further possible judgment beneath the condition of the rule yields the premise stated below (minor). The actual judgment, which pronounces the rule's assertion in the subsumed case, is the closing proposition (conclusio). For the rule asserts something in a universal way under a certain condition. Now, in a case that comes up, the rule's condition is met. And so whatever held universally under that condition is taken to hold in the case that comes up as well (the case carrying this condition along with it). It is readily seen that reason reaches a cognition by way of acts of the understanding which together make up a series of conditions. Suppose I reach the proposition all bodies are alterable solely by setting out from the more distant cognition (one in which the concept of body has yet to appear, though it does hold the condition of that concept): everything composite is alterable; then move on from this to a nearer cognition, standing under the condition of the first: bodies are composite; and from this, only then, on to a third, which at last ties the distant cognition (alterable) to the one now before me: bodies, consequently, are alterable: in that case I have made my way, through a series of conditions (premises), to a cognition (conclusion). Now any series whatever whose exponent (that of the categorical or hypothetical judgment) is given admits of being carried on; and thus the selfsame act of reason issues in the ratiocinatio polysyllogistica, which is a chain of inferences extendable into indeterminate reaches either on the side of the conditions (per prosyllogismos) or on that of the conditioned (per episyllogismos).

One soon comes to notice, however, that the chain, or series, of prosyllogisms—that is, of cognitions inferred over on the side of the grounds or the conditions for a given cognition, or, to phrase it otherwise, the ascending series of syllogisms—must after all stand in another relation to the faculty of reason than does the descending series, i.e. reason's advance over on the side of the conditioned by way of episyllogisms. For seeing that, in the first case, the cognition (conclusio) is given merely as conditioned, one can arrive at it by means of reason in no other way than on the assumption, at the very least, that all the members of the series on the side of the conditions are given (a totality in the series of premises)—only on that assumption being the judgment at hand possible a priori; whereas on the side of the conditioned, or of the consequences, what gets thought is a series merely coming to be, not one already presupposed in full or given, and hence no more than a progression held in potential. For this reason, once a cognition is looked upon as conditioned, reason finds itself constrained to look upon the series of conditions along the ascending line as brought to completion and as given in respect of its totality. But if this very cognition is at the same time looked upon as the condition of other cognitions, which among themselves compose a series of consequences along the descending line, then it may be all one to reason how far this advance reaches out a parte posteriori, and whether a totality of the series is so much as possible anywhere; for reason has no need of such a series in reaching the conclusion set before it, that conclusion being already, through its grounds, sufficiently determined and secured a parte priori. It may well be that, on the side of the conditions, the series of premises does possess a first as its supreme condition, or that it does not and so runs on a parte priori without any limit; even so, it has to comprise a totality of the condition, granting that we could never manage to lay hold of it; and the whole series has to be true without condition if that conditioned thing which is viewed as a consequence springing from it is to pass for true. This is a demand made by reason, which proclaims its cognition to be determined a priori and to be necessary: whether in its own right, in which case no grounds are wanted, or, should it be derived, then as one link within a chain of grounds that is itself true in an unconditioned manner.

Section 3. System of transcendental ideas

What occupies us here is not a logical dialectic, one that abstracts from all content of cognition and merely lays bare the false semblance in the form of the inferences of reason, but a transcendental one, which is meant to contain, wholly a priori, the origin of certain cognitions springing from pure reason together with inferred concepts whose object can never be given empirically at all, and which for that reason lie entirely outside the capacity of the pure understanding. We have inferred, from the relation that the transcendental employment of our cognition must naturally bear to its logical employment—in judgments no less than in inferences—that dialectical inferences can be of only three kinds, answering to the three ways of inferring by which reason is able to reach cognitions from principles, and that in every case their task consists in climbing up from that conditioned synthesis, to which the understanding stays perpetually tied, toward an unconditioned one that it can never attain.

Now, the universal element in every relation that our representations are capable of having is this: 1) their relation to the subject, 2) their relation to objects, and here either as appearances or as objects of thinking in general. If this subdivision is combined with the one given above, then every relation of the representations—of which we are able to frame either a concept or an idea—turns out to be threefold: 1. its relation to the subject, 2. to the object's manifold in appearance, 3. to all things whatsoever.

Now, pure concepts as such all have to do with the synthetic unity of representations, whereas concepts of pure reason (transcendental ideas) are directed at the unconditioned synthetic unity embracing all conditions whatsoever. It follows that every transcendental idea can be assigned to one of three classes: the first takes in the thinking subject's absolute (unconditioned) unity; the second, the absolute unity belonging to the series of the conditions of appearance; the third, the absolute unity proper to the condition of all objects of thinking in general.

The thinking subject forms the object of psychology; the sum of all appearances (the world), that of cosmology; and that thing which holds the highest condition for the possibility of all that admits of being thought (the being of all beings), that of theology. In this way pure reason hands over the idea of a transcendental doctrine of the soul (psychologia rationalis), of a transcendental science of the world (cosmologia rationalis), and lastly of a transcendental cognition of God (theologia transscendentalis). Even the mere sketch of the one or the other of these sciences in no way stems from the understanding, even were it bound up with reason's highest logical use, i.e., with every conceivable inference, so as to move from one object of the understanding (an appearance) to all the rest, right down to the remotest members of the empirical synthesis; rather, it is merely a pure and genuine product or problem of pure reason.

Which modi of the pure concepts of reason stand under these three headings of all transcendental ideas will be set forth in full in the chapter that follows. They proceed along the guiding thread of the categories. For pure reason never relates directly to objects, but rather to the understanding's concepts of them. In the same way, only the complete working-out can show how reason, simply by the synthetic use of that very function which serves it in the categorical syllogism, is bound to come upon the concept of the thinking subject's absolute unity; how, in the hypothetical case, its logical procedure yields the idea of what is unconditioned outright in a series of given conditions; and how, lastly, the bare form of the disjunctive syllogism cannot but drag along with it the supreme rational concept of a being of all beings—a notion that strikes one, at first sight, as utterly paradoxical.

Of these transcendental ideas no objective deduction is, strictly speaking, possible, of the kind we were able to supply for the categories. For in truth they stand in no relation to any object that might be given as congruent with them, and this precisely because they are nothing but ideas. A subjective derivation of them from the nature of our reason, however, we could indeed undertake; and that has in fact been carried out in the present chapter.

One readily sees that pure reason aims at nothing other than the absolute totality of the synthesis on the side of the conditions (whether of inherence, of dependence, or of concurrence), and that it has no business with the absolute completeness on the side of the conditioned. For reason requires the former alone, so as to lay down in advance the entire series of conditions and thus supply them to the understanding a priori. Yet the moment a completely (and unconditionally) given condition is present, no concept of reason is any longer called for as regards the continuation of the series; for on its own the understanding accomplishes every step downward from the condition to the conditioned. Accordingly, the transcendental ideas are of service solely for the ascent through the series of conditions up to the unconditioned, that is, to the principles. As regards the descent to the conditioned, by contrast, our reason does make a far-reaching logical use of the laws of the understanding, yet no transcendental use whatever; and should we frame an idea of the absolute totality of such a synthesis (the progressus)—say, of the entire sequence of all future changes in the world—this is a thought-thing (ens rationis), one thought up merely at will and not necessarily presupposed by reason. For while the totality of a thing's conditions is presupposed for the possibility of the conditioned, the totality of its consequences is not. Such a concept, therefore, is no transcendental idea—and it is transcendental ideas alone that occupy us here.

Finally, one also comes to notice that a certain coherence and unity shines out among the transcendental ideas themselves, and that by means of them pure reason arranges the whole of its cognitions into a system. To advance from cognition of oneself (the soul) to cognition of the world, and by its means to the primordial being, is a progression so natural that it looks like the logical passage of reason from premises to conclusion ³⁶. Now whether a kinship of the same sort as that between the logical and the transcendental procedure really does lie secretly at the ground here is likewise one of those questions whose answer one may expect only as these investigations are pursued further. For the moment we have already gained our end, in that we have managed to lift the transcendental concepts of reason—which are otherwise wont to mingle, in the theorizing of the philosophers, among other concepts, without these philosophers even properly telling them apart from concepts of the understanding—out of this equivocal position, to specify their origin and, at one stroke, their determinate number, past which none can ever be added, and to exhibit them within a systematic coherence, whereby a special field is marked off and bounded for pure reason.

Second Book. On the Dialectical Inferences of Pure Reason

One may say that a merely transcendental idea has for its object something for which one possesses no concept, even though this idea is produced quite necessarily within reason in accordance with its original laws. For, in truth, an object that is supposed to correspond to reason's requirement likewise admits of no concept of the understanding — that is, of a concept that can be displayed and rendered intuitable within a possible experience. One would, however, express the matter better, and with less risk of being misunderstood, were one to say: that of the object which corresponds to an idea we can have no acquaintance, although we can indeed have a problematic concept of it.

Now the transcendental (subjective) reality of the pure concepts of reason rests at least upon the fact that a necessary inference of reason brings us to such ideas. There will accordingly be inferences of reason that contain no empirical premises and by means of which, from something we know, we draw a conclusion to something else of which we have no concept, yet to which, through an inevitable illusion, we grant objective reality. With respect to their outcome, such inferences are therefore to be termed ratiocinating rather than inferences of reason: although, on account of what occasions them, they may indeed carry the latter title, since they are neither invented nor arisen by chance but issue from the very nature of reason itself. They are sophistications that belong not to human beings but to pure reason itself, from which not even the wisest of all human beings can free himself, and though after much labor he may perhaps guard against the error, the illusion that unceasingly pinches and mocks him he can never entirely shake off.

Of these dialectical inferences of reason, then, there are only three sorts, precisely as many kinds as there are ideas onto which their concluding propositions issue. In the inference of reason of the first class I conclude, from the transcendental concept of the subject, which contains nothing manifold, to the absolute unity of this subject itself, of which in this way I have utterly no concept. This dialectical inference I shall call the transcendental paralogism. The second class of ratiocinating inferences is laid out upon the transcendental concept of the series of conditions, in its absolute totality, for a given appearance as such; and from this — that on the one side I invariably possess a self-contradictory concept of the series' unconditioned synthetic unity — I conclude to the correctness of the opposing unity, of which I nonetheless likewise have no concept. The state of reason in these dialectical inferences I shall call the antinomy of pure reason. Finally, in accordance with the third kind of ratiocinating inference, I conclude, from the totality of the conditions for thinking objects as such, so far as they may be given to me, to the absolute synthetic unity of all conditions of the possibility of things as such — that is, from things that I do not know through their mere transcendental concept, to a being of all beings, which I know even less through a transcendental concept, and of whose unconditioned necessity I am unable to form any concept. This dialectical inference of reason I shall call the ideal of pure reason.

Chapter 1. On the Paralogisms of Pure Reason

A logical paralogism has its falsity in the mere form of a rational syllogism, let its content be whatever it may. A transcendental paralogism, by contrast, rests on a transcendental ground that makes one draw a formally invalid conclusion. A fallacy of this sort, accordingly, is rooted in the very nature of human reason and brings with it an illusion that, while unavoidable, is not beyond resolution.

We arrive now at a concept that our earlier general roster of transcendental concepts did not list, though it nonetheless has to be reckoned among them—and this without in any way modifying that table or pronouncing it incomplete. It is the concept—or, should one rather have it so, the judgment—I think. Yet it is easy to see that this is the vehicle carrying all concepts whatever, the transcendental ones included, so that it is invariably co-thought along with them and is thus itself no less transcendental, though it merits no title of its own, since its whole office is to exhibit every act of thinking as something belonging to consciousness. Nevertheless, however free of the empirical (the imprint of the senses) it may be, it does help us mark off two sorts of object grounded in the very nature of our representational power. I, taken as thinking, count as an object of inner sense, and the name for this is soul. Whatever, on the other hand, stands as an object of the outer senses bears the name body. The phrase 'I, as a thinking being', therefore, already picks out the subject matter of that psychology which one may term the rational doctrine of the soul, on the assumption that I ask to know nothing of the soul beyond what may be concluded—apart from all experience (which fixes me more determinately and in concreto)—from the concept I so far as this turns up throughout all thinking.

Now the rational doctrine of the soul really is a venture of just this sort; for were even the slightest empirical element of my thinking—some specific perception of my own inner condition—admitted among this science's sources of cognition, it would thereby cease to be rational and turn into an empirical doctrine of the soul. So we already have before us a would-be science resting on the one proposition I think, and its soundness or unsoundness is something we may here examine quite appropriately, as befits the character of a transcendental philosophy. It should give no one pause that in this proposition, which voices the perception of oneself, I do in fact possess an inner experience, so that the rational doctrine of the soul built upon it can never be pure but rests partly on an empirical principle. For this inner perception amounts to nothing beyond the bare apperception I think—the very thing that first makes possible all the transcendental concepts, wherein one says: I think substance, cause, and so on. For inner experience as such together with its possibility—or, equally, perception as such together with its bearing on other perception, where no particular difference or determination among perceptions is empirically supplied—may not pass as empirical cognition; it has instead to be treated as cognition of the empirical taken generally, and it falls under the inquiry into how any experience whatever is possible, an inquiry that is of course transcendental. The tiniest object of perception (say, mere pleasure or displeasure) annexed to the general representation of self-consciousness would straightaway convert rational psychology into an empirical psychology.

I think, then, is the one and only text of rational psychology, and out of it the whole of that science's wisdom is meant to be unfolded. It is readily apparent that this thought, once it is made to bear on an object (my own self), admits of nothing but transcendental predicates of that object: for the faintest empirical predicate would ruin the science's rational purity and its freedom from all experience.

Here, though, our sole task will be to keep to the guiding thread of the categories; only, because in this instance a thing—namely I, as a thinking being—is what is first given, we shall leave the earlier ordering of the categories among themselves (as their table lays it out) untouched, yet start at this point from the category of substance, by which a thing in itself is represented, and then work our way back down their sequence. Hence the topic of the rational doctrine of the soul, the source from which all its remaining content has to be drawn, runs as follows:³⁷

Out of these elements every concept belonging to the pure doctrine of the soul springs solely by way of combination, without so much as acknowledging any further principle. Considered simply as an object of inner sense, this substance furnishes the concept of immateriality; as a simple substance, that of incorruptibility; through its identity, as an intellectual substance, it furnishes personality; and the three together furnish spirituality; its relation to objects in space furnishes commercium with bodies; the thinking substance is thereby represented as the principle of life within matter, that is, as soul (anima) and as the basis of animality, and this last, once curbed by spirituality, gives immortality.

It is upon this that there rest four paralogisms of a transcendental doctrine of the soul, a doctrine mistakenly regarded as a science of pure reason treating of what our thinking being is by nature. Yet at their basis we are able to place nothing beyond the plain representation I—wholly devoid of content in its own right, and such that one cannot even call it a concept, but only a bare consciousness attending every concept. By means of this I, or He, or It (the thing) that carries out the thinking, all that gets represented is a transcendental subject of the thoughts, = X; it is known only through those thoughts, which serve as its predicates, and taken by itself we can form of it not the slightest concept, so that we keep circling it perpetually, obliged as we are to draw on its representation before we can pass any judgment about it at all—an awkwardness inseparable from the case, since consciousness in itself is less a representation singling out some particular object than a form belonging to representation generally, so far as representation deserves the name of cognition; and it is of the latter alone that I can say I thereby think anything whatever.

Still, it must appear odd right from the start that the condition on which I think at all—which is accordingly no more than a feature of my own subject—should hold good at the same time for whatever thinks, and that on the basis of a seemingly empirical proposition we should venture to rest an apodictic and universal judgment, to wit: that everything which thinks is so constituted as the deliverance of self-consciousness pronounces it to be in my own case. The reason for this, however, is that to things we are bound of necessity to attribute a priori every property making up the conditions apart from which we cannot think them at all. Now no outer experience, but self-consciousness alone, can give me even the barest representation of a thinking being. Objects of that kind, therefore, come to no more than the carrying-over of this consciousness of mine onto other things, which are pictured as thinking beings by that transfer alone. The proposition 'I think' is, however, entertained here in merely problematic fashion—not as it might carry a perception of some existence (the Cartesian cogito, ergo sum), but purely in point of its possibility, so as to discover what properties might issue, from a proposition thus utterly simple, for the subject of it (whether or not any such subject actually exists).

Were anything more than the cogito to underlie our pure rational cognition of thinking beings as such; were we to enlist as well the observations on how our thoughts interplay and the natural laws of the thinking self derivable from them: what would emerge is an empirical psychology, a sort of physiology of inner sense, able perhaps to account for that sense's appearances, but never fit to bring to light properties lying wholly beyond possible experience (such as that of the simple), nor to teach anything apodictically about the nature of thinking beings in general; it would thus fall short of being a rational psychology.

Since the proposition I think (entertained problematically) carries within it the form of every judgment of the understanding whatever and rides along with all the categories as their vehicle: it becomes plain that whatever is inferred from it can involve only a transcendental employment of the understanding, one that refuses any admixture of experience, and about whose upshot—given what we established earlier—we can already form no favorable notion beforehand. Let us, then, track it with a critical eye across all the predicaments of the pure doctrine of the soul, yet, to be brief, allow the scrutiny of them to run on as a single unbroken sequence.

To begin with, one general observation may sharpen our vigilance toward this style of inference. I cognize no object simply in virtue of thinking; a given intuition must first be determined by me relative to that unity of consciousness in which all thinking has its being—only then can I cognize any object at all. Accordingly, my being aware of myself as thinking does not amount to my cognizing myself; that happens only when I am aware of the intuition of myself as determined in respect of the function of thought. For this reason all the modi of self-awareness in thinking are as yet no concepts of the understanding regarding objects (categories); they are mere logical functions, handing thought no object whatever to be cognized, and consequently handing me my own self no more than the rest as an object. What counts as the object is not the awareness of the determining self but solely that of the determinable self—that is, of my inner intuition (to the degree that its manifold admits of being conjoined according to the general condition governing the unity of apperception in thought).

