Appendix

SINCE all the ways heretofore taken have failed to attain the goal, and since without a preceding critique of pure reason it is not likely ever to be attained, the present essay now before the public has a fair title to an accurate and careful investigation, except it be thought more advisable to give up all pretensions to metaphysics, to which, if men but would consistently adhere to their purpose, no objection can be made.

All previous approaches have failed to reach the goal. Without first examining pure reason critically, it is unlikely that the goal will ever be reached. For these reasons, the present essay deserves a thorough and careful examination. The only alternative is to give up all claims to metaphysics. There can be no objection to that choice, if people consistently stick to it.

If we take the course of things as it is, not as it ought to be, there are two sorts of judgments: (1) one a judgment which precedes investigation (in our case one in which the reader from his own metaphysics pronounces judgment on the Critique of Pure Reason which was intended to discuss the very possibility of metaphysics); (2) the other a judgment subsequent to investigation. In the latter the reader is enabled to waive for awhile the consequences of the critical researches that may be repugnant to his formerly adopted metaphysics, and first examines the grounds whence those consequences are derived. If what common metaphysics propounds were demonstrably certain, as for instance the theorems of geometry, the former way of judging would hold good. For if the consequences of certain principles are repugnant to established truths, these principles are false and without further inquiry to be repudiated. But if metaphysics does not possess a stock of indisputably certain (synthetical) propositions, and should it even be the case that there are a number of them, which, though among the most specious, are by their consequences in mutual collision, and if no sure criterion of the truth of peculiarly metaphysical (synthetical) propositions is to be met with in it, then the former way of judging is not admissible, but the investigation of the principles of the critique must precede all judgments as to its value.

If we consider how things are, rather than how they ought to be, there are two kinds of judgment: (1) judgment before investigation and (2) judgment after investigation. In our case, the first occurs when a reader judges the Critique of Pure Reason according to his own metaphysics. Yet the Critique was intended to examine whether metaphysics is possible at all. In the second kind of judgment, the reader can temporarily set aside those conclusions of the critical inquiry that conflict with his previously accepted metaphysics. He first examines the grounds from which those conclusions follow. If the claims of ordinary metaphysics were demonstrably certain, like the theorems of geometry, the first way of judging would be valid. For if the consequences of certain principles conflict with established truths, those principles are false. They should be rejected without further inquiry. But metaphysics may lack a body of indisputably certain synthetic propositions. It may even contain a number of propositions whose consequences conflict with one another, though the propositions seem among the most convincing. And it may offer no reliable test for the truth of specifically metaphysical synthetic propositions. If so, the first way of judging is not acceptable. We must examine the principles of the critique before judging its value.

ON A SPECIMEN OF A JUDGMENT OF THE CRITIQUE PRIOR TO ITS EXAMINATION.

AN EXAMPLE OF A JUDGMENT OF THE CRITIQUE BEFORE EXAMINING IT.

This judgment is to be found in the Göttingischen gelehrten Anzeigen, in the supplement to the third division, of January 19, 1782, pages 40 et seq.

This judgment appears in the Göttingischen gelehrten Anzeigen, in the supplement to the third division, dated January 19, 1782, on page 40 and the following pages.

When an author who is familiar with the subject of his work and endeavors to present his independent reflexions in its elaboration, falls into the hands of a reviewer who, in his turn, is keen enough to discern the points on which the worth or worthlessness of the book rests, who does not cling to words, but goes to the heart of the subject, sifting and testing more than the mere principles which the author takes as his point of departure, the severity of the judgment may indeed displease the latter, but the public does not care, as it gains thereby; and the author himself may be contented, as an opportunity of correcting or explaining his positions is afforded to him at an early date by the examination of a competent judge, in such a manner, that if he believes himself fundamentally right, he can remove in time any stone of offence that might hurt the success of his work.

Suppose an author knows the subject of his work and tries to develop his own independent reflections on it. Suppose, too, that his book falls into the hands of a reviewer keen enough to see what determines its worth. The reviewer does not cling to words, but gets to the heart of the subject. He examines and tests more than the principles from which the author starts. A harsh judgment may displease the author, but the public does not care, because it benefits. The author himself may also be content, because a competent judge's examination gives him an early chance to correct or explain his positions. If he believes he is fundamentally right, he can remove any obstacles to his work's success before they do harm.