1) Throughout every judgment I am, invariably, the determining subject of the relation that makes the judgment up. But that I who think must always, in thinking, hold as subject, as something not to be viewed as merely clinging to thought after the manner of a predicate, is a proposition apodictic and indeed identical; it does not, however, imply that I, qua object, am a being that subsists on its own or a substance. This latter claim reaches very far and hence calls for data nowhere to be found in thinking—perhaps (so far as I regard the thinking merely as such) more than I shall ever come across anywhere within it.

2) That the I of apperception is, in consequence, in each act of thinking a singular incapable of being resolved into a multitude of subjects, and hence marks out a logically simple subject—this already resides in the concept of thinking and is thus an analytic proposition; but it does not carry the meaning that the thinking I is a simple substance, which would make it a synthetic proposition. The concept of substance is invariably tied to intuitions, and these, in my case, can be nothing but sensible, lying therefore altogether beyond the field of the understanding and its thinking—though thinking is precisely what is at issue here when it is claimed that the I is simple in thought. It would, moreover, be astonishing if what ordinarily demands so much apparatus—in order to make out, within what intuition sets before us, which element in it is substance, and, harder still, whether that substance can also be simple (as with the parts of matter)—were here handed to me outright, as though by revelation, in the barest representation there is.

3) The proposition asserting my own identity amid all the manifold of which I am conscious is one that likewise lies within the very concepts, and so is analytic; but this identity of the subject, of which I can grow conscious across all its representations, has no bearing on the intuition of that subject whereby it is given as object, and it cannot therefore stand for the identity of the person—by which is meant the awareness that one's own substance, as a thinking being, stays identical through every alteration of its states—an identity whose proof the mere analysis of 'I think' could never furnish, calling instead for sundry synthetic judgments that rest upon the intuition given.

4) 'I set my own existence, as that of a thinking being, apart from other things beyond me (my body among them)'—this too is analytic; for by other things I mean just those I conceive as set apart from myself. But whether this awareness of myself could so much as occur in the absence of things beyond me by which representations reach me—whether, that is, I might exist as a merely thinking being (without being a human)—of this the proposition tells me nothing at all.

So it turns out that dissecting the awareness of myself in thinking as such yields not the least gain as regards cognizing myself qua object. The logical elucidation of thought in general gets mistaken for a metaphysical determination of the object.

One great stumbling block—indeed the single one—confronting our whole critique would appear were it feasible to establish a priori that every thinking being is in itself a simple substance, and, as such (a corollary of the very same proof-ground), bears personality inseparably about it and is aware of an existence divorced from all matter. For in that event we should after all have set foot past the sensible world, entering the domain of noumena, whereupon let none dispute our title to range further within it, to till it, and—according as each man's fortunate star smiles on him—to stake out holdings there. For the proposition 'Any thinking being as such is a simple substance' is synthetic a priori, because, first, it oversteps the concept placed at its base and appends the mode of existence to thinking as such, and, second, it fastens onto that concept a predicate (simplicity) incapable of being given in any experience. Synthetic propositions a priori, then, would prove workable and permissible not merely, as we maintained, with respect to objects of possible experience and specifically as principles for the very possibility of such experience, but might reach out to things generally and in themselves as well—an inference that would spell the close of this entire critique and enjoin us to leave matters as they stood. Yet the peril here proves less grave once one draws nearer to the matter.

Governing the procedure of rational psychology there is a paralogism, exhibited in the following rational syllogism.

Whatever admits of being thought only as subject likewise exists only as subject and is on that account substance.

Now a thinking being, viewed purely as such, admits of being thought only as subject.

Hence it too exists only as such—that is, as substance.

In the major premise the being spoken of is one thinkable at large, in every regard, and so also as it might be furnished in intuition. In the minor premise, by contrast, the being figures only so far as it regards itself as subject in bare relation to thinking and the unity of consciousness, and not concurrently in relation to the intuition by which it would be handed to thought as object. Thus it is per sophisma figurae dictionis—by a deceptive inference, that is—that the conclusion gets drawn.³⁸

That this diagnosis of the celebrated argument as a paralogism hits the mark exactly comes out clearly if one cares to look back here at the general remark on the systematic exhibition of the principles, and at the section dealing with the noumena, where it was shown: that the concept of a thing capable of existing on its own as subject but not as mere predicate still brings with it no objective reality whatever—that one cannot tell, in other words, whether any object could ever answer to it, since the possibility of such a manner of existing is not grasped, so that the concept delivers no cognition at all. If, then, it is under the title of a substance to point to an object that can be given—if it is to become a cognition—then some abiding intuition, being the condition one cannot dispense with for a concept's objective reality (namely the very means by which the object is given), has to be set beneath it. But in inner intuition we possess nothing abiding at all, since the I is merely my consciousness that I think; and so, if we halt at thinking alone, we are short of the condition required for bringing the concept of substance—of a subject that persists on its own, that is—to bear on oneself as a thinking being; whereupon the simplicity of substance tied to that concept collapses together with the concept's objective reality, converting into a bare logical and qualitative oneness of self-consciousness in thought as such, the subject being composite or not, no matter which.

Refutation of Mendelssohn's Proof of the Soul's Abidingness.

This penetrating philosopher was quick to detect, in the customary argument meant to show that the soul (granting it to be a simple being) cannot pass out of existence through partition, a shortfall in meeting the aim of guaranteeing it the requisite endurance, seeing that one might yet suppose its existence to lapse by fading away. In his Phädon he set out to keep this perishing—which would be genuine annihilation—away from the soul, presuming to demonstrate: that a simple being can in no way cease to exist, for, being incapable of diminution and hence of forfeiting bit by bit some portion of its existence and so of gradually passing into nothingness (having no parts, and thus no plurality, within it), it would leave no interval of time whatever between an instant in which it is and a further instant in which it is no more—which is impossible. — But he failed to reflect that, even were we to concede the soul this simple nature—that it holds, namely, no manifold lying side by side, and so no extensive magnitude—one can no more refuse it than any existing thing an intensive magnitude, a degree of reality, that is, in respect of all its powers, indeed of everything at all that constitutes existence, a degree that may fall away through endlessly many ever-slighter degrees, so that the supposed substance (the thing whose abidingness is not already settled on other grounds) could be turned to nothing, not indeed by partition, yet by a stepwise slackening (remissio) of its forces (through languescence, then, if I may help myself to the term). For consciousness itself possesses at all times a degree open to still further reduction³⁹, and hence so does the power of being conscious of oneself, and so do all the other powers. — The abidingness of the soul, viewed as a bare object of inner sense, thus stays undemonstrated and even indemonstrable, though its abidingness throughout life—since the thinking being (as a human) is at once an object of the outer senses to itself—is evident on its own; but with this the rational psychologist is in no way content, bent as he is on proving, out of mere concepts, the soul's absolute abidingness reaching even past life⁴⁰.

Suppose now we take the propositions above—as, taken they must be, holding for every thinking being within rational psychology considered as a system—in synthetic interconnection, and set out from the category of relation with the proposition that all thinking beings are, as such, substances, running back down their series until the circle comes round: we light in the end on the existence of these beings, an existence of which, within this system and in independence of external things, they are not only conscious but which they can, moreover (as regards the abidingness that necessarily belongs to the character of substance), settle out of their own resources. From this, however, it emerges that idealism—the problematic kind, at any rate—cannot be escaped within that very rationalist system, and that, if the existence of outer things is in no way needed for settling one's own existence in time, those outer things are assumed to no purpose whatever, past all power of ever proving them.

If instead we pursue the analytic route—where the 'I think', as a proposition already enclosing an existence within itself, is taken as given, so that modality forms the base—and take it apart to learn its content, namely whether and how this I settles its existence in space or time by that alone, then the propositions of the rational doctrine of the soul would set out not from the concept of a thinking being at large but from an actuality, and from the way in which this actuality is conceived—once all that is empirical about it has been detached—there would be inferred what belongs to a thinking being in general, as the table below displays.

Since the second proposition leaves it open whether I can exist and be conceived solely as subject and not likewise as another's predicate, the concept of a subject is being employed here in a merely logical way, and it stays undecided whether substance is to be meant by it or not. In the third proposition, by contrast, the absolute unity of apperception—the simple I within that representation to which every combining or separating that constitutes thought is referred—acquires weight in its own right, even while I have thus far fixed nothing touching the subject's makeup or subsistence. Apperception is a real something, and its simplicity is already contained in its very possibility. In space, meanwhile, nothing real is simple; for points (space's sole simple items) are nothing but boundaries, not themselves anything apt to constitute space as a part of it. What follows from this is the impossibility of accounting for my makeup, as a merely thinking subject, on the grounds of materialism. But since my existence is treated as given in the first proposition—which does not run 'every thinking being exists' (a claim that would assert absolute necessity and hence say far too much of them), but only 'I exist thinking'—the proposition is empirical and holds the determinability of my existence solely as concerns my representations in time. Since here again I stand in need, first of all, of something abiding, of which nothing whatever is given me in inner intuition so long as I merely think myself: the mode in which I exist—as substance or as accident—simply cannot be settled by this bare self-consciousness. And so, if materialism will not serve to explain my existence, spiritualism proves every bit as inadequate to it; the upshot being that by no means at all, whatever it might be, can we know a thing about our soul's makeup where the possibility of its detached existence is concerned.

And how, in any case, should it be possible—by way of the unity of consciousness, which we ourselves are acquainted with only because we cannot do without it for the possibility of experience—to pass beyond experience (our existence in life) and even to broaden our cognition to the nature of thinking beings generally through the proposition 'I think', empirical yet left undetermined as regards every kind of intuition?

There exists, then, no rational psychology as a doctrine capable of yielding us any supplement to our self-knowledge, but only one as a discipline—setting for speculative reason in this field boundaries not to be crossed, on one side that we may not cast ourselves into the embrace of a soulless materialism, on the other that we may not stray off, adrift, into a spiritualism baseless for us amid life; it prompts us rather to look on this refusal of our reason to answer satisfyingly the inquisitive questions that overreach the present life as a signal from reason itself, bidding us redirect our self-knowledge from barren, exorbitant speculation to a fruitful practical use—a use which, even while forever aimed only at objects of experience, nonetheless fetches its principles from higher and shapes our conduct as though our vocation stretched infinitely past experience, and thus past this present life.

From all of this it becomes visible that rational psychology owes its origin to nothing but a misunderstanding. The unity of consciousness underlying the categories is here mistaken for an intuition of the subject as object, and to it the category of substance is then applied. Yet it is no more than the unity within thinking, by which on its own no object is given, so that the category of substance—presupposing, as it forever does, a given intuition—finds no application to it, leaving this subject wholly uncognized. By thinking the categories, therefore, the subject of the categories cannot arrive at a concept of itself as an object falling under them; for to think them it has to place beneath them its own pure self-consciousness—the very thing that was to have been explained. By the same token, that subject wherein the representation of time takes its original rise is unable, by that means, to fix its own existence in time; and where the fixing of existence in time is barred, so too is that other fixing—of the subject itself (as a thinking being in general) by means of categories.⁴¹

And so a cognition ventured past the confines of possible experience, one belonging nevertheless to humanity's supreme interest, evaporates—so far as it is to be credited to speculative philosophy—into thwarted hope; wherein all the same the severity of the critique, by demonstrating at once that it is impossible to fix anything dogmatically about an object of experience past experience's boundary, renders reason, amid this interest of its own, a service far from trifling: it makes reason equally secure against every conceivable claim to the contrary; and this can come about in no other way than by one's either proving one's proposition apodictically or, failing that, hunting down the roots of the failure, which, should they lie within the necessary confines of our reason, must then bind every antagonist under that identical law of forgoing all pretension to dogmatic assertion.

Even so, none of this costs us in the slightest the warrant—indeed the necessity—of positing a life to come, on the principles of that practical use of reason which is joined to the speculative; for on ordinary human reason the merely speculative proof could in any case never have exerted the least influence. It is poised on so fine a needle-point that even the Schools can hold it there only so long as they keep it forever spinning round that point like a top, so that in their own view it affords no lasting groundwork on which anything might be raised. The proofs of use to the world all keep here their full, unlessened worth, and gain rather in lucidity and artless conviction once those dogmatic presumptions are cleared away, for they lodge reason within its proper province—the order of ends, which is withal an order of nature too—a province that then, as a practical faculty in itself unfettered by the conditions of the latter, is warranted to enlarge the former, and with it our own existence, past the limits of experience and of life. Reasoning by the analogy with the nature of the living beings in this world—in whom reason has necessarily to adopt as a principle that not one organ, faculty, or drive is to be met with that is dispensable, or out of proportion to its use, and thus purposeless, but that each is exactly fitted to its vocation in life—the human being, who alone can after all harbor within himself the final end of it all, would have to be the sole creature left out of the rule. For his natural endowments—not merely with respect to the talents and drives for putting them to work, but chiefly the moral law within him—run out so far past every use and gain he could wring from them in this life that this law schools him to value above everything else the mere consciousness of an upright disposition, even where every advantage fails, even down to the ghostly show of fame after death, and he feels an inward calling to render himself, through his bearing in this world and by forgoing many advantages, fit for citizenship in a better one that he holds in idea. This forceful proof-ground, never to be overthrown, attended by an ever-swelling cognition of the purposiveness in all that lies before our eyes, by a vista onto the boundlessness of creation, and hence too by the awareness of a certain limitlessness in the possible growth of our knowledge together with a drive matched to it, remains standing yet, even should we have to renounce discerning the necessary endurance of our existence from the merely theoretical cognition of ourselves.

Conclusion of the Resolution of the Psychological Paralogism.

What produces the dialectical semblance in rational psychology is the mix-up of an idea belonging to reason (that of a pure intelligence) with the utterly indeterminate concept, in every respect, of a thinking being as such. I think my own self on behalf of a possible experience, while abstracting still from all actual experience, and I draw from this the conclusion that I could grow conscious of my existence even outside experience and its empirical conditions. Thus I mistake the feasible abstracting from my empirically determined existence for a supposed awareness of an existence my thinking self might have in separation, and I take myself to cognize the substantial in me as the transcendental subject, when all I hold in thought is the unity of consciousness that underlies every act of determining, this being the mere form of cognition.

The problem of explaining the soul's community with the body does not, strictly, fall to the psychology under discussion here, since its purpose is to prove the soul's personality even apart from that community (after death), making it, in the strict sense, transcendent, notwithstanding that it busies itself with an object of experience—but only so far as that object stops being one of experience. That said, our doctrine allows an adequate reply to be given to this question as well. The difficulty prompting the problem consists, as everyone knows, in the assumed unlikeness between the object of inner sense (the soul) and the objects of the outer senses, since to the former only time attaches, to the latter space as well, as the formal condition of their intuition. But bear in mind that the two kinds of object are marked off from one another in this respect not inwardly, but only so far as the one shows itself outwardly to the other, so that whatever grounds the appearance of matter as a thing in itself might well be not so unlike after all—and with that the difficulty melts away, leaving none but this: how a community of substances is at all possible, a question whose solution lies quite beyond the field of psychology and, as the reader will easily gather from what the Analytic said of basic forces and faculties, past all doubt beyond the field of every human cognition too.

General remark concerning the transition from rational psychology to cosmology.

That I think, or: that I exist in thinking, is an empirical proposition. But at the basis of any such proposition lies empirical intuition, and consequently also the object thought of as appearance, so that it seems as though, on our theory, the soul were wholly and entirely, even in its thinking, transformed into appearance, and in this way our consciousness itself, as a mere semblance, would in fact have to come to nothing.

Thinking, considered on its own, is nothing but the logical function, and thus pure spontaneity in the connecting of the manifold belonging to a merely possible intuition; and it presents the subject of consciousness in no way as appearance, for this one reason: that it pays no regard at all to how the intuition is given, whether sensibly or intellectually. By this I represent myself, to myself, neither as I actually am nor as I appear to my own view, but I think of myself simply as any object as such, abstracting from the kind of intuition through which it is given. If I here represent myself as the subject of thoughts, or likewise as the ground of thinking, these ways of representing do not stand for the categories of substance or of cause, since the latter are precisely those functions of thought (of judgment) as already applied to our sensible intuition—an application that would, to be sure, be called for if I meant to cognize myself. But for now I wish to be aware of myself merely as something that thinks; the way in which my own self is given in intuition I leave aside, and in that respect it might well be, for me who does the thinking though not so far as I think, nothing more than appearance; when I am aware of myself in the act of mere thought I am the being itself, yet thereby nothing about it is yet given to me for thought.

The proposition, though: I think, taken to mean as much as: I exist thinking, is no mere logical function, but instead determines the subject (which at once is then also object) in regard to existence, and it can have no place apart from inner sense, whose intuition invariably yields the object not as a thing in itself but only as appearance. In it there is accordingly no longer merely the spontaneity of thought, but a receptivity of intuition as well, that is, my thinking of myself as brought to bear on the empirical intuition of that very same subject . In this latter intuition, then, the thinking self would be obliged to look for the conditions under which it employs its logical functions as categories of substance, of cause, and so on, so as to mark itself out as an object in its own right not merely by means of the I, but also to determine the mode of its existence, that is, to cognize itself as noumenon—which, however, cannot be done, since the inner empirical intuition is sensible and hands over nothing beyond data of appearance, data that contribute nothing to the object of pure consciousness for a knowledge of its separate existence, and can be of use solely for the aims of experience.

But grant that there should turn up further on—not within experience, but within certain laws of the pure use of reason (laws that are more than merely logical rules) which stand fixed a priori and bear on our existence—an occasion to presuppose ourselves, wholly a priori and as regards our own existence, to be legislative and to be ourselves the determiners of that existence: then a spontaneity would thereby come to light through which our actuality could be determined without any call for the conditions of empirical intuition; and at this point we would come to realize that within the consciousness of our existence there lies enclosed a priori a certain something, one able to help determine our existence—everywhere determinable, otherwise, only through the senses—as regards a particular inner power, and in relation to an intelligible (albeit merely thought) world.

But this would nonetheless not in the least advance any of the attempts made in rational psychology. For through that admirable faculty which the consciousness of the moral law first reveals to me I would indeed have a principle for the determination of my existence, one that is purely intellectual, but by means of which predicates? By none other than those that have to be supplied to me within sensible intuition; and so I would end up back once more at the spot where I stood in rational psychology, namely at the requirement for sensible intuitions in order to lend meaning to my concepts of the understanding—substance, cause, and the like—by which alone I am able to have cognition of myself; those intuitions, however, can never carry me out past the field of experience. Yet in regard to practical use—which after all is always aimed at objects of experience—I would still be permitted to apply these concepts to freedom and to the subject thereof, following the meaning analogous to their theoretical use, inasmuch as by them I take to be meant nothing but the logical functions of subject and of predicate, of ground and of consequence, conformably to which the actions or effects come to be determined, in keeping with those laws, in such a way that they admit of being explained—jointly with the laws of nature—always in conformity with the categories of substance and of cause, even should they arise from an altogether different principle. This was meant to be said only in order to forestall the misunderstanding to which the doctrine of our self-intuition as appearance is easily exposed. In what follows there will be occasion to make use of it.

Chapter 2. The Antinomy of Pure Reason

We showed, in the introduction to the present portion of our work, that all transcendental illusion of pure reason has its basis in dialectical inferences, for which logic furnishes the schema by way of the three formal kinds of inference of reason in general, roughly as the categories, for their part, encounter their logical schema within the four functions belonging to every judgment. The first kind of these ratiocinating inferences was directed at the unconditioned unity of the subjective conditions of all representations whatever (the subject, that is, or the soul), corresponding to the categorical inferences of reason, whose major premise, in its capacity as principle, asserts the relation that a predicate bears to a subject. The second kind of dialectical argument will therefore, following the analogy with hypothetical inferences of reason, make the unconditioned unity of the objective conditions in appearance into its content, just as the third kind, which is to come up in the next chapter, takes for its theme the unconditioned unity of the objective conditions of the possibility of objects in general.

What is noteworthy, however, is that the transcendental paralogism brought about only a one-sided illusion with respect to the idea concerning the subject of our thinking, while for asserting the opposite not the least illusion, drawn from concepts of reason, will present itself. The advantage falls entirely to the side of pneumatism, even though pneumatism cannot deny its inherited flaw of evaporating, for all the illusion in its favor, into sheer mist under critique's trial by fire.

Things fall out quite otherwise once we bring reason to bear on the objective synthesis of appearances, where, though it supposes it can assert its principle of unconditioned unity with a great show of plausibility, it soon entangles itself in contradictions of such a kind that it finds itself constrained, in its cosmological intent, to withdraw from its demand.

For at this point human reason displays a new phenomenon, namely: a thoroughly natural antithetic, one over which no one need brood or contrive to set snares, but into which reason lapses of itself, and indeed unavoidably, whereby it is preserved, on the one hand, from the slumber of an imagined conviction such as a merely one-sided illusion produces, yet is at the same time led into the temptation either of surrendering to a skeptical despair, or of assuming a dogmatic defiance and stubbornly fixing its mind on certain assertions while refusing to grant the grounds of the opposite a hearing and their due. Both spell the death of a sound philosophy, though the former could perhaps still be termed the euthanasia of pure reason.

Before we allow the scenes of the schism and of the disruptions to be witnessed that this conflict of laws (antinomy) of pure reason gives rise to, we mean to set down certain considerations capable of elucidating and vindicating the method that we employ in dealing with our object. To all transcendental ideas, insofar as they have to do with the absolute totality within the synthesis of appearances, I give the name world-concepts, partly because of just this unconditioned totality (upon which the concept of the world-whole itself reposes, though that concept is in turn only an idea), and partly because they bear merely on the synthesis of appearances, and hence on the empirical synthesis, whereas the absolute totality in the synthesis of the conditions of all possible things whatever will give rise to an ideal of pure reason, one wholly distinct from the world-concept, albeit standing in relation to it. Accordingly, just as the paralogisms of pure reason supplied the foundation for a dialectical psychology, so likewise the antinomy of pure reason is to hold up before us the transcendental principles of a putative pure (rational) cosmology, not so as to find them valid and adopt them as our own, but rather—as the very designation of a conflict of reason already makes plain—so as to present them, being an idea that admits of no reconciliation with appearances, in their dazzling yet deceptive illusion.

Section 1. System of cosmological ideas

Now, if we are to enumerate these ideas according to a principle and with systematic precision, we must first observe that pure and transcendental concepts can spring from the understanding alone, that reason of itself brings forth no concept whatever, but does no more than free a concept of the understanding from the inescapable restrictions of a possible experience, seeking thereby to enlarge it beyond the limits of the empirical, though still in conjunction with the empirical. This comes about as follows: on the side of the conditions (those beneath which the understanding brings every appearance under synthetic unity), reason lays claim, for some given conditioned, to absolute totality, and in this way a category is raised into a transcendental idea, the aim being to endow the empirical synthesis with absolute completeness by prolonging it up to the unconditioned (which is met with never in experience but solely in the idea). Reason's demand here proceeds from this principle: once the conditioned is posited, the entire sum of its conditions is likewise given, and therewith the utterly unconditioned as well, through which the conditioned was alone possible. Thus the transcendental ideas will, first, amount to nothing more than categories enlarged up to the unconditioned, and they will let themselves be set out in a table ordered by the titles of the categories. Secondly, however, not every category will serve this purpose, but only those whose synthesis makes up a series—and indeed a series of conditions subordinated one to another (not coordinated) running toward a conditioned. Reason exacts absolute totality only to the degree that it bears upon the ascending series of conditions belonging to a given conditioned, and thus not where what is at issue is the descending line of consequences, or the aggregate of coordinated conditions leading to those consequences. For with respect to the given conditioned the conditions are already presupposed and must be taken as given together with it; whereas, seeing that consequences do not render their conditions possible but on the contrary presuppose them, one may, as one advances toward the consequences (or descends from a given condition to what it conditions), stay unconcerned whether the series terminates or not, so that the question of its totality is in general no presupposition of reason whatever.

In just this way one necessarily represents a stretch of time, wholly run out up to the present moment, as itself given as well (albeit not determinable by us). But as regards time still to come, since it forms no condition for reaching the present, it is—for the purpose of comprehending the present—entirely indifferent what we care to make of future time, whether we would have it stop somewhere or run on without end. Take the series m, n, o, where n is given as conditioned in relation to m and yet at the same time as the condition of o; let the series ascend from the conditioned n up to m (l, k, i etc.) and equally descend from the condition n down to the conditioned o (p, q, r etc.): then I must presuppose the first series if I am to regard n as given, and, according to reason (the totality of conditions), n is possible only through that series, whereas its possibility in no way depends upon the following series o, p, q, r, which for that reason could be regarded not as given but merely as dabilis.

The synthesis of a series on the side of the conditions—starting from the condition nearest the given appearance and proceeding to ever more remote conditions—I shall term the regressive synthesis; the one that goes forward on the side of the conditioned, from the nearest consequence out to the more remote ones, I shall term the progressive synthesis. The former of these runs off into the antecedentia, the latter into the consequentia. The cosmological ideas, accordingly, concern themselves with the regressive synthesis in its totality, running off into the antecedentia and not into the consequentia. Should the latter be the case, we have an arbitrary and by no means necessary problem of pure reason, for to comprehend fully what is given in the appearance we require its grounds, but not its consequences.

Now, to set up the table of ideas in correspondence with the table of categories, we begin with the two primordial Quanta of all our intuition, namely time and space. Time is in and of itself a series (indeed the formal condition of every series), and so within it, relative to a given present, the antecedentia as conditions (the past) must be told apart a priori from the consequentibus (the future). It follows that the transcendental idea of an absolute totality in the series of conditions for a given conditioned reaches only over all bygone time. In keeping with the idea of reason, the entire course of elapsed time is of necessity thought as given, being the condition of the given moment. Space, on the other hand, contains in itself no distinction between progressus and regressus, for it makes up an aggregate and no series, its parts being all together at once. The present point in time I could, relative to time past, view only as conditioned and never as a condition of that past, since this moment arises in the first place solely through elapsed time (or rather through the elapsing of the time that went before). But because the parts of space stand not in subordination but in coordination to one another, no one part is the condition of another's possibility, and space does not, as time does in itself, make up a series. Still, the synthesis of space's manifold parts, whereby we apprehend it, does proceed successively; it therefore takes place in time and harbors a series. And since in this series of aggregated spaces (the feet in a rod, say), reckoning from a given one, each further space added in thought is invariably the condition of the boundary of the one before, the measuring of a space too must count as a synthesis of a series of conditions running to a given conditioned; save only that the side of the conditions is not, in itself, distinguished from the side on which the conditioned lies, so that in space regressus and progressus appear to coincide. But since one part of space is not given by means of another, only bounded by it, we must to that extent regard every bounded space as itself conditioned as well, presupposing a further space as the condition of its boundary, and so onward without end. In respect of bounding, then, advance in space is likewise a regressus, and the transcendental idea of the absolute totality of synthesis in the series of conditions applies to space as well; I may therefore ask after the whole of appearance in space no less than after the whole of it in time gone by. Whether an answer to any of this is possible at all will be something to settle later on.

Secondly, the reality in space—that is, matter—is a conditioned; its inner conditions are its parts, and the parts of those parts its more distant conditions, so that here a regressive synthesis obtains, the absolute totality of which reason demands—a totality attainable in no other way than through a completed division, by which the reality of matter disappears either into nothing or else into something that is matter no longer, namely the simple. Here too, then, we have a series of conditions and an advance toward the unconditioned.

Thirdly, as for the categories of the real relation among appearances, the category of substance together with its accidents does not lend itself to a transcendental idea; that is to say, reason has no ground to travel back regressively toward conditions in its case. For accidents, so far as they inhere in one and the same substance, stand coordinate with one another and form no series. And in relation to the substance they are not, strictly speaking, subordinate to it; they are rather the very mode in which the substance itself exists. The one thing here that might still look like an idea of transcendental reason would be the concept of the substantiale. Yet since this means nothing beyond the concept of an object as such that subsists—so far as one thinks in it the mere transcendental subject stripped of all predicates—while what is under discussion here is only the unconditioned within the series of appearances, it is evident that the substantiale can form no link in that series. The very same holds of substances in mutual community, which are mere aggregates and possess no exponent of a series, inasmuch as they are not subordinated one to another as conditions of their possibility—as could well be said of spaces, whose limit was never fixed in itself but always by another space. There remains, then, only the category of causality, which sets before us a series of causes for a given effect, one in which we can climb from that effect, as conditioned, up to those causes, as its conditions, and so give answer to the question of reason.

Fourthly, the concepts of the possible, the actual, and the necessary give rise to no series, except only to the extent that the contingent in existence must at all times be viewed as conditioned and, by the rule of the understanding, points back to a condition, under which it becomes necessary to point on to a still higher one, until reason lights upon the unconditioned necessity solely within the totality of this series.

Thus there are, all told, no more than four cosmological ideas, answering to the four titles of the categories, once one picks out those categories that necessarily bring a series with them in the synthesis of the manifold.

The first point to be noted is this: that the idea of absolute totality has to do with nothing beyond the exposition of appearances, and thus not with the pure concept of the understanding of a whole of things as such. Appearances, then, are here taken as given, and reason calls for the conditions of their possibility to be supplied in absolute completeness, so far as those conditions make up a series—hence for a synthesis that is complete without qualification (complete, that is, in every respect), by means of which the appearance admits of being expounded under laws of the understanding.

Secondly, what reason genuinely seeks in this synthesis of conditions—carried on step by step through the series, and regressively at that—is really nothing but the unconditioned: the completeness, so to speak, of the row of premises that, taken together, presuppose no further premise. This unconditioned is, at every turn, already contained within the absolute totality of the series whenever one pictures that series to oneself in imagination. Yet a synthesis thus brought to unqualified completion is, once again, no more than an idea; for one cannot tell, at least beforehand, whether anything of the kind is even possible in the case of appearances. If one pictures everything by means of pure concepts of the understanding alone, apart from the conditions of sensible intuition, then one may say straight out that, given a conditioned, the whole series of conditions subordinate to one another is given along with it; for the former is had only through the latter . With appearances, however, we meet a peculiar restriction on the way in which their conditions come to be given—namely, through a successive synthesis running across the manifold of intuition, one that is supposed to reach completeness in the regress. Whether such completeness is in fact possible on the side of sensibility remains a problem. The idea of that completeness, all the same, resides in reason quite apart from whether or not empirical concepts adequate to it can be attached. So, since the unconditioned is necessarily embraced within the regressive synthesis of appearance's manifold when taken in absolute totality (a synthesis guided by the categories, which present that manifold as a series of conditions running to a given conditioned)—and here one may leave undetermined whether and how such totality is to be achieved—reason adopts the course of setting out from the idea of totality, although its genuine final aim is the unconditioned, whether of the whole series or of a part of it.

This unconditioned now admits of being thought in either of two ways: either as residing simply in the entire series, in which case every member without exception would be conditioned and only the series as a totality would be unconditioned outright—and then the regress is termed infinite; or else the absolutely unconditioned is only some one part of the series, to which the remaining members are subordinate, while it itself falls under no further condition.⁴² In the former case the series, a parte priori, is boundless (without beginning), i.e. infinite, and nonetheless given in full, though the regress within it is never completed and can be styled infinite only potentialiter. In the latter case the series possesses a first member—one called, with respect to time elapsed, the beginning of the world; with respect to space, the boundary of the world; with respect to the parts of a whole given within its limits, the simple; with respect to causes, absolute self-activity (freedom); and with respect to the existence of alterable things, absolute necessity of nature.

We have two terms at our disposal—world and nature—which now and then run into each other. The first denotes the mathematical whole of all appearances together with the totality of their synthesis alike in the great and in the small, that is, in the progress of that synthesis both by composition and by division. This very same world, however, we call nature⁴³ once it is regarded as a dynamic whole—when we look not to the aggregation of things in space or time (a way of constituting it as a magnitude) but to the unity in the existence of appearances. At this point the condition of whatever happens we name the cause; the unconditioned causality of that cause within the appearance we name freedom; and the conditioned causality, by contrast, is what, in the narrower sense, we name a cause in nature. The conditioned in existence generally we call contingent, the unconditioned we call necessary. The unconditioned necessity that belongs to appearances may be termed a necessity of nature.

The ideas now occupying us I termed cosmological a moment ago, partly because "world" signifies the sum of all appearances and our ideas likewise aim only at the unconditioned among appearances, and partly too because the word "world", taken transcendentally, denotes the absolute totality of the sum of existing things, and it is on the completeness of the synthesis alone (though strictly only in the regress toward the conditions) that we fix our attention. Bearing in mind, moreover, that these ideas are one and all transcendent, and that, although they do not overstep their object—appearances—as to kind, having to do merely with the world of sense (not with noumena), they nonetheless push the synthesis to a degree exceeding every possible experience, I think one may quite aptly call them, collectively, world-concepts. In view of the difference between the mathematically and the dynamically unconditioned toward which the regress is directed, I would, even so, reserve the term world-concepts (of the world in the great and the small) for the first two in a narrower sense, calling the remaining pair transcendent concepts of nature instead. For the present this distinction carries no special weight, but as we go on it may take on greater importance.

Section 2. Antithetic of pure reason

If a thetic is any aggregate of dogmatic doctrines, then by antithetic I understand not dogmatic assertions of the contrary, but rather the conflict of cognitions that are dogmatic in appearance (thesin cum antithesi), without conceding to any one of them a superior claim to assent over another. The antithetic thus concerns itself not at all with one-sided assertions, but instead considers universal cognitions of reason solely with respect to their mutual conflict and the causes of that conflict. The transcendental antithetic is an investigation concerning pure reason's antinomy, together with its causes and its outcome. If we use our reason not merely for the application of the principles of the understanding to objects of experience, but venture to extend those principles beyond the boundary of the latter, then rationalizing doctrines arise that can look for no confirmation in experience and need dread no refutation from it, and each of which is not only free from contradiction in itself but even finds in the nature of reason conditions of its necessity—only that, unfortunately, the opposite has grounds for its assertion on its own side that are just as valid and necessary.

The questions that naturally present themselves in such a dialectic of pure reason are therefore these: 1. In the case of which propositions pure reason is in fact unavoidably subject to an antinomy. 2. On what causes this antinomy rests. 3. Whether, and in what manner, a path to certainty nonetheless remains open to reason under this contradiction.

A dialectical doctrine of pure reason must accordingly have about it this feature, distinguishing it from all sophistical propositions, that it does not concern an arbitrary question raised only for some chosen purpose, but rather one which every human reason must necessarily encounter in its progress; and, secondly, that together with its opposite it carries with it not merely a contrived illusion, which disappears at once when one sees through it, but a natural and unavoidable illusion that, even when one is no longer taken in by it, still continues to delude, though not to cheat, and so can indeed be rendered harmless but never eradicated.

A dialectical doctrine of this kind will bear not on the understanding's unity within concepts of experience, but on reason's unity within mere ideas—and the conditions of that unity, given that they must first, as a rule-governed synthesis, be congruent with the understanding while yet, as the absolute unity of this same synthesis, being congruent with reason, will turn out too large for the understanding whenever they are adequate to reason's unity, and too small for reason whenever they fit the understanding; whence a conflict is bound to spring that admits of no avoidance, begin the matter as one may.