I find myself, with my reviewer, in quite another position. He seems not to see at all the real matter of the investigation with which (successfully or unsuccessfully) I have been occupied. It is either impatience at thinking out a lengthy work, or vexation at a threatened reform of a science in which he believed he had brought everything to perfection long ago, or, what I am unwilling to imagine, real narrowmindedness, that prevents him from ever carrying his thoughts beyond his school-metaphysics. In short, he passes impatiently in review a long series of propositions, by which, without knowing their premises, we can think nothing, intersperses here and there his censure, the reason of which the reader understands just as little as the propositions against which it is directed; and hence [his report] can neither serve the public nor damage me, in the judgment of experts. I should, for these reasons, have passed over this judgment altogether, were it not that it may afford me occasion for some explanations which may in some cases save the readers of these Prolegomena from a misconception.

My reviewer and I are in quite a different position. He seems not to see the real issue I have been investigating, whether successfully or unsuccessfully. Perhaps he is too impatient to think through a lengthy work. Or perhaps he resents a proposed reform of a science he believed he had perfected long ago. Or perhaps, though I am unwilling to believe it, he is genuinely narrow-minded. One of these things prevents him from ever thinking beyond the metaphysics taught in his school. In short, he impatiently runs through a long series of propositions. Without knowing their premises, we can make nothing of them. Here and there he adds his criticism. The reader understands the reasons for his criticism no better than the propositions he criticizes. So his report can neither serve the public nor damage me, in the judgment of experts. For these reasons, I would have ignored his judgment altogether. But it may give me an opportunity to offer some explanations. These may, in some cases, save readers of these Prolegomena from a misunderstanding.

In order to take a position from which my reviewer could most easily set the whole work in a most unfavorable light, without venturing to trouble himself with any special investigation, he begins and ends by saying:

My reviewer wants to put the whole work in the worst possible light without bothering to investigate any part of it. To do this as easily as possible, he begins and ends by saying:

"This work is a system of transcendent (or, as he translates it, of higher) Idealism."⁴⁵

"This work is a system of transcendent Idealism (or, as he translates it, higher Idealism)."⁴⁵

A glance at this line soon showed me the sort of criticism that I had to expect, much as though the reviewer were one who had never seen or heard of geometry, having found a Euclid, and coming upon various figures in turning over its leaves, were to say, on being asked his opinion of it: "The work is a text-book of drawing; the author introduces a peculiar terminology, in order to give dark, incomprehensible directions, which in the end teach nothing more than what every one can effect by a fair natural accuracy of eye, etc."

A glance at this line soon showed me what kind of criticism to expect. It was as if the reviewer had never seen or heard of geometry, but had found a Euclid. On leafing through it, he came across various figures. When asked for his opinion of the book, he might say: "This work is a drawing textbook. The author uses peculiar terms to give obscure, incomprehensible instructions. In the end, these teach nothing more than anyone can do with a reasonably accurate eye, etc."

Let us see, in the meantime, what sort of an idealism it is that goes through my whole work, although it does not by a long way constitute the soul of the system.

For now, let us consider what kind of idealism runs through my whole work. Although it is far from being the heart of my system, idealism runs through the whole work.

The dictum of all genuine idealists from the Eleatic school to Bishop Berkeley, is contained in this formula: "All cognition through the senses and experience is nothing but sheer illusion, and only, in the ideas of the pure understanding and reason there is truth."

All genuine idealists, from the Eleatic school to Bishop Berkeley, hold this view: "All knowledge gained through the senses and experience is nothing but illusion. Truth lies only in the ideas of pure understanding and reason."

The principle that throughout dominates and determines my Idealism, is on the contrary: "All cognition of things merely from pure understanding or pure reason is nothing but sheer illusion, and only in experience is there truth."

On the contrary, this principle guides and defines my Idealism throughout: "All knowledge of things based only on pure understanding or pure reason is sheer illusion. Truth is found only in experience."

But this is directly contrary to idealism proper. How came I then to use this expression for quite an opposite purpose, and how came my reviewer to see it everywhere?

But this is directly opposed to idealism itself. So why did I use the term for the opposite purpose? And why did my reviewer see idealism everywhere?