These rationalizing assertions accordingly throw open a dialectical arena of combat, in which the upper hand stays with whichever party is allowed to make the attack, while the one forced to proceed by mere defense is bound to lose. Hence even doughty knights, whether they pledge themselves to the good cause or the bad, are sure to carry off the victor's wreath, provided only that they see to it that theirs is the prerogative of striking the final blow, with no obligation to endure a renewed assault from their opponent. One can easily imagine that this arena has from time immemorial been entered often enough, that many victories were won on both sides, but that, as regards the last one, which decided the matter, care was always taken so that the champion of the good cause alone kept the field, by forbidding his opponent to take up arms any further. As impartial umpires we must set entirely aside the question whether the cause over which the disputants do battle be the good one or the bad, and let them first thresh out their quarrel among themselves. Perhaps, after they have wearied one another more than they have done any harm, they will of themselves come to see the nullity of their quarrel and go their separate ways as good friends.

This method of watching a dispute among assertions play out, or rather of prompting it oneself—not in order to decide finally in favor of one side or the other, but in order to investigate whether its object may not perhaps be a mere phantom that each grasps at in vain and from which none can gain anything even were it not resisted at all: this procedure, I say, may be called the skeptical method. It is wholly different from skepticism, that principle of a contrived and scientific ignorance which saps the very groundwork of all cognition in order, so far as it can, to leave nowhere any dependability or security in cognition. For the skeptical procedure is directed at certainty: in a controversy meant honestly by both sides and conducted with insight, it looks to locate the point of misunderstanding, so that, like sagacious lawgivers, it may draw for itself, from the perplexity of judges in legal suits, a lesson about what is deficient and not precisely fixed in their statutes. The antinomy that comes to light in applying the laws is, with our restricted wisdom, the best trial of legislative craft, since it thereby alerts reason—which in abstract speculation does not easily catch its own false steps—to the factors at work in fixing its principles.

Yet this skeptical method belongs, in its essence, to transcendental philosophy and to it alone; in every other domain of investigation it may perhaps be done without, but not here. Within mathematics an employment of it would be nonsensical, for there no false claims can hide themselves and slip out of sight, seeing that the demonstrations must always advance along the thread of pure intuition, and that by way of a synthesis at every point evident. In experimental philosophy a doubt that postpones judgment may indeed be useful, yet at least no misunderstanding is possible that could not readily be removed, and the ultimate means of deciding the dispute must in the end lie in experience, whether they come to be found early or late. Morality can present all its principles collectively, also in concreto, together with their practical consequences, at least in possible experiences, and thereby avoid the misunderstanding of abstraction. The transcendental assertions, on the other hand, which presume to insights reaching out past the whole field of every possible experience, are situated neither such that their abstract synthesis might be exhibited in some intuition a priori, nor such that the misunderstanding could be brought to light through any experience whatever. Transcendental reason, then, permits no other touchstone than the attempt to unite its assertions with one another and hence, beforehand, the free and unhindered contest of them among themselves—and this contest we shall now set in motion.⁴⁴

The Antinomy of Pure Reason

First Conflict of the Transcendental Ideas.

Thesis.

The world has a beginning in time, and as regards space it likewise lies confined within bounds.

Proof.

For assume that, in respect of time, the world has no beginning: then, up to any given point in time, an eternity has run out, and with it an infinite series of the successive states of the world's things has gone by. Yet just here lies the infinity of a series — namely, that no successive synthesis can ever bring it to completion. An infinitely elapsed world-series is therefore impossible, and so a beginning of the world stands as a necessary condition of its existence — the point to be established first.

Turning to the second, assume once more the reverse, and the world becomes an infinite given whole made up of things that exist all at once. Now the magnitude of a quantum that no intuition supplies within certain bounds ⁴⁵ can be thought by us in no way but through a synthesis of the parts, and the totality of such a quantum only through a synthesis carried to its end, or by adjoining the unit to itself over and over.⁴⁶ Hence, to conceive the world that occupies every space as one whole, one would have to take the successive synthesis of an infinite world's parts to be finished — that is, an infinite time would have to count as spent in the tallying of all coexisting things; and this cannot be. It follows that an infinite aggregate of actual things can count neither as a given whole nor, therefore, as something given all at once. A world is on this account not infinite in its spatial extension, but shut within its bounds — and this was the second point.

Antithesis.

The world has neither a beginning nor spatial limits, but is infinite alike in respect of time and of space.

Proof.

For posit the following: it has a beginning. Since a beginning is an existence ahead of which lies a time wherein the thing is not, some time must have run before it in which the world was not — that is, an empty time. But within an empty time nothing whatever can come to be: for no stretch of such a time carries in itself, ahead of any other, any distinguishing condition of existence over that of non-being (whether one supposes it to arise of itself or through some other cause). So although many a series of things may well begin within the world, the world itself can begin at no point, and is thus, in respect of past time, infinite.

As to the second point, grant first the reverse — namely, that the world is, in respect of space, finite and bounded: it then sits within an empty space that has no bounds. One would thereby meet with not merely a relation of things within space, but also a relation of things to space. But since the world is an absolute whole beyond which no object of intuition, and so no correlatum of the world, is met with for it to stand toward, the world's relation to empty space would come to a relation of it toward no object at all. Such a relation, however — and with it the world's confinement by empty space — is nothing; the world is accordingly in no way bounded in space, that is, it is infinite as regards its extension.⁴⁷

Remark on the First Antinomy.

I. On the Thesis.

In framing these mutually opposed arguments I have looked for no sleight of hand by which to mount, as people say, a lawyer's proof — one that turns the adversary's incaution to its own profit, that is happy to let his appeal to a misread statute pass, and then rears its own unwarranted claims on the refutation of it. Every one of these proofs is instead derived from the nature of the case, with no use made of the advantage that the dogmatists' faulty inferences on either side might have afforded us.

I might equally have furnished a mere semblance of proof for the thesis by sending on ahead, in the dogmatists' habitual manner, a defective concept of the infinity of a given magnitude. Infinite names a magnitude than which none greater is possible (that is, none exceeding the multitude of a given unit that it contains). But no multitude is the largest, for one may forever adjoin a further unit or several. An infinite given magnitude, and thus a world infinite alike in its elapsed series and in its extension, cannot be; the world is therefore bounded on either hand. In this fashion I might have carried through my proof — save that the concept fails to square with what an infinite whole is taken to mean. It tells us nothing of how great the whole is, so that its concept is no concept of a maximum; it registers merely the whole's relation to some freely chosen unit, in respect of which it exceeds every number. As that unit is taken larger or smaller, the infinite would come out larger or smaller; but the infinitude itself, grounded as it is wholly in the relation to this given unit, would stay unaltered throughout — though the whole's absolute magnitude goes thereby quite uncognized, which is in any case not our concern here.

The genuine (transcendental) concept of infinity runs thus: that the successive synthesis of the unit in traversing a quantum can never reach its end.⁴⁸ What follows from this, and with full security, is that up to a given (the present) point in time no eternity of successive actual states can have run its course, and hence that the world must have had a beginning.

With the thesis's second part, the trouble of a series at once infinite and yet elapsed does fall away; for the manifold of a world infinite in extension is given all at once. But to conceive the totality of such a multitude — since we can lean on no bounds that would of themselves mark this totality out in intuition — we are bound to render account of our concept, which here cannot pass from the whole down to the fixed multitude of the parts, but has to make out the possibility of a whole by way of the parts' successive synthesis. And because this synthesis would make up a series never to be finished: no totality can be conceived either ahead of it or, consequently, through it. For here the very concept of totality is the representation of a synthesis of the parts carried through to the end, and this carrying-through — hence the concept of it too — is impossible.

II. On the Antithesis.

The proof that the given world-series and the sum-total of the world are infinite rests on this: that, were it otherwise, an empty time — and an empty space no less — would have to make up the world's boundary. Now I am well aware that shifts are looked for against this consequence, the claim being that a boundary of the world in respect of time and space is quite possible without one's needing to posit an absolute time before the world's beginning or an absolute space spread out beyond the actual world; which cannot be. With the latter half of this view, held by the philosophers of the Leibnizian school, I am altogether content. Space is nothing more than the form of outer intuition — no actual object open to outward intuition, and no correlatum of the appearances, but the appearances' own form. Space, then, taken absolutely (on its own), can figure as nothing determinative in the existence of things, since it is no object whatever, but only the form that possible objects take. Things, then, as appearances do indeed determine space — that is, out of every predicate it might carry (magnitude and relation) they bring it about that this one or that belongs to actuality; conversely, though, space as a self-subsisting something cannot determine the actuality of things in respect of magnitude or shape, since it is in itself nothing actual. A space (full or empty)⁴⁹ may thus well be bounded by appearances, yet appearances cannot be bounded by an empty space lying outside them. Exactly this holds of time as well. Grant all of this, and it remains beyond dispute that one is bound to posit these two non-things — the empty space outside and the empty time before the world — the moment one posits a world-boundary, whether in respect of space or of time.

For the way out by which the consequence is dodged — the consequence, as we put it, that if the world has limits (in time and space) the infinite void must determine the existence of actual things as to their magnitude — comes down, on the quiet, to just this: that in place of a world of sense one imagines who knows what intelligible world, and in place of the first beginning (an existence ahead of which lies a time of non-being) one imagines an existence at large that presupposes no further condition within the world, that in place of the boundary of extension one imagines bounds to the world-whole, and so slips clear of time and space. But here it is the mundus phaenomenon alone, and its magnitude, that is at issue — something from whose supposed conditions of sensibility one cannot abstract in the slightest without cancelling its very being. The world of sense, should it be bounded, lies of necessity within the infinite void. Should one wish to drop this, and thereby space as such, as the a priori condition of the possibility of appearances, the whole world of sense drops with it. It is this, and this alone, that our problem hands us. The mundus intelligibilis is nothing beyond the general concept of a world as such, in which one abstracts from every condition of intuiting it, and with respect to which, in consequence, not one synthetic proposition — affirming or denying — can be reached.

The Antinomy of Pure Reason

The Second Conflict among the Transcendental Ideas.

Thesis.

In the world, each and every composite substance is made up of simple parts, and nothing whatever exists except what is simple or what has been put together out of the simple.

Proof.

For grant that composite substances were not built up from simple parts: then, once every composition had been cancelled in thought, there would be left neither any composite part nor—there being no simple parts—any simple one, and hence nothing at all, so that no substance would ever have been given in the first place. So either it is impossible to cancel all composition in thought, or, once such cancellation has occurred, something subsisting apart from any composition whatever, that is, the simple, must remain over. In the former case, though, the composite would once more fail to be made of substances (for with substances composition is but a contingent relation among them, one without which they would still have to subsist as, in their own right, abiding beings). And since this case runs counter to what was presupposed, only the second option is left standing: that the substantial composite found in the world is built up from simple parts.

It follows from this at once that the world's things are, without exception, simple beings, that their composition is no more than an outward condition of them, and that, although we can never see the elementary substances entirely freed and isolated from this condition of combination, reason is nonetheless bound to think them as the primary subjects of all putting-together, and thus, ahead of it, as simple beings.

Antithesis.

No composite thing anywhere in the world is built up from simple parts, and nothing simple exists in it at all.

Proof.

Posit the following: a composite thing (taken as a substance) is built up out of simple parts. Since any external relation whatever—and therefore any composition of substances too—can obtain only in space, the space a composite occupies must be built up from exactly as many parts as the composite itself is. Now space is built up not from simple parts but from spaces. Every part of the composite, then, has to take up a space. Yet the utterly first parts of anything composite are simple. The simple, accordingly, takes up a space. But since anything real that takes up a space encloses within it a plurality of mutually external parts, and is on that account composite—and, being a real composite, is made up not of accidents (for accidents cannot stand external to one another apart from a substance) but of substances—the simple would turn out to be a substantial composite, which is self-contradictory.

The antithesis's second claim—that within the world nothing whatever simple exists—is intended here to carry just this import: that the existence of what is absolutely simple can be exhibited through no experience or perception, outer or inner alike, so that the absolutely simple amounts to a mere idea, one whose objective reality is never exhibitable in any possible experience, and which accordingly, in laying out the appearances, is left wholly without application or object. For suppose we could locate, for this transcendental idea, some object of experience: then the empirical intuition of one or another object would have to be recognized as containing utterly no manifold whose members lie apart from one another and are bound together into a unity. Now since one cannot legitimately move from the failure to be conscious of such a manifold to its outright impossibility in every intuition of an object, while that latter impossibility is precisely what absolute simplicity demands, it follows that no perception, of whatever sort, can yield a valid inference to such simplicity. Since, therefore, no object that is absolutely simple can ever be met with in any possible experience, and since the sensible world has to be taken as the entire compass of all possible experiences, it contains nowhere within it anything simple at all.

This second claim of the antithesis reaches much further than the first: whereas the first merely bars the simple from the intuition of the composite, this one clears it away out of the whole of nature; which is why it admitted of proof not from the concept of a given object of outer intuition (the composite), but rather from that object's relation to a possible experience as such.

Remark on the Second Antinomy.

I. On the Thesis.

Whenever I talk of a whole that of necessity is built up from simple parts, all I mean by it is a substantial whole in the strict sense of a Compositum, that is, the contingent unity of a manifold that, once severally (at least in thought) given, is brought into a mutual connection and so makes up a single thing. Space, strictly speaking, ought to be termed not a Compositum but a Totum, since its parts become possible only within the whole, rather than the whole becoming possible by way of its parts. If anything, it might be styled a Compositum ideale, though never a reale. Still, this is nothing but a nicety. Because space is not anything composed of substances (nor even of real accidents), it follows that, should I cancel all composition within it, nothing—not so much as the point—can be left behind; for the point has its possibility solely as the limit of a space, and so of a composite . Space and time, accordingly, are not built up from simple parts. Whatever pertains only to the state of a substance—even where it possesses a magnitude, as alteration does—is likewise not built up from the simple; that is to say, a given degree of alteration does not come about by the accumulation of many simple alterations. Our move from the composite to the simple carries weight only for things that subsist on their own. Accidents of a state, by contrast, have no subsistence on their own. One may thus, with little trouble, wreck the proof for the necessity of the simple as the components of every substantial composite—and with it wreck one's cause altogether—by stretching it too far and insisting on its validity for everything composite indiscriminately, as has more than once actually been done.

For the rest, what I address here is only the simple insofar as it is of necessity given within the composite, seeing that the composite admits of being resolved into it as into its own components. The strict sense of the term Monas (as Leibniz employed it) really ought to reach only as far as the simple that is directly given as a simple substance—in self-consciousness, for instance—and not the element of a composite, which would be more aptly termed the Atomus. And because it is only with a view to the composite that I mean to establish simple substances as its elements, I might well label the thesis of the second antinomy a transcendental atomistics. But since that term was long ago put to use in naming a particular way of accounting for corporeal appearances (molecularum), and hence takes empirical concepts for granted, the principle may just as well be called the dialectical principle of monadology.

II. On the Antithesis.

Against this proposition of the infinite divisibility of matter—whose supporting ground is purely mathematical—the monadists raise objections that render themselves suspect from the outset, in that they will not grant the plainest mathematical demonstrations the standing of insights into how space is constituted (space being, in truth, the formal condition of the possibility of all matter), but treat them instead as nothing more than conclusions spun from abstract yet arbitrary concepts that admit of no application to real things. As though it were so much as conceivable to invent some mode of intuiting other than what the original intuition of space affords us, and as though space's a priori determinations did not thereby bear at once on all that is possible for the sole reason that it fills this very space. Were one to give them a hearing, then over and above the mathematical point—simple, yet no part, being merely the limit of a space—one would have to conceive of physical points as well, which, though likewise simple, enjoy the distinction of filling space, as its parts, through their bare aggregation. I shall not rehearse here the ordinary and lucid refutations of this incongruity, which are to be had in plenty—since it is in any event altogether pointless to try, with nothing but discursive concepts, to argue away the self-evidence of mathematics—and shall observe only this: that where philosophy makes trouble for mathematics on this point, it does so because it loses sight of the fact that the question here concerns nothing but appearances and the conditions of them. Here, however, it will not do merely to supply, alongside the pure concept of the understanding of the composite, the concept of the simple; what is required is that, for the intuition of the composite (that is, of matter), one supply the intuition of the simple—and this, given the laws of sensibility, and therefore in the case of objects of the senses as well, is flatly impossible. Thus one may always grant, of a whole made of substances that is conceived by pure understanding alone, that ahead of any composition of it we must already possess the simple; and yet this fails to hold of the totum substantiale phaenomenon, which, being an empirical intuition in space, brings with it the unavoidable feature that not one of its parts is simple, for the reason that no part of space is simple. The monadists, to be sure, have shown enough finesse in seeking to sidestep this difficulty: they take space not to be a condition under which the objects of outer intuition (bodies) are possible, but conversely posit those bodies, together with the dynamical relation of substances at large, as that which makes space itself possible. Yet our only concept of bodies is one of them as appearances, and precisely as appearances they cannot but require space beforehand, since space is what first makes any outer appearance possible at all; the loophole is thus of no avail, having in any case been adequately blocked earlier, in the Transcendental Aesthetic. If they were things in themselves, the monadists' proof would carry the day after all.

What is distinctive about the second dialectical assertion is that it faces a dogmatic assertion set against it—the one assertion, among all the sophistical ones, that ventures to demonstrate palpably, upon an object of experience, the actuality of something we ranked above as belonging only to the transcendental ideas, namely the absolute simplicity of substance: to wit, that inner sense's object, the thinking I, is a wholly simple substance. Without engaging with this at present (having examined it at greater length above), I will note only the following: that whenever something is thought simply as an object, with no synthetic determination of its intuition added on (which is just what occurs with the entirely naked representation: I), then naturally no manifold and no putting-together can be discerned in a representation of that sort. And since, besides, the predicates by which I think this object are merely intuitions belonging to inner sense, nothing can turn up in it that would attest to a manifold lying apart from one another, and thereby to a real composition. It is thus purely a consequence of self-consciousness that, since the subject doing the thinking is at once its own object, it is incapable of dividing itself (however divisible the determinations that inhere in it); for taken with regard to itself, every object is an absolute unity. All the same, were this subject to be regarded externally, as an object of intuition, it would after all quite likely exhibit composition in its appearance. And that is precisely how it must always be regarded whenever one wishes to determine whether or not there is within it a manifold lying apart from one another.