The solution of this difficulty rests on something that could have been very easily understood from the general bearing of the work, if the reader had only desired to do so. Space and time, together with all that they contain, are not things nor qualities in themselves, but belong merely to the appearances of the latter: up to this point I am one in confession with the above idealists. But these, and amongst them more particularly Berkeley, regarded space as a mere empirical presentation that, like the phenomenon it contains, is only known to us by means of experience or perception, together with its determinations. I, on the contrary, prove in the first place, that space (and also time, which Berkeley did not consider) and all its determinations a priori, can be cognised by us, because, no less than time, it inheres in our sensibility as a pure form before all perception or experience and makes all intuition of the same, and therefore all its phenomena, possible. It follows from this, that as truth rests on universal and necessary laws as its criteria, experience, according to Berkeley, can have no criteria of truth, because its phenomena (according to him) have nothing a priori at their foundation; whence it follows, that they are nothing but sheer illusion; whereas with us, space and time (in conjunction with the pure conceptions of the understanding) prescribe their law to all possible experience a priori, and at the same time afford the certain criterion for distinguishing truth from illusion therein.⁴⁶

The solution to this difficulty could easily have been understood from the general direction of the work, if the reader had wanted to understand it. Space and time, together with everything they contain, are not things or qualities in themselves. They belong only to the appearances of things and qualities. Up to this point, I agree with the idealists mentioned above. But these idealists, especially Berkeley, regarded space as a merely empirical representation. Like the phenomena it contains, space and its features are known to us only through experience or perception. By contrast, I first prove that we can know space and all its features a priori. The same is true of time, which Berkeley did not consider. This is because space, like time, belongs to our sensibility as a pure form before any perception or experience. It makes possible all intuition of experience, and therefore all the phenomena of experience. Truth rests on universal and necessary laws as its criteria. It follows that, according to Berkeley, experience can have no criteria of truth. For according to him, its phenomena have nothing a priori as their foundation. It follows that the phenomena are nothing but sheer illusion. In my account, by contrast, space and time, together with the pure concepts of the understanding, prescribe their law a priori to all possible experience. They also provide a certain criterion for distinguishing truth from illusion in experience.⁴⁶

My so-called (properly critical) Idealism is of quite a special character, in that it subverts the ordinary idealism, and that through it all cognition a priori, even that of geometry, first receives objective reality, which, without my demonstrated ideality of space and time, could not be maintained by the most zealous realists. This being the state of the case, I could have wished, in order to avoid all misunderstanding, to have named this conception of mine otherwise, but to alter it altogether was impossible. It may be permitted me however, in future, as has been above intimated, to term it the formal, or better still, the critical Idealism, to distinguish it from the dogmatic Idealism of Berkeley, and from the sceptical Idealism of Descartes.

My so-called Idealism, properly called critical Idealism, is quite distinctive because it overturns ordinary idealism. Through it, all a priori knowledge, including geometry, gains objective reality for the first time. Without my demonstration that space and time are ideal, even the most zealous realists could not uphold that objective reality. Given this, I would have preferred another name for my conception, to avoid any misunderstanding. But I could not change the name altogether. As I suggested above, however, I hope I may call it formal Idealism, or better still, critical Idealism. This distinguishes it from Berkeley's dogmatic Idealism and Descartes's skeptical Idealism.

Beyond this, I find nothing further remarkable in the judgment of my book. The reviewer criticises here and there, makes sweeping criticisms, a mode prudently chosen, since it does not betray one's own knowledge or ignorance; a single thorough criticism in detail, had it touched the main question, as is only fair, would have exposed, it may be my error, or it may be my reviewer's measure of insight into this species of research. It was, moreover, not a badly conceived plan, in order at once to take from readers (who are accustomed to form their conceptions of books from newspaper reports) the desire to read the book itself, to pour out in one breath a number of passages in succession, torn from their connexion, and their grounds of proof and explanations, and which must necessarily sound senseless, especially considering how antipathetic they are to all school-metaphysics; to exhaust the reader's patience ad nauseam, and then, after having made me acquainted with the sensible proposition that persistent illusion is truth, to conclude with the crude paternal moralisation: to what end, then, the quarrel with accepted language, to what end, and whence, the idealistic distinction? A judgment which seeks all that is characteristic of my book, first supposed to be metaphysically heterodox, in a mere innovation of the nomenclature, proves clearly that my would-be judge has understood nothing of the subject, and in addition, has not understood himself.⁴⁷