Of the Antinomy of Pure Reason

Third Conflict of the Transcendental Ideas.

Thesis.

Causality according to laws of nature is not the sole causality from which the world's appearances, taken all together, admit of being derived. For explaining these appearances it is furthermore necessary to assume a causality through freedom.

Proof.

Assume that no causality exists beyond that which conforms to nature's laws; in that case everything that happens has for its presupposition an antecedent state, upon which it ensues unfailingly by a rule. Now this antecedent state must itself be something that came to be (something that arose within time, not having been before); for had it subsisted from all eternity, its consequence likewise would not first have originated but would always have been. Hence the causality belonging to the cause by which something happens is itself a thing that has occurred, one that under the law of nature once more requires an antecedent state along with its causality, which state in turn requires a yet earlier one, and so on. So should all events come to pass under nothing but the laws of nature, there is then, at every juncture, only a subaltern start and never a first, so that on the side of the causes descending one from another the series achieves no completeness at all. Yet this is exactly wherein the law of nature consists: that nothing comes about save through a cause determined with sufficiency a priori. Thus the proposition that every causality is possible solely under nature's laws falls into contradiction with itself when taken in its unlimited universality, and this universality can therefore not be accepted as the only one.

There must, accordingly, be posited a causality whereby something comes to pass while its cause is not in turn fixed, by some further cause going before it, under necessary laws—that is to say, an absolute spontaneity on the part of the causes, a capacity to set going of itself a series of appearances proceeding by natural laws, and thus transcendental freedom, in the absence of which even within nature's course the succession of appearances on the causal side never attains completeness.

Antithesis.

There is no freedom; everything in the world, on the contrary, takes place merely under laws of nature.

Proof.

Posit that there existed, in the transcendental sense, a freedom functioning as a peculiar species of causality by which the world's events might be brought about—that is, a power to inaugurate absolutely a state, and thereby a whole series of consequences flowing from it; then it is not merely a series that would commence through this spontaneity, but the very determining of this spontaneity toward generating the series, i.e. the causality itself, that would set in absolutely, so that nothing at all precedes whereby this occurring deed is fixed under abiding laws. But any beginning of acting whatever has for its presupposition a state in which the cause is not yet acting; and a dynamically first onset of the action presupposes a state bearing no causal connection at all to the preceding state of that self-same cause, i.e. one arising in no manner out of it. Transcendental freedom, accordingly, runs counter to the law of causality, and any such binding-together of the successive states of operative causes—a linkage that permits no unity of experience and is on that account encountered in no experience—comes to nothing more than an empty entity of thought.

We are left, then, with nothing but nature, and it is within nature that the coherence and ordering of the world's events must be sought by us. Freedom, understood as independence of nature's laws, is indeed an emancipation from compulsion—but no less from the guiding thread of every rule. For it will not do to say that, in place of nature's laws, laws of freedom enter into the causality of the world's course; since, were the latter fixed by laws, it would be no freedom at all, but itself nothing else than nature. Nature, then, and transcendental freedom are distinguished as lawfulness from lawlessness, whereof the former does indeed burden the understanding with the difficulty of pursuing the descent of occurrences ever higher up the series of causes, since in them causality stands conditioned at every point, yet by way of compensation it holds out a thoroughgoing and lawlike unity of experience, whereas the delusion of freedom, while it holds out to the probing understanding a resting place amid the causal chain—conducting it toward an unconditioned causality that sets itself acting spontaneously—nonetheless, blind as it is in itself, tears loose the guiding thread of the rules on which alone a thoroughly connected experience rests.

Comment on the Third Antinomy.

I. Regarding the Thesis.

Far from exhausting the whole content of the psychological concept that bears this same name—a concept in large measure empirical—the transcendental idea of freedom covers only the part touching the absolute spontaneity of the action, which is the genuine ground of that action's imputability; and yet it remains the real rock of offense for philosophy, which meets with insuperable difficulties the moment it is to concede a kind of unconditioned causality of this sort. So in the matter of the will's freedom, whatever it is that has ever since kept speculative reason in such deep embarrassment is at bottom merely transcendental, and comes down solely to this: whether one must assume a power to commence of itself a series of successive things or states. In what way such a thing is possible is not something we are equally bound to be able to answer; for with causality by natural laws as well we must rest satisfied with cognizing a priori that a causality of the kind has to be presupposed, notwithstanding that the possibility—how, by way of one existence, the existence of another comes to be posited—escapes our comprehension entirely, so that on this point we are thrown back upon experience alone. To be sure, the way we have actually exhibited this necessity—that a series of appearances have a first beginning out of freedom—reaches only as far as is required to render an origin of the world intelligible, whereas all the states that ensue may be regarded as a sequence proceeding by mere natural laws. But since hereby the power to inaugurate a series in time wholly of itself stands after all demonstrated (even if not discerned), we are now at liberty as well to allow, right in the midst of the world's course, sundry series to begin of themselves as to their causality, and to endow the substances of these with a power of acting out of freedom. But here one should not let oneself be held back by a misconstrual—namely, that inasmuch as a successive series within the world admits only of a beginning that is first in a comparative sense (there being always some prior state of things in the world), no absolutely first beginning of such series could be possible in the course of the world. For our talk here concerns not a beginning absolutely first in the order of time, but one first in the order of causality. Should I at this moment (say) get up from my chair with complete freedom, and untouched by any determining compulsion from natural causes, then with this occurrence—and with its natural consequences running on to infinity—a brand-new series takes its start absolutely, notwithstanding that, temporally regarded, the occurrence is but the sequel to a series that went before. For this resolve and this act by no means lie within the train of merely natural effects, nor are they simply its prolongation; on the contrary, the determining natural causes leave off entirely, above them, in regard to this event—an event that succeeds those causes yet does not issue from them, and that consequently, though not in the order of time, must for all that, in the order of causality, be termed an utterly first beginning of a series of appearances.

How firmly reason needs to invoke, within the chain of natural causes, a first beginning grounded in freedom is borne in upon the eye with great clarity by this: that every philosopher of antiquity (the Epicurean school aside) felt driven, in accounting for the world's motions, to posit a first mover, i.e. a cause acting freely that first, and from itself, started this series of states. For from nature by itself they did not dare to render a first beginning intelligible.

II. Regarding the Antithesis.

The advocate of nature's omnipotence (transcendental physiocracy), set against the doctrine of freedom, would defend his proposition, over and against the latter's sophistical reasonings, after the following fashion. If you assume nothing mathematically first, with respect to time, in the world, then neither have you any need to look for something dynamically first, with respect to causality. Who charged you with thinking up a world-state that is first in the strict sense, and thereby an absolute commencement of the gradually unwinding series of appearances, and—merely to secure your fancy a point of rest—with imposing limits upon nature's boundlessness? The world's substances have always been there—or at any rate the unity of experience renders that assumption unavoidable—and so nothing stands in the way of granting further that the succession of their states, i.e. a running series of their changes, has likewise always obtained, whence no first beginning, be it mathematical or dynamical, would be admissible to seek. That an endless lineage of this sort should be possible—one lacking any first link with reference to which everything remaining is merely consequent—cannot, as to its very possibility, be brought to comprehension. But if it is on this ground that you would cast aside these enigmas of nature, you will see yourselves constrained to disown many a synthetic fundamental constitution (fundamental forces) that you can just as little make sense of, and even the bare possibility of alteration as such is bound to give you offense. For were it not that experience apprises you of its actuality, you would be forever unable to contrive a priori how a succession of being and non-being so unremitting could be possible.

Even granting, at the most, a transcendental power of freedom for the purpose of inaugurating the world's changes, this power would still have to lie, at the least, wholly beyond the world (albeit it stays ever a rash pretension to posit, past the entire compass of every possible intuition, some further object incapable of being given in any possible perception). But to invest the substances within the world itself with such a power can never be allowed, for in that case what one names nature—the interconnection of appearances that reciprocally and necessarily determine one another under universal laws—together with the criterion of empirical truth whereby experience is set apart from dreaming, would for the greater part evaporate. For alongside a power of freedom so lawless there is hardly any nature left to think, seeing that its laws would suffer ceaseless modification from the influences of that power, and the interplay of appearances—which, under nature alone, would run orderly and uniform—would be thrown thereby into confusion and disconnection.

The Antinomy of Pure Reason

Fourth Conflict of the Transcendental Ideas.

Thesis.

To the world there belongs something that, either as its part or as its cause, is an absolutely necessary being.

Proof.

The world of sense, being the whole of all appearances, likewise harbors within itself a series of alterations. For, lacking these, we should not so much as be given the representation of the time-series that serves as a condition for the possibility of the world of sense.⁵⁰ Every alteration, however, stands beneath a condition that goes before it in time and renders it necessary. Now, in respect of its existence, whatever is given as conditioned presupposes a complete series of conditions reaching up to the absolutely unconditioned, and this alone is absolutely necessary. Hence, should an alteration exist as its consequence, something absolutely necessary must exist as well. This necessary thing, though, belongs to the world of sense itself. For assume it to lie outside that world: the series of the world's alterations would then take its beginning from it, and yet this necessary cause would not itself belong to the world of sense. Yet this is impossible. For a beginning within a time-series can be fixed only by that which precedes it temporally, and so the highest condition for the beginning of a series of alterations must be present at the time in which that series did not yet exist (since a beginning is an existence preceded by a time throughout which the thing that begins was not yet there). Accordingly, the causality belonging to the necessary cause of these alterations — and thus the cause itself as well — pertains to time, and thereby to appearance (wherein alone time is possible, and that as its form); it therefore cannot be conceived in separation from the world of sense, that is, the sum total of all appearances. There is thus contained in the world itself something absolutely necessary (be it the entire world-series as such, or merely a portion of it).

Antithesis.

Nowhere does there exist an absolutely necessary being — neither within the world, nor beyond it as its cause.

Proof.

Assume that the world itself, or something within it, is a necessary being: then, in the series of its alterations, there would be present either a beginning that, being unconditionally necessary, would lack any cause — which runs counter to the dynamical law by which all appearances are determined in time — or else a series that, itself beginningless and, notwithstanding the contingency and conditionedness of each of its parts, is taken as a whole to be absolutely necessary and unconditioned; and this last is self-contradictory, since no multitude can have a necessary existence when not one of its parts possesses an existence necessary in its own right.

Assume, conversely, that there is an absolutely necessary world-cause outside the world: this, as the highest member in the series of causes of the world's alterations, would be what first inaugurates the existence of the latter along with their series.⁵¹ But then it too would have to commence acting, so that its causality would fall within time and, for that very reason, within the sum total of appearances — that is, within the world — with the result that it itself, the cause, would not lie outside the world after all, in contradiction to the presupposition. Accordingly, no absolutely necessary being exists anywhere — neither within the world nor beyond it (albeit bound to it in causal connection).

Remark on the Fourth Antinomy.

I. On the Thesis.

For the purpose of proving that a necessary being exists, my task here is to employ no argument other than the cosmological one, which ascends from the conditioned within appearance to the unconditioned within the concept, treating the latter as the condition necessarily required for the absolute totality of the series. Attempting the proof from the bare idea of a highest being among all beings whatsoever pertains to a different principle of reason, and one of that kind will accordingly need separate treatment.

Now the pure cosmological proof can demonstrate the existence of a necessary being in no other way than by leaving it simultaneously unsettled whether that being is the world as such or something distinct from it. For to make out the latter, one needs principles that no longer count as cosmological and that fail to advance along the series of appearances, but rather concepts of contingent beings as such (so far as these are weighed merely as objects of the understanding), together with a principle for linking such beings to a necessary being by means of concepts alone — all of which is the business of a transcendent philosophy, for which there is as yet no room here.

But once the proof has been launched cosmologically — by placing beneath it, as its ground, the series of appearances together with the regress internal to that series, and this in keeping with empirical causal laws — one cannot thereafter leap off from this and cross over to something that belongs in no way in the series as one of its members. For in precisely that same sense must a thing be regarded as a condition, wherein the relation of the conditioned to its own condition was taken up within the series — that series which was meant to lead onward, in continuous advance, to this highest condition. Now if this relation is a sensible one and falls within the possible empirical employment of the understanding, then the highest condition or cause can bring the regress to a close only by laws of sensibility — hence only as something belonging to the temporal series — and the necessary being has to be viewed as the highest member of the world-series.

All the same, the liberty has been taken of executing just such a leap (μετάβασις εἰς ἄλλο γένος). For from the alterations in the world one concluded to empirical contingency — that is, to their dependence upon empirically determining causes — and thereby arrived at a series of empirical conditions that mounts upward, which was, moreover, quite correct. But since no first beginning and no highest member could be found here, one abruptly quit the empirical concept of contingency and reached for the pure category, which then set going a merely intelligible series whose completeness rested upon there being an absolutely necessary cause — a cause that, now bound to no sensible conditions, was likewise released from the temporal condition of having itself to begin its causality. This procedure, however, is wholly illegitimate, as the following considerations make clear.

In the pure sense of the category, contingent is whatever admits of its contradictory opposite as possible. But from empirical contingency there is simply no inferring that intelligible one. In the case of what undergoes alteration, the opposite (of its state) is actual at some other time and therefore possible as well; and so this is not the contradictory opposite of the earlier state, which would demand that, in the very same time at which the earlier state obtained, its opposite could have stood in its place — something that can by no means be inferred from the alteration. A body that was moving = A passes into rest = non A. Now from the circumstance that upon this there ensues a state opposed to state A, nothing at all can be concluded to the effect that A's contradictory opposite is possible, and thus that A is something contingent; for that would demand that, at the very same time the motion occurred, rest could instead have taken its place. All we know, at this point, is that rest was actual in the ensuing time and therefore possible as well. Motion at one time, however, and rest at another are by no means contradictorily opposed to each other. The succession of opposed determinations, then — that is, alteration — in no way proves contingency by concepts of the pure understanding, and it is therefore likewise incapable of leading to a necessary being's existence by pure concepts of the understanding. Alteration establishes only empirical contingency — that is, the fact that, by the law of causality, the new state could not possibly have occurred of itself, absent a cause belonging to the preceding time. Such a cause — even granting that it be taken as absolutely necessary — must in this manner still be met with in time and reckoned to the series of appearances.

II. On the Antithesis.

Should one fancy that, in mounting upward through the series of appearances, one runs into difficulties telling against the existence of an absolutely necessary supreme cause, then these too must not be grounded upon bare concepts concerning the necessary existence of some thing in general — and hence must not be ontological — but must rather emerge out of the causal linkage to a series of appearances (so as to posit for that series a condition that is itself unconditioned), and must accordingly be inferred cosmologically and by empirical laws. It has, namely, to be shown that the ascent in the series of causes (within the world of sense) can never terminate in an empirically unconditioned condition, and that the cosmological argument — drawn from the contingency of the world's states as manifested in their alterations — comes out against admitting a first cause that absolutely inaugurates the series.

Yet a curious contrast comes to light in this antinomy: namely, that from precisely the same ground of proof by which the existence of an original being was concluded in the thesis, the non-being of that being is concluded in the antithesis, and with no less stringency. At the outset it ran: a necessary being exists, on the ground that the whole of past time embraces the series of all conditions and therewith the unconditioned (the necessary) as well. Now it runs: no necessary being exists, and for that very reason — because the whole of elapsed time embraces the series of all conditions (which one and all are consequently, in their turn, conditioned). The ground of this is as follows. The first argument attends solely to the absolute totality of the series of the conditions, of which each determines another in time, and thereby comes to possess something unconditioned and necessary. The second, by contrast, brings under review the contingency of all that stands determined within the time-series (since before each there lies a time throughout which the condition must, in its turn, be determined as itself conditioned), whereby every unconditioned and all absolute necessity drops away completely. Meanwhile, the manner of inference in each is thoroughly suited even to ordinary human reason, which not infrequently comes to be at odds with itself once it weighs its object from two distinct standpoints. Herr von Mairan considered the quarrel between two celebrated astronomers, which sprang from a similar difficulty over the choice of standpoint, a sufficiently curious phenomenon to make it the subject of a treatise of its own. The one reasoned thus: the moon revolves about its axis, for the reason that it perpetually presents the same face to the earth; the other: the moon does not revolve about its axis, and for that very reason, that it perpetually presents the same face to the earth. Both conclusions were sound, according to the standpoint one adopted from which one wished to observe the moon's motion.

Third Section. On the interest of reason in these its conflicts.

So now the whole dialectical game of the cosmological ideas lies before us, ideas that in no way allow a congruent object to be given them in any possible experience, indeed that do not even allow reason to think them in accord with universal laws of experience — laws that are, for all that, not arbitrarily contrived, but ones to which reason is of necessity led in the continuous progress of the empirical synthesis, whenever it wishes to release from every condition that which, by the rules of experience, can always be determined only conditionally, and to seize it in its unconditioned totality. These ratiocinating assertions are so many endeavors to resolve four natural and inescapable problems that reason poses, of which, accordingly, there can be exactly this many, no more and likewise no fewer, since there exist no further series of synthetic presuppositions that draw an a priori limit around the empirical synthesis.

We have presented the brilliant pretensions of a reason that widens its territory past every boundary of experience only in dry formulas that contain merely the ground of its rightful claims, and, as befits a transcendental philosophy, we have divested them of all that is empirical, even though the entire magnificence of reason's assertions can blaze forth only in conjunction with that very element. In this application, however, and in the steadily advancing enlargement of reason's use, as it sets out from the field of experiences and by degrees soars upward to these sublime ideas, philosophy manifests a dignity that, could it only make good its pretensions, would leave the worth of all other human science far beneath itself, inasmuch as it holds out the foundation for our greatest expectations and prospects regarding the final ends in which every exertion of reason must at last come together. The questions — whether the world possesses a beginning and some boundary to its extension in space; whether anywhere, and perhaps within my thinking self, there is an indivisible and indestructible unity, or nothing but what is divisible and transitory; whether in my actions I am free, or, like other beings, am led along the thread of nature and of destiny; and whether, in the end, a supreme world-cause exists, or whether instead the natural things and their order make up the ultimate object at which we must come to rest in all our reflections: these are questions to whose resolution the mathematician would happily surrender his whole science; for that science, after all, can furnish him no contentment with respect to the highest and most pressing ends of humanity. Even the proper dignity of mathematics (this pride of human reason) rests on the fact that, since it gives reason the guidance to gain insight into nature, in the large as much as in the small, in respect of its order and lawful regularity, and likewise in the admirable unity of the forces that move it, far beyond every expectation of a philosophy that builds upon ordinary experience, it thereby itself furnishes occasion and encouragement for that use of reason extended past all experience, and likewise stocks the worldly wisdom occupied therewith with the finest materials for lending support, so far as the character of the inquiry permits, to its research by way of appropriate intuitions.

Unfortunately for speculation (though perhaps fortunately for the practical vocation of the human being), reason, in the midst of its greatest expectations, finds itself so hemmed in by a press of grounds and counter-grounds that, since for the sake both of its honor and even of its safety it is not advisable to draw back and to look on with indifference at this quarrel as at a mere mock combat, still less flatly to command peace, because the object of the strife is one of keen interest, nothing further is left to it than to ponder the origin of this dissension of reason with itself: whether perhaps some mere misunderstanding may be at fault in it, upon whose clearing up the proud claims on either side would indeed perhaps drop away, but in their stead a lasting and untroubled reign of reason over understanding and the senses would take its start.

For the present we will still hold this thorough treatment in abeyance and beforehand take into account the following: toward which side we would most readily incline, were we by chance compelled to take a side. Since in this case we consult not the logical touchstone of truth but merely our own interest, such an inquiry, even though it decides nothing regarding the contested right of the two parts, will nevertheless prove useful in rendering intelligible why those taking part in this dispute have thrown in with the one side rather than the other, without any superior insight into the object having in fact been the reason for it, and useful, likewise, in explaining still other incidental matters, for example the zealous heat of the one party and the cool assertion of the other, why they gladly cheer their joyous applause to the one and are irreconcilably prejudiced beforehand against the other.

There is, however, something that in this preliminary assessment fixes the standpoint from which alone it can be undertaken with due thoroughness, and this is the comparison of the principles from which the two parts proceed. Among the assertions of the antithesis one notices a perfect uniformity in the manner of thinking and a complete unity of maxim, namely a principle of unmixed empiricism, not merely in explaining the appearances within the world, but also in resolving the transcendental ideas concerning the world-whole itself. The assertions of the thesis, on the other hand, place at the basis, over and above the empirical mode of explanation within the series of appearances, intellectual beginnings as well, and to that extent the maxim is not simple. But, taking my cue from its essential distinguishing mark, I will call it the dogmatism of pure reason.

On the side, then, of the dogmatism in the determination of the cosmological ideas of reason, or of the thesis, there shows itself:

First, a certain practical interest, in which everyone of good disposition, if he understands his own true advantage, gives a heartfelt assent. That the world had a beginning, that the self which thinks in me is of simple, and on that account imperishable, nature, that this same self is at once free in its voluntary actions and lifted above the constraint of nature, and that, in the end, the whole order of the things making up the world stems from an original being from which everything borrows its unity and purposive connection: these amount to just so many cornerstones for morality and for religion. The antithesis tears away from us every one of these supports, or at any rate appears to do so.

Second, a speculative interest of reason likewise makes itself felt on this side. For when the transcendental ideas are adopted and put to use in this fashion, one can grasp wholly a priori the entire chain of conditions and comprehend the derivation of the conditioned, by starting from the unconditioned; something the antithesis does not accomplish, and thereby recommends itself very badly, in that it can offer no answer to the question about the conditions of its synthesis that would not leave over, endlessly, an ever further asking. On its account, from any given beginning one has to climb to a yet higher one, every part points to a yet smaller part, each occurrence has above it still another occurrence serving as its cause, and the conditions of existence taken generally brace themselves ever again upon others, without ever gaining, in some self-subsisting thing as original being, an unconditioned footing and support.

Third, this side has, over and above this, the advantage of popularity, which surely makes up no small part of its recommendation. Ordinary understanding meets not the least difficulty in the ideas of the unconditioned beginning of all synthesis, since in any case it is more used to descending toward consequences than to climbing toward grounds, and in the concepts of the absolutely first (over whose possibility it does not brood) it possesses a comfort and, at the same time, a fixed point on which to fasten the guiding cord of its steps, whereas in the restless ascent from conditioned to condition, forever with one foot in the air, it can take no pleasure whatever.

On the side of empiricism in the determination of the cosmological ideas, or of the antithesis, there is to be found:

Firstly, no such practical interest springing from pure principles of reason as morality and religion carry along with them. Rather, mere empiricism seems to strip both of all force and influence. If no original being set apart from the world exists, if the world has no beginning and hence no author either, if our will is not free and the soul shares the same divisibility and corruptibility as matter: then the moral ideas and principles too forfeit all validity and topple along with the transcendental ideas that made up their theoretical prop.

By contrast, however, empiricism holds out to the speculative interest of reason advantages that are highly alluring and far exceed anything the dogmatic instructor in the ideas of reason might promise. On the former view, the understanding remains at every moment upon its own native ground, that is, the field consisting of nothing but possible experiences, whose laws it can track and by means of which it can extend, without end, its secure and graspable cognition. Here it can, and ought to, present the object both as it is in itself and in its relations for intuition, or else in concepts whose image can be set out clearly and distinctly in given, similar intuitions. Not only does it have no need to forsake this chain of the natural order so as to cling to ideas whose objects it does not know, because, being things of thought, they can never be given; rather, it is not even allowed to quit its work and, on the pretext that this has now been carried to its end, to cross over into the province of idealizing reason and to transcendent concepts, where it no longer has any need to observe and to inquire in keeping with the laws of nature, but only to think and to invent, assured that no facts of nature can refute it, since it is precisely not bound to their testimony, but may pass them by, or may even subordinate them to a higher authority, namely that of pure reason.

The empiricist will therefore never permit any epoch of nature to be taken as the absolutely first, or any limit of his outlook upon nature's compass to be viewed as the outermost, or a passage to be made from the objects of nature, which observation and mathematics enable him to resolve and to fix synthetically within intuition (the extended), to those that neither sense nor imagination can ever exhibit in concreto (the simple); nor will he grant that in nature itself one may place at the basis a faculty of acting independently of nature's laws (freedom) and thereby curtail for the understanding its work of tracking, along the guiding thread of necessary rules, the arising of appearances; nor, finally, will he allow that for anything the cause is to be sought outside of nature (original being), since we know nothing besides nature, it being the one thing that offers us objects and can instruct us about their laws.

To be sure, if the empirical philosopher, with his antithesis, has no other aim than to beat down the presumption and the overreach of a reason that misjudges its true vocation, which makes a great show of insight and knowledge just where insight and knowledge actually give out, and that means to pass off, as a furthering of the speculative interest, what one lets stand with respect to the practical interest, so as, where it suits its own comfort, to snap the thread of physical investigations and, on a pretense of extending cognition, to fasten that thread to transcendental ideas, through which one really cognizes only that one knows nothing; if, I say, the empiricist rested content with this, then his fundamental principle would amount to a maxim of restraint in its claims, of modesty in its assertions, and, at once, of the widest attainable enlargement of our understanding under the tutor genuinely appointed over us, namely experience. For under such circumstances we would not find ourselves robbed of intellectual presuppositions and belief for the benefit of our practical affairs; only these could not be allowed to appear under the title and the pomp of science and rational insight, because the properly speculative knowledge can nowhere light upon any object other than that of experience, and, once one crosses its boundary, the synthesis that ventures cognitions of a new sort, owing nothing to experience, is left without any substratum of intuition upon which it might be brought to bear.

But if, in this way, empiricism, with regard to the ideas, itself turns dogmatic (as for the most part it does) and brashly denies whatever stands above the reach of its intuiting cognitions, then it itself lapses into the fault of immodesty, which here is all the more to be censured because thereby an irreplaceable disadvantage is inflicted on the practical interest of reason.

Herein lies the opposition of Epicureanism⁵² to Platonism.

Both of them assert more than they know, yet in such a way that the former spurs on and advances knowledge, albeit to the detriment of the practical, while the latter does indeed put excellent principles for the practical into our hands, but on that very account, with regard to everything for which alone a speculative knowledge is granted us, allows reason to dwell on idealized explanations of natural appearances and, over this, to let physical research fall by the wayside.

As to the third moment that may be looked to in the preliminary choice between the two contending parts: it is quite remarkable that empiricism runs entirely counter to all popularity, however much one might have thought that ordinary understanding would eagerly seize upon a plan that undertakes to content it with nothing beyond experiential cognitions and the reason-governed coherence among them, rather than transcendental dogmatics forcing it to climb to concepts that far outreach the insight and the rational capacity of the heads most practiced in thinking. But precisely this is its motive. For it then finds itself in a condition in which not even the most learned man can presume any advantage over it. If it grasps little or nothing of the matter, then no one else can boast of grasping much more of it either, and although it cannot speak on this as academically as others, it can nonetheless ratiocinate about it beyond all measure, since it strolls about amid nothing but ideas, concerning which one is most eloquent precisely because one knows nothing of them; whereas over the investigation of nature it would have to grow wholly mute and confess its ignorance. Comfort, then, and vanity are already a powerful recommendation of these principles. And besides, although a philosopher finds it very hard to adopt anything as a principle when he cannot render an account of it to himself, or even to bring in concepts whose objective reality cannot be discerned, to ordinary understanding nothing is more familiar. It wants to have something with which it may confidently make a start. The trouble of grasping such a presupposition in its own right gives it no unease, because such a presupposition (given that it does not know what grasping means) never so much as enters its head, and it takes for known whatever, through frequent use, has grown habitual to it. In the end, however, all speculative interest fades away in it before the practical, and it fancies that it discerns and knows precisely what to assume or believe its anxieties or hopes drive it toward. Thus the empiricism of transcendentally idealizing reason is wholly stripped of all popularity, and however much that is prejudicial to the supreme practical principles it may harbor, there is nonetheless no cause whatever to fear that it will ever pass beyond the bounds of the school and gain, in the commonwealth at large, even a moderately notable standing or any favor with the great multitude.

Human reason is by its nature architectonic, that is, it views all cognitions as members of a possible system and therefore admits only such principles as at least do not make a cognition one has in view unfit to coexist with others within some system. The propositions of the antithesis, however, are of a sort that makes the completion of any structure of cognitions wholly impossible. On their showing, over any one state of the world there is always a still older one, in every part still further parts, again divisible, before every occurrence another that had likewise been produced in its turn from elsewhere, and, in existence generally, everything forever only conditioned, without any unconditioned and first existence being acknowledged. Since, therefore, the antithesis nowhere concedes a first and no beginning that might serve outright as the ground of the building, a finished edifice of cognition is, on presuppositions of this kind, wholly impossible. Hence the architectonic interest of reason (which calls for a rational unity that is not empirical but pure and a priori) brings with it a natural endorsement of the claims put forward by the thesis.

But could a human being renounce all interest and take the assertions of reason into consideration merely by the substance of their grounds, indifferent to all consequences, then such a person, granting that he knew of no way out of the press other than to profess himself to one or the other of the contending doctrines, would be in a ceaselessly wavering condition. On one day it would appear compelling to him that the human will is free; on the next, upon weighing the unbreakable chain of nature, he would judge freedom to be nothing more than a self-delusion, and hold that all things are simply nature. But once it came to deed and action, this game of merely speculative reason would dissolve like the phantom shapes of a dream, and he would settle his principles purely on the basis of the practical interest . Yet because it does become a reflective and inquiring being to devote certain seasons solely to the testing of its own reason, while therein casting off all partiality entirely and so imparting its remarks openly to others for their judgment, no one can be blamed, still less barred, for letting the propositions and counter-propositions step forward just as, frightened by no threat, they are able to defend themselves before jurors of their own estate (namely the estate of frail human beings).

Fourth Section. On the transcendental problems of pure reason, in so far as they absolutely must be capable of a solution.

To set out to solve every problem and to answer every question would amount to a brazen grandiloquence and to a conceit so unbridled that one would immediately strip oneself of all trust. And yet certain sciences are so constituted by their very nature that each question raised within them must, without qualification, admit of an answer drawn from what one already knows, since the answer is bound to issue from the same sources out of which the question issues, and where it is on no account permissible to fall back on inescapable ignorance—rather, a resolution may be insisted upon. In every conceivable case, what counts as right or wrong must, as a rule, be something we are able to know, since it touches our obligation, and where we cannot know, no obligation binds us either. When it comes to explaining the appearances of nature, by contrast, a great deal is bound to stay uncertain for us and more than one question insoluble, for what we know of nature falls far short, in many a case, of what we are called upon to explain. The question that now arises is this: whether, within transcendental philosophy, there is any question bearing on an object set before reason that this same pure reason proves unable to answer, and whether one is entitled to excuse oneself from giving it a conclusive answer by classing it—as something flatly uncertain (among all that lies within our power to cognize)—together with those matters of which we do indeed grasp enough to pose a question, while yet altogether lacking the means or the faculty to resolve it at any time.

My claim, then, is that transcendental philosophy holds, amid all speculative cognition, a peculiarity all its own: that not a single question touching on an object given to pure reason lies beyond solution for this very human reason, and that no appeal to an inescapable ignorance, or to some unfathomable depth in the task, can discharge us from the duty of answering it soundly and in full, seeing that the very concept enabling us to raise the question must without fail equip us as well to reply to it, inasmuch as the object is to be encountered nowhere apart from the concept itself (as happens with right and wrong).

Within transcendental philosophy, however, the only questions in whose case one may justly insist on a satisfactory answer touching the constitution of the object—without the philosopher being at liberty to slip away from it by pleading an impenetrable darkness—are the cosmological ones; and such questions can bear on nothing but cosmological ideas. For the object has to be something given in experience, and all that is asked is how far it matches an idea. Where the object is transcendental and therefore itself unknown—say, whether that something whose appearance (in our own case) is thinking, namely the soul, is a being simple in itself; whether there exists a cause of all things taken together that is absolutely necessary; and so forth—there we are to look, for our idea, to an object which we may grant is unknown to us and yet is not on that score impossible.⁵³ It is a feature belonging to the cosmological ideas, and to these alone, that they can take their object—together with the empirical synthesis that its concept demands—as already given; and the question issuing from them bears solely on the advance of this synthesis, in so far as that advance is to embrace absolute totality, a totality which is no longer anything empirical, since it can be furnished in no experience. Now since what is at issue here is merely a thing regarded as the object of a possible experience, and not as a thing existing in itself, the transcendent cosmological question can find its answer in nothing beyond the idea, for it has to do with no object taken in itself; and as regards possible experience, what is being asked after is not that which in concreto could be furnished in some experience, but that which resides in the idea, toward which the empirical synthesis is merely to draw nearer: and so it must admit of resolution from the idea by itself; for the idea is nothing but a product of reason, which accordingly cannot disown the accountability and load it onto the unknown object.

It is less remarkable than it may first appear that a science should be able, with respect to every question falling within its own compass (quaestiones domesticae), to insist upon and look forward to solutions that are one and all certain, even if for the time being they may perhaps still lie undiscovered. Apart from transcendental philosophy there remain two pure sciences of reason, the one merely speculative in content, the other practical: pure mathematics and pure morals. Has anyone ever heard it maintained that, owing as it were to a necessary ignorance of the conditions, it was pronounced uncertain what precise ratio the diameter holds to the circle, whether in rational or in irrational numbers? Since by the former it cannot be given congruently at all, while by the latter it has yet to be found, the verdict was that the impossibility of any such solution can at least be cognized with certainty, and of this Lambert furnished a proof. In the universal principles of morality there can be nothing uncertain, for the propositions are either wholly null and void of sense, or else must proceed simply from our concepts of reason. In the study of nature, on the other hand, conjectures are infinite in number, and for none of them may one ever look to attain certainty, because the appearances of nature are objects handed to us in a manner independent of our concepts, so that the key to them resides not in us and our pure thinking but beyond us, and precisely on that account cannot, in many cases, be tracked down, so that no reliable disclosure is to be looked for. I do not include here the questions of the transcendental analytic that concern the deduction of our pure cognition, since our present business is solely the certainty of judgments about objects, not the certainty about the origin of our concepts themselves.

We shall accordingly find no escape from the duty of at least a critical resolution of the rational questions placed before us by voicing laments over the cramped bounds of our reason and professing, with the air of a modest self-knowledge, that it surpasses our reason to settle whether the world has been from eternity or took a beginning; whether the space of the world is filled to infinity with beings or shut up within certain limits; whether anything at all in the world is simple, or whether everything must undergo division to infinity; whether there is a begetting and producing out of freedom, or whether everything is strung upon the chain of nature's order; and lastly whether some being exists that is utterly unconditioned and necessary in itself, or whether everything, in respect of its existence, is conditioned and hence dependent from without and contingent in itself. For every one of these questions concerns an object that admits of being given nowhere save in our thoughts—namely, the utterly unconditioned totality belonging to the synthesis of appearances. Should we prove unable to state and settle anything certain about it from our own concepts, we are not at liberty to lay the fault on the thing that hides itself from us; for no thing of that kind can be given to us at all (since outside our idea it is met with nowhere), and we must instead seek the cause in our idea itself—an idea that is a problem admitting of no resolution, and one to which we nonetheless obstinately suppose that an actual object answers. Were the dialectic residing within our very concept laid out with clarity, it would soon bring us to full certainty as to how a question of this sort ought to be judged on our part.

Against your plea of uncertainty regarding these problems one may set, to begin with, this question, which you are bound at the very least to answer plainly: from where do these ideas come to you, whose resolution here embroils you in such difficulty? Are they, perhaps, appearances that stand in need of explanation, and for which, following out these ideas, you have merely to search for the principles, or the rule, of their exposition? Grant that nature lay entirely disclosed before you, that nothing were concealed from your senses and from your awareness of all that is set before your intuition: even so, no single experience would let you cognize the object of your ideas in concreto (for beyond this complete intuition there would further be demanded a synthesis carried to completion, along with awareness of its absolute totality, which no empirical cognition can possibly yield); and thus your question can in no way be necessary for explaining any appearance that turns up, nor, so to speak, be assigned to you by the object itself. For the object can at no time present itself to you, since it can be given through no possible experience. Throughout every possible perception you stay hemmed in under conditions, be it in space or in time, and never reach anything unconditioned by which to settle whether this unconditioned should be looked for in the synthesis's absolute beginning or in an absolute totality of the series lacking any beginning whatever. The whole, though, taken in an empirical sense, is always merely comparative. As for the absolute whole of magnitude (the world-whole), of division, of descent, of the condition of existence as such—together with every question whether it is to be brought off through a finite synthesis or one to be prolonged to infinity—this lies wholly outside the concern of any possible experience. You could not, for example, account for the appearances of a body one jot better, nor even so much as otherwise, by supposing it to be composed of simple parts rather than, throughout, of composite ones; for neither a simple appearance nor, no less, an infinite composition can ever come before you. Appearances call for explanation only to the extent that the conditions for explaining them are furnished within perception; yet whatever may at any time be given in them, gathered up into a single absolute whole, is not itself a perception. Yet it is exactly this whole whose explanation the transcendental problems of reason call for.

Since, then, not even the solving of these problems can ever crop up within experience, you are in no position to maintain that it remains uncertain what should be attributed to the object on this point. For your object resides solely within your brain and admits of being given nowhere outside it; and so your only task is to reach agreement with yourself and to head off the amphiboly that would turn your idea into a purported representation of an object given empirically and therefore to be cognized in keeping with the laws of experience. The dogmatic solution, accordingly, is not so much uncertain as it is impossible. The critical one, on the other hand—which is capable of being wholly certain—regards the question not objectively at all, but in the light of the ground of the cognition on which it is founded.

Section 5. Skeptical representation of the cosmological questions through all four transcendental ideas.

We would happily abandon our insistence on having these questions settled dogmatically, could we but see beforehand this much: that no matter how the answer came out, it would do nothing but deepen our ignorance, tumbling us from one unintelligibility into the next, from one darkness into a darkness deeper still, and possibly even into outright contradictions. Where a question admits only of a yes or a no, the wiser course is to hold in reserve, for the time being, the supposed grounds on either side, and to weigh first of all what would actually be won should the verdict fall one way, and what should it fall the other. Should it emerge that either verdict yields pure vacuity of sense (nonsense), we then have solid warrant for turning a critical eye on the question itself, asking whether it may not rest upon some baseless assumption, trifling with an idea whose falsehood shows itself more plainly in the use one makes of it, and in what follows from it, than when the idea is entertained on its own. Herein lies the signal advantage of the skeptical way of handling those questions that pure reason addresses to pure reason, whereby a vast dogmatic tangle may be cleared away at slight cost, and replaced with a temperate critique that, working like a genuine purgative, will thoroughly flush out the delusion and its retinue, the craving to know everything.

Suppose, then, that of some cosmological idea I could discern at the outset the following: that whichever side of the unconditioned in the regressive synthesis of appearances it happened to take, it would in any event turn out, measured against every concept of the understanding, to be either too great or too small: I should then see that, given how this idea deals only with an object of experience meant to answer to a possible concept of the understanding, it must be wholly vacant and devoid of meaning, since no object squares with it, however I might contrive to fit one to it. And such is indeed the situation with every world-concept, which for this very reason drags reason, so long as it stays attached to them, into an inescapable antinomy. For only take

first, the world to have no beginning: then, set against your concept, it comes out too great; for that concept, resting as it does on a step-by-step regress, can never overtake the whole of an eternity already elapsed. Grant instead that it does have a beginning: then once more, for the concept your understanding forms in the requisite empirical regress, it proves too small. For a beginning still supposes some earlier time lying before it, and so is not yet unconditioned; the rule governing the empirical employment of the understanding lays on you the duty of inquiring after a yet higher temporal condition, and by that rule the world plainly falls out too small.

No differently does it go with the two competing answers to the question of the world's magnitude as regards space. For should it be infinite and without bound, then relative to any possible empirical concept it is too great. Is it finite and bounded, then you are within your rights to press further: what fixes that limit? Vacant space is no correlate of things subsisting in its own right, and can furnish no condition at which you might halt, and even less an empirical condition forming any part of a possible experience. (For of the utterly void, who could ever have any experience?) Yet the absolute totality of an empirical synthesis invariably demands that the unconditioned itself amount to a concept of experience. And so a bounded world proves, measured by your concept, too small.

Secondly: let every appearance in space (matter) be composed of infinitely many parts, and the regress of dividing them stands, for your concept, forever too great; but let the dividing of space come to rest at some one member of the series (the simple), and it stands, for the idea of the unconditioned, too small. For that member always leaves standing a further regress to the several parts it contains.

Thirdly: grant that whatever comes to pass in the world is nothing but consequence under the laws of nature, and the causality of any cause is itself, once again, an occurrence, one that makes your regress to a still higher cause—and thus the lengthening of the chain of conditions a parte priori—unending and unavoidable. Bare operative nature, then, outstrips your every concept in the synthesis of what befalls the world, being too great.

Opt here and there for happenings brought about spontaneously, and so for an origination out of freedom: at once the "why" dogs you under an inescapable law of nature, driving you past this point by the causal law of experience, and you find a totality of linkage of that kind to be too small for the empirical concept you cannot forgo.

Fourthly. Posit an utterly necessary being (whether the world at large, or some item within it, or the world's cause): you thereby lodge it in a time infinitely far removed from any moment you care to name, for otherwise it would hang upon some further, more ancient existence. But such an existence then lies beyond the reach of your empirical concept, indeed too great for you to arrive at by any prolongation of the regress whatever.

Should you hold, however, that everything comprised in the world (whether as conditioned or as its condition) is contingent: then any existence handed to you falls, for your concept, too small. For it forces you to go on casting about for some other existence upon which this one leans.

In each of these cases our claim has been that the idea of the world stands to the empirical regress, and therewith to any possible concept of the understanding, either as too great or else as too small. Why have we not put it the reverse way, saying: that in the first case the empirical concept is on every occasion too small for the idea, and in the second too great, so that the fault, so to speak, sticks to the empirical regress; rather than arraigning the cosmological idea for straying, by excess or by deficiency, from its aim, which is possible experience? Our reason ran thus. It is possible experience, and this alone, that can lend our concepts reality; failing that, a concept is nothing but an idea, bereft of truth and of any bearing on an object. The possible empirical concept therefore served as the measuring-rod against which the idea had to be assessed—whether it be a bare idea and creature of thought, or whether out in the world it does light upon its object. For we pronounce a thing too great or too small in comparison with something else only where it is posited purely for that other's sake and has to be tailored to it. One of the toys of the old dialectical schools was this puzzle: when a ball will not pass through a hole, how is one to put it—is the ball too big, or is the hole too small? Here it makes no difference which way you choose to phrase it; for you have no way of telling which of the pair exists for the sake of the other. You will not, on the other hand, declare the man too tall for his coat; you will say the coat is too short for the man.

We are thus led, at the very least, to a warranted suspicion: that the cosmological ideas—and with them every one of those subtly reasoned assertions pitted against each other—may rest at bottom on an empty, purely fancied concept of the manner in which the object of these ideas comes to be given us; and this suspicion is already enough to set us on the right scent, so that we may expose the sham that has misled us for so long.

Sixth Section. Transcendental idealism as the key to the solution of the cosmological dialectic.

In the transcendental aesthetic we established well enough: that whatever gets intuited in space or in time — and thus every object of an experience that is possible for us — amounts to nothing beyond appearances, that is, to mere representations which, taken just as they are represented, whether as extended beings or as series of alterations, possess outside our thoughts no existence grounded in itself. This tenet I term transcendental idealism.⁵⁴ The realist in the transcendental sense converts these modifications of our sensibility into self-subsistent things, and thereby turns mere representations into things in themselves.

It would be to wrong us were one to saddle us with that empirical idealism, so long and so widely decried, which, in granting the proper actuality of space, denies — or at the very least finds questionable — the existence of the extended beings lodged within it, and allows no adequately demonstrable difference between dream and truth on this head. Where the appearances of inner sense in time are concerned: with these, taken as actual things, it meets no difficulty; indeed, it goes so far as to claim that this inner experience, of itself and by itself alone, furnishes adequate proof of the actual existence of its object (in itself, along with the whole of this temporal determination).

Our transcendental idealism, conversely, grants this: that objects given to outer intuition are actual to just the degree that they are intuited in space, and that, within time, every alteration is as actual as inner sense presents it. For, space being already a form of the very intuition we term outer, and there being no empirical representation whatsoever apart from objects situated in it: we are both able and obliged to take extended beings within it to be actual; and matters stand no differently with time. And yet that space itself, this time along with it, and, together with the two of them, the whole of appearances, are of themselves no things, but purely and simply representations, and are wholly incapable of existing beyond our mind; indeed, even the inner, sensible intuition that our mind has of itself (as an object of consciousness), whose determination is presented by way of the succession of diverse states across time, is not the self proper, such as it exists in itself, nor is it the transcendental subject, but merely an appearance handed over to the sensibility of this being that remains unknown to us. That this inner appearance exists as a thing thus subsisting in itself is something that cannot be admitted, for its condition is time, and time can never serve as a determination of any thing considered in itself. Within space and within time, however, the empirical truth of appearances stands sufficiently secured, and is set well apart from any affinity with dream, so long as the two hang together, correctly and throughout, within one experience in accordance with empirical laws.

The objects of experience, then, are never given in them selves, but come to be given solely within experience, and apart from it they have no existence whatever. That there could be dwellers on the moon, though no human being has ever laid eyes on any, must of course be admitted, yet this signifies no more than this: that, in the possible onward march of experience, we might light upon them; for whatever hangs together, within a single context, with a perception according to the laws of the empirical advance is actual. They are, then, actual at the point where they enter into an empirical connection with my actual consciousness, though this by no means makes them actual in themselves, that is, outside this onward advance of experience.

Truly, nothing is handed to us save perception together with the empirical advance leading from it to further possible perceptions. For, taken in themselves, appearances — being mere representations — have their actuality nowhere but in perception, which is, in point of fact, nothing else than the actuality of an empirical representation, that is, of an appearance. To name an appearance a real thing in advance of perception signifies either that, in the course of experience, we are bound to light upon such a perception, or else it carries no significance at all. For one might well assert that it exists of itself, with no bearing on our senses and on possible experience, were the subject under discussion a thing in itself. But the subject under discussion is merely an appearance in space and in time, both of which amount to no determinations of things in themselves, but solely to determinations of our sensibility; and so whatever resides within them (appearances) is not, of itself, anything, but consists of mere representations that, unless they are given within us (in perception), are to be encountered simply nowhere.

The capacity for sensible intuition is, properly speaking, no more than a receptivity — a susceptibility to being affected, in a certain manner, by representations whose mutual relation constitutes a pure intuition of space and of time (these being one and all forms of our sensibility), and which, to the extent that within this relation (space and time) they admit of connection and determination according to the laws by which experience is made one, receive the name objects. What non-sensibly causes these representations stays altogether hidden from us, so that we are unable to intuit it as an object; for an object of that kind would have to be presented neither in space nor in time (which are but conditions of sensible representation), and without those conditions no intuition can so much as be thought by us. We may nevertheless assign to the merely intelligible cause of appearances at large the title of transcendental object, purely so as to have on hand something answering to sensibility taken as a receptivity. To this transcendental object we are free to assign the entire scope and interconnection of the perceptions possible for us and to declare: that, of itself, it stands given antecedently to all experience. The appearances, though, are, in conformity with it, given not of themselves but solely within this experience, since they are mere representations that stand for an actual object only in the guise of perceptions, namely when a given perception coheres with all the rest according to the rules by which experience is unified. One may accordingly put it thus: the actual things belonging to past time have their givenness in the transcendental object of experience; yet they count, for me, as objects — and as actual in bygone time — only so far as I picture to myself that a regressive series of possible perceptions (be it upon the guiding thread of history, or upon the traces of causes and their effects) leads, by empirical laws — the course of the world, in short — back to an elapsed stretch of time serving as the condition of the present time, a stretch that even then is pictured as actual only within the nexus of a possible experience and not of itself, so that every event that has run its course from unfathomable antiquity, before ever I existed, signifies nothing beyond the possibility of lengthening the chain of experience upward, from the perception now at hand, toward the conditions that fix it as regards time.

Should I, then, picture to myself the totality of existing objects of the senses across all time and all spaces at once: I am not thereby inserting them into the two ahead of experience; rather, such a picture is nothing else than the thought of a single possible experience taken in its absolute entirety. Within it, and nowhere besides, are those objects (which are nothing beyond mere representations) actually given. But to say that they exist ahead of all my experience amounts merely to saying that they are to be encountered in that portion of experience to which I, taking my start from perception, have first of all to press forward. The cause of the empirical conditions of this advance — hence upon which members, and likewise how far, I might light upon such in the regress — is transcendental, and for that reason bound to remain unknown to me. Yet it is not this cause that is at issue, but merely the rule governing the advance of experience, wherein the objects, that is to say appearances, come to be given to me. In its upshot, moreover, it comes to precisely the same thing: whether I say that, in the empirical progression through space, I might chance upon stars a hundredfold more remote than the outermost ones within my sight; or whether I say that such are perhaps to be met with somewhere in cosmic space, even though no human being has ever perceived them or ever shall; for even were they given as things in themselves, bearing no relation at all to possible experience as such, they remain, for me, nothing whatever — and hence no objects — save to the degree that they fall within the series of the empirical regress. It is only in a bearing of a wholly different sort — where these very appearances are to be pressed into service for the cosmological idea of an absolute whole, and where the question at stake accordingly overreaches the boundaries of possible experience — that it becomes of any moment to distinguish the manner in which one takes the actuality of such thought objects of the senses, this being needed to head off a treacherous delusion that cannot but arise out of a misreading of our own concepts of experience.

Section 7. Critical decision of the cosmological conflict of reason with itself.

The whole antinomy into which pure reason falls turns upon a single dialectical inference: if something conditioned is given, then so too is the entire series of the conditions on which it depends; now, the objects of sense are presented to us as conditioned; consequently, etc. Through this rational inference—whose major premise looks so natural and compelling—there arise, according to the different kinds of conditions (within the synthesis of appearances) so far as these make up a series, precisely as many cosmological ideas; and these ideas demand the absolute totality of such series, thereby throwing reason inevitably into discord with itself. Before we lay bare the deceptive character of this sophistical argument, however, we must first equip ourselves for the task by correcting and pinning down certain concepts that turn up within it.

First, this much is plain and beyond any doubt: that once the conditioned is given, we are thereby handed a regress through the series of all its conditions as our task; for the concept of the conditioned already entails as much, since by it a thing is referred back to a condition, and, should that condition itself be conditioned, to one still further removed, and thus onward through every member of the series. This proposition, accordingly, is analytic, and it rises above all dread of any transcendental critique. It amounts to a logical postulate of reason—to track by means of the understanding, and to prolong as far as one can, that linkage of a concept with its conditions which is already inherent in the concept as such.

Furthermore: supposing that both the conditioned and its condition are things in themselves, then, when the former has been given, the regress to the latter is not merely set as a task—rather, that latter is in fact co-given along with it; and, because this applies to each member of the series alike, the complete series of conditions, and with it the unconditioned too, is at once co-given—or, more precisely, is taken for granted the moment the conditioned (which only that series rendered possible) is given. Here the synthesis linking the conditioned to its condition is one performed by the mere understanding, which represents things as they are while paying no regard to whether, or how, we might arrive at cognizance of them. With appearances, by contrast—which, being nothing more than representations, are simply not given until I gain cognizance of them (i.e., until I arrive at the appearances themselves, since they amount to nothing beyond empirical cognizances)—I cannot assert in that same sense that, the conditioned being given, all the conditions belonging to it (as appearances) are given along with it; and I am therefore in no position whatever to conclude to the absolute totality of their series. For appearances, within the very apprehension of them, are in themselves nothing but an empirical synthesis (one carried out in space and in time), and for that reason they are given solely within it. Now it in no way follows that, given the conditioned (in appearance), the synthesis making up its empirical condition is co-given and presupposed thereby; on the contrary, such a synthesis occurs for the first time only within the regress, and never independently of it. What one may quite properly say in such a case, however, is that on this side a regress toward the conditions—that is, an ongoing empirical synthesis—is commanded or set as a task, and that conditions supplied by this regress can never run short.

This makes it plain that the major premise of the cosmological syllogism construes the conditioned in the transcendental sense proper to a pure category, while the minor premise construes it in the empirical sense of an understanding-concept brought to bear on mere appearances; and so the dialectical sleight lodged within it is the one known as Sophisma figurae dictionis. This deceit, however, is nothing artificially manufactured, but rather a wholly natural delusion of ordinary reason. For by means of it we take for granted (in the major premise) the conditions together with their series, sight unseen as it were, the instant something is presented as conditioned—this being merely the logical requirement that complete premises be posited for a given conclusion; and in the tie between the conditioned and its condition no temporal ordering shows up at all: the two are assumed, in themselves, to be given all at once. It is, moreover, just as natural (in the minor premise) to treat appearances as if they were things in themselves—objects, that is, delivered to the understanding on its own—exactly as was done in the major premise, seeing that I had set aside every condition of intuition, the sole conditions under which objects can be given to us. Yet in proceeding thus we had passed over a noteworthy distinction between these concepts. The joining of the conditioned to its condition, along with the whole series of those conditions (in the major premise), brought with it no restriction by time whatever and no notion of succession. The empirical synthesis, on the other hand—the series of conditions within appearance, the one subsumed under the minor premise—is of necessity successive, its members given only in temporal succession; and so I was unable, in this case, to presuppose the absolute totality of the synthesis and of the series it represents here in the way I could in the other, for there every member of the series stands given in itself (with no temporal condition attached), while here the members become available only by way of the successive regress, a regress that exists only insofar as one genuinely carries it through.

Now that a false step of this kind has been fastened upon the argument that both sides had jointly placed at the base (of the cosmological assertions), the two disputing parties may with justice be turned away as litigants who ground their demand on no valid title. Still, this does not so far settle their contest as to have proven them—both, or at least one of the pair—mistaken in the very thing asserted (in the conclusion), even granting that he could not rest it on solid grounds of proof. Indeed, nothing looks more evident than this: that where one party maintains the world had a beginning and the other maintains the world never began but reaches back through all eternity, surely one of the two has to be in the right. But if that holds, then—precisely because the evidence weighs the same on either hand—it still proves impossible ever to make out on which side the right resides; and the quarrel persists just as it did, even after the parties have been ordered to hold their peace before reason's court of law. No route is left, then, for bringing the dispute to a thorough close that will satisfy both sides, save this: that, given how elegantly each can demolish the other, they be brought in the end to see that their quarrel is about nothing at all, and that a certain transcendental illusion has conjured up for them an actuality in a place where none can be met with. It is precisely this way of laying to rest a quarrel admitting of no verdict that we now propose to follow.

The Eleatic Zeno, a dialectician of great subtlety, had already been rebuked in the strongest terms by Plato as a mischievous sophist, for this: that, in order to show off his art, he would prove one and the same thesis by means of specious arguments only to knock it down again, moments later, with others fully as strong. His claim was that God (though in his mouth this was presumably no more than the world) is neither the one nor the other of finite and infinite, is as little in motion as at rest, and stands neither in likeness nor in unlikeness to anything else whatsoever. It struck those who passed judgment on him here as though he had wished flatly to reject a pair of mutually contradictory claims—something plainly absurd. For my part, though, I do not see that the charge can justly be laid at his door. The first among these claims I shall shortly bring under closer scrutiny. As regards the others: supposing he took the term God to mean the universe, then he was surely bound to hold that it neither abides fixed in its location (at rest) nor shifts out of it (moves), for all locations lie within the universe alone, so that the universe has itself no location at all. If the totality of the world encloses within it all that there is, then, just so far, it bears neither resemblance nor its opposite to any other thing, since beyond it lies no other thing against which it might be measured. Whenever two mutually opposing judgments rest on a condition that cannot be granted, then, despite the conflict between them (which for all that is no real contradiction), the two collapse together, since there collapses the very condition on which alone either proposition was meant to stand.

Should someone declare that every body either has a good smell or has no good smell, a third possibility comes into play—namely, that it gives off no smell whatever (has no scent)—and thus the two opposing statements may both turn out false. Were I instead to say that it is either sweet-smelling or else not sweet-smelling (vel suaveolens vel non suaveolens), the two judgments would then stand in contradictory opposition, and only the former is false, while its contradictory counterpart—that some bodies are not sweet-smelling—takes in as well those bodies which give off no smell at all. In the earlier contrast (per disparata) the accidental condition belonging to the concept of bodies (their odor) stayed in force alongside the opposing judgment, and so went uncancelled by it, which is why that opposing judgment was not the contradictory counterpart of the first.

Suppose, then, that I assert the world to be, as regards space, either infinite or not infinite (non est infinitus); in that event, if the first statement is false, its contradictory opposite—that the world is not infinite—has to be true. By this I should be cancelling merely an infinite world while setting up no other in its place, no finite one, that is. If, however, the claim went: the world is either infinite or else finite (non-infinite), then the pair of them might both be false. For then I am looking upon the world as something fixed in itself as to its magnitude, inasmuch as, within the opposition, I do more than cancel infinity (and with it, it may be, the world's entire independent existence): I attach to the world a determination, treating it as a thing real in its own right—and this too may well be false, in case the world is not a thing in itself in any sense, and hence is not given, as to magnitude, either as infinite or as finite. Let me be permitted to name an opposition of this sort the dialectical kind, and the opposition of contradiction the analytic opposition. And so, of two judgments opposed in the dialectical manner, both may be false—just because the one, rather than simply contradicting its fellow, asserts something over and above what contradiction calls for.

Take the two propositions—that the world is infinite as to magnitude, and that the world is finite as to its magnitude—and treat them as contradictory opposites: one then supposes the world (the whole series of appearances) to be a thing existing in itself. For it goes on being just that, no matter whether it is the infinite or the finite regress within the series of its appearances that I cancel. Should I, on the other hand, strike out this presupposition—this transcendental illusion—and refuse the world any status as a thing in itself, the contradictory clash of the two claims is thereby transformed into one that is merely dialectical; and since the world enjoys no existence in itself whatever (apart from the regressive series of my representations), it exists as a whole neither infinite in itself nor finite in itself. One meets with it solely in the empirical regress that runs through the series of appearances; taken on its own, it is nowhere to be found. And so, this series being at all times conditioned, it is never given in its entirety; the world, accordingly, forms no unconditioned whole, and thus has no existence as a whole of that kind—whether its magnitude be infinite or finite.

Whatever has here been said regarding the first of the cosmological ideas—that is, the absolute totality of magnitude within appearance—applies equally to all the others. The series of conditions can be met with only in the regressive synthesis as such, and not on its own in the appearance, as though the latter were a self-subsistent thing given ahead of all regress. I shall therefore have to say, likewise, that the number of parts within any given appearance is, in itself, neither finite nor infinite—for an appearance is not anything self-subsistent, and its parts first come to be given by, and in the course of, the regress of the decomposing synthesis, a regress never delivered as flatly complete, be it finite or infinite. Precisely the same is true of the series of causes stacked one upon another, or of conditioned existence reaching up toward an existence unconditionally necessary, which can at no point be taken, as to its totality, for something either finite or infinite in itself; for as a series of subordinated representations it has its being only in the dynamical regress, whereas before that regress, as a self-standing series of things in themselves, it is incapable of existing at all.

Thus, then, is the antinomy of pure reason laid to rest in respect of its cosmological ideas—by the demonstration that it is nothing but dialectical, a clash produced by illusion, arising because the idea of absolute totality (valid only as a condition of things in themselves) has been carried over to appearances, which have their existence merely in representation and, when they form a series, in the successive regress, but which apart from this have no existence whatever. Turned around, however, this antinomy can also be put to a real use—critical and doctrinal in kind, though certainly not dogmatic: it lets us establish, by an indirect route, the transcendental ideality of appearances, for anyone who might find the direct demonstration in the transcendental aesthetic insufficient. That demonstration would take the shape of the following dilemma. Were the world a whole subsisting in itself, it would have to be either finite or else infinite. But the one option and the other are alike false (by the arguments set out above, those of the antithesis in the first case and of the thesis in the second). It is therefore likewise false that the world (the totality of all appearances taken together) constitutes a whole that subsists in itself. And from this it follows, in turn, that appearances as such amount to nothing beyond our representations—which is exactly the point we were making in speaking of their transcendental ideality.

This observation carries weight. It shows us that the foregoing proofs of the fourfold antinomy were no empty conjuring-tricks but soundly grounded—on the supposition, that is, that appearances, or a world of sense taking them all up within it, were things in themselves. The clash among the propositions derived from that supposition, however, discloses that a falsity is lodged in it, and in this way brings us to uncover the genuine character of things considered as objects of the senses. The transcendental dialectic, then, offers no aid whatever to skepticism, though it does aid the skeptical method, which may cite it as a specimen of its great value, once one allows reason's arguments to confront one another in their utmost freedom—arguments that, even if in the end they fail to deliver what was being sought, will yet on every occasion yield something useful, something that serves to set our judgments right.

Section 8. Regulative principle of pure reason in respect of the cosmological ideas.

Since, by the cosmological principle of totality, no greatest member of the conditions ranged in series within a sensible world—taken as a thing existing in its own right—is ever given, but can at most be set as a task as we regress through them: the principle of pure reason under discussion, its sense once rectified in this manner, still keeps its full legitimacy—not, to be sure, as an axiom bidding us conceive the totality in the object as actual, but as a problem posed to the understanding, hence to the subject, requiring it to set going and pursue, answerably to the completeness lodged in the idea, the regress through the conditions leading up to a given conditioned.

For within sensibility—that is, in space and in time—each condition we can reach while expounding appearances that are given proves in turn to be itself conditioned: for such appearances are no self-subsistent objects wherein the wholly unconditioned might conceivably have its place, but are nothing more than empirical representations, which have invariably to locate their condition in intuition, this condition fixing their place in space or in time. Properly speaking, then, the principle of reason amounts to nothing but a rule that enjoins, across the conditions belonging in series to given appearances, a regress which is at no point allowed to come to rest upon anything utterly unconditioned. It is accordingly no principle governing how experience is possible, nor how objects of the senses come to be cognized empirically, and so it is no principle of the understanding, since any experience stays shut within the limits set for it (in keeping with the intuition that is given); neither is it a constitutive principle of reason for stretching the concept of the sensible world past every experience that could be had: it is, rather, a principle for pressing experience onward and widening it as far as ever it will go, one under which no boundary met with empirically need count as a boundary that is absolute—in short, a principle of reason that as a rule lays down what we are to do in the regress, while it does not anticipate whatever may, in the object itself, stand given in advance of any regress at all. Hence I call it a regulative principle of reason—whereas the principle asserting an absolute totality of the conditions in their series, on the footing that it is given in itself within the object (that is, within the appearances), would come out as a constitutive cosmological principle, and it is exactly this drawing of a line that lets me expose the emptiness of such a principle, so as to head off what otherwise happens without fail (by way of transcendental subreption): the crediting of an idea, whose office is merely to serve as a rule, with objective reality of its own.

Now to pin down aright what this rule of pure reason means, one should observe at the outset that it is in no position to tell us what the object may be, but only in what manner the empirical regress ought to be set going, if we are to reach a complete concept of that object. For were the first of these the case, the rule would turn into a constitutive principle, and a thing of that sort can never issue from pure reason. One can therefore not in the least intend, by means of it, to pronounce the conditions that lead up to a given conditioned to be, taken by themselves, either finite or endless in their series; for so doing would let a bare idea of absolute totality, fashioned wholly out of itself, think an object that no experience can ever supply, since a run of appearances would thereby be endowed with an objective reality owing nothing to the empirical synthesis. All the idea of reason does, then, is lay down for the regressive synthesis running through the conditions a rule whereby that synthesis moves on from the conditioned, passing through every condition subordinate to another, toward the unconditioned—though the latter is at no time attained. For nowhere in experience does the strictly unconditioned come to be met with.

With this aim in view, the first thing is to fix with precision what the synthesis of a series comes to, given that such a synthesis is never brought to completion. For this end people ordinarily fall back on a pair of expressions supposed to mark off something here, though no one is really able to state on what the marking-off rests. Among mathematicians one hears exclusively of a progressus in infinitum. Those who inquire into concepts—the philosophers—would, in that phrase's stead, admit as valid only the term progressus in indefinitum. Rather than linger over weighing the misgiving that counseled the latter to draw such a line, or over whether the drawing of it proves serviceable or barren, I shall undertake to settle exactly what these concepts amount to as regards the end I have in view.

It is quite proper to say of a straight line that one may prolong it endlessly, and in this instance telling apart an infinite advance and one reaching indeterminably far (progressus in indefinitum) would amount to a hollow piece of hairsplitting. For granted that, when the direction runs: carry a line further, it does read more accurately to append in indefinitum rather than in infinitum—the first amounting to no more than: lengthen it as far as you care to, whereas the second says: you must never leave off lengthening it (and that is just not what is meant here)—still, so long as the discussion turns solely on what can be done, the first expression hits the mark exactly; for you are able to keep on enlarging the line without any end. And matters stand the same way in every case where the talk concerns merely the progressus—the passing onward, that is, from what conditions to what is conditioned; among appearances this possible passage runs on to infinity. Starting from a couple who are parents, you may proceed endlessly downward along the line of begetting and may perfectly well suppose that in the world it really does run on in that way. For at this point reason has no call for any absolute totality of the series, seeing that it does not lay such totality down beforehand as a condition, as though it were handed over (datum), but only as a further conditioned item, one that is merely such as can be supplied (dabile) and gets appended without any end.

The task wears an altogether different look when the question is this: how far does the regress reach that climbs from the conditioned already given up to its conditions taken in series; may I pronounce it a going-back into the infinite, or only a going-back that stretches indeterminably far (in indefinitum); and may I therefore, beginning with people now alive, mount upward without end through the line of their forebears, or is all that can be said this: that however far back my steps have carried me, at no point does an empirical ground turn up for treating the line as limited somewhere, so that I stand both entitled and bound to go on hunting, beyond each of the earliest fathers, for a progenitor of his—yet without being entitled to take one for granted.

My contention, then, is this: once the whole has been furnished in empirical intuition, the regress across the inner conditions ranged within it runs on to infinity. But where merely a single link of the series is on hand, one from which the regress toward absolute totality has yet to get under way: there occurs nothing beyond a going-back into indeterminate breadth (in indefinitum). So of the dividing of a portion of matter (a body) presented within its own bounds one has to say: it goes on to infinity. For this matter lies before us entire, and hence, together with each of the parts it can have, is furnished in empirical intuition. Since, now, what conditions this whole is a part of it, and what conditions that part is again a part lying within the part, and so forth, while throughout this regress of taking-apart no unconditioned—that is, indivisible—link of these serial conditions is ever come upon, there is not merely nowhere any empirical warrant for halting the division; rather, the still further links yielded by the division to be carried on are themselves, in advance of that continued dividing, given empirically—which is to say, the dividing proceeds to infinity. The line of forebears belonging to some particular person, by contrast, is nowhere within a possible experience laid out in its absolute totality; and yet the regress does climb from any link of this begetting to a higher one, so that we light upon no empirical bound that would set out some link as unconditioned in the strict sense. Since, however, the links that might here supply the condition do not, ahead of the regress, already lie within the empirical intuition of the whole: this regress does not run to infinity (as the dividing of what is given does), but into an indeterminable breadth in the hunt for additional links to append to those given, which in their turn are always themselves given only as conditioned.

In neither of the two cases—the regressus in infinitum no more than the in indefinitum—does one look upon the conditions in their series as given in the object as infinite. What we have here are not things existing in their own right but simply appearances, which, as one another's conditions, get furnished nowhere except in the regress itself. The question, accordingly, is no longer how large these serial conditions are in their own right, whether finite or infinite—for in their own right they are nothing at all—but rather how we go about the empirical regress and how far we ought to press it on. And on this head a considerable difference shows itself as regards the rule governing such advance. Where the whole has been supplied empirically, it is possible to make one's way back into the infinite through the inner conditions ranged within it. But where that whole is not supplied, and is instead to be furnished only through an empirical regress, all I can say is: it stays possible without end to move on to conditions higher still in the series. In the earlier case my statement could run: there stand present, empirically furnished, always more links than I ever get to by the regress (the taking-apart); in the second, however: within the regress I can push on yet further still, for no link is furnished empirically as unconditioned in the strict sense, and so a higher link is left standing as always possible, and with it the demand for that link as something required. There it was needful to come upon more links of the series, whereas here it is always needful to ask after more of them, since no experience sets an absolute bound. For either you possess no perception that draws a flat limit around your empirical regress—in which case you are not to hold that regress finished—or you do possess a perception of the sort that bounds your series, and then it cannot rank as one of the members already traversed (since what does the bounding has to be kept apart from what gets bounded by it), so that you are obliged to prosecute your regress onward to this condition as well, and thus without cease.

The section that comes next will, by putting these observations to use, cast upon them the light that is their due.

Ninth Section. On the empirical use of the regulative principle of reason, in respect of all cosmological ideas.

Since, as we have shown on several occasions, there is no transcendental use, neither of the understanding's pure concepts nor of reason's concepts; since the absolute totality of the series of the conditions in the sensible world rests solely upon a transcendental use of reason, which requires this unconditioned completeness of what it presupposes as a thing in itself, yet the sensible world contains no such thing: the discussion can accordingly no longer concern the absolute magnitude of the series within it, whether these be limited or in themselves unlimited, but only how far, in the empirical regress, we are to trace experience back to its conditions, so that we come to rest, as reason's rule prescribes, at no answer to its questions save the one befitting the object.

Thus what remains to us alone is the validity of reason's principle, taken as a rule governing the continuation and extent of any possible experience, once its invalidity as a constitutive principle of the appearances, taken in themselves, has been sufficiently demonstrated. Moreover, if we can set that validity beyond doubt before our eyes, the conflict of reason with itself is brought entirely to an end, since not only is the illusion that had set it at variance with itself removed through critical resolution, but in its place the sense in which reason accords with itself — and whose misinterpretation alone occasioned the conflict — is opened up, and a principle that was otherwise dialectical is transformed into a doctrinal one. Indeed, if this principle can be vindicated in its subjective significance — namely, to determine the understanding's greatest possible use in experience in a way conformable to that experience's objects — then it amounts to just as much as if, in the manner of an axiom (which, from pure reason, is impossible), it determined the objects in themselves a priori; for even the latter could have no greater influence, with respect to the objects of experience, upon the extension and correction of our cognition than by proving itself active in the most extensive empirical use of our understanding.