Beyond this, I find nothing else remarkable in the review of my book. The reviewer criticizes here and there, making sweeping criticisms. This is a prudent approach, since it reveals neither knowledge nor ignorance. A single thorough, detailed criticism would have been fair, had it addressed the main question. It might have exposed my error, or it might have exposed how much insight my reviewer has into this kind of inquiry. The reviewer also had a fairly clever plan to discourage readers from reading the book itself. Such readers are accustomed to forming their impressions of books from newspaper reports. The reviewer poured out, in one breath, a series of passages torn from their context, proofs, and explanations. These passages must sound senseless, especially since they are so opposed to all school metaphysics. Having exhausted the reader's patience to the point of nausea, the reviewer then acquainted me with the sensible proposition that persistent illusion is truth. The review concluded with a crude, paternal lecture: why quarrel with accepted language, then? Why make the idealistic distinction, and where does it come from? This judgment treats everything distinctive about my book as a mere change in terminology. Yet the reviewer had first supposed those distinctive features to be metaphysically unorthodox. This clearly proves that my would-be judge has understood nothing of the subject and, moreover, has not understood himself.⁴⁷

My reviewer speaks like a man who is conscious of important and superior insight which he keeps hidden; for I am aware of nothing recent with respect to metaphysics that could justify his tone. But he should not withhold his discoveries from the world, for there are doubtless many who, like myself, have not been able to find in all the fine things that have for long past been written in this department, anything that has advanced the science by so much as a fingerbreadth; we find indeed the giving a new point to definitions, the supplying of lame proofs with new crutches, the adding to the crazy-quilt of metaphysics fresh patches or changing its pattern; but all this is not what the world requires. The world is tired of metaphysical assertions; it wants the possibility of the science, the sources from which certainty therein can be derived, and certain criteria by which it may distinguish the dialectical illusion of pure reason from truth. To this the critic seems to possess a key, otherwise he would never have spoken out in such a high tone.

My reviewer speaks like someone who knows something important and profound but keeps it hidden. For I know of nothing recent in metaphysics that could justify his tone. But he should not withhold his discoveries from the world. No doubt many others, like me, have found nothing in all the fine writing on metaphysics that has advanced the science even a finger's breadth. We do find definitions given a new twist, weak proofs propped up with new crutches, and the patchwork of metaphysics given fresh patches or a new pattern. But none of this is what the world needs. The world is tired of metaphysical assertions. It wants to know whether metaphysics is possible as a science, where certainty in it can come from, and how to distinguish truth from the deceptive illusions of pure reason. The critic seems to have a key to these questions. Otherwise, he would never have spoken so loftily.

But I am inclined to suspect that no such requirement of the science has ever entered his thoughts, for in that case he would have directed his judgment to this point, and even a mistaken attempt in such an important matter, would have won his respect. If that be the case, we are once more good friends. He may penetrate as deeply as he likes into metaphysics, without any one hindering him; only as concerns that which lies outside metaphysics, its sources, which are to be found in reason, he cannot form a judgment. That my suspicion is not without foundation, is proved by the fact that he does not mention a word about the possibility of synthetic knowledge a priori, the special problem upon the solution of which the fate of metaphysics wholly rests, and upon which my Critique (as well as the present Prolegomena) entirely hinges. The Idealism he encountered, and which he hung upon, was only taken up in the doctrine as the sole means of solving the above problem (although it received its confirmation on other grounds), and hence he must have shown either that the above problem does not possess the importance I attribute to it (even in these Prolegomena), or that by my conception of appearances, it is either not solved at all, or can be better solved in another way; but I do not find a word of this in the criticism. The reviewer, then, understands nothing of my work, and possibly also nothing of the spirit and essential nature of metaphysics itself; and it is not, what I would rather assume, the hurry of a man incensed at the labor of plodding through so many obstacles, that threw an unfavorable shadow over the work lying before him, and made its fundamental features unrecognisable.

But I suspect that he has never even considered this requirement of the science. If he had, he would have directed his judgment toward it. Even a mistaken attempt to address such an important matter would have won his respect. If that is the case, we are good friends again. He may explore metaphysics as deeply as he likes, without anyone stopping him. But he cannot judge what lies outside metaphysics: its sources in reason. My suspicion is not without foundation. He says not a word about the possibility of synthetic knowledge a priori. This is the special problem on whose solution the fate of metaphysics wholly depends. My Critique, like the present Prolegomena, turns entirely on this problem. He encountered Idealism and seized on it. But Idealism was introduced into the doctrine only as the sole means of solving that problem, although it was confirmed on other grounds. He therefore had to show one of two things. Either the problem does not have the importance I give it, even in these Prolegomena. Or my conception of appearances either does not solve it at all or leaves it open to a better solution. But I find not a word about any of this in the review. The reviewer, then, understands nothing of my work. He may also understand nothing of the spirit and essential nature of metaphysics itself. I would rather assume another explanation. Perhaps he was in a hurry and angered by the labor of plodding through so many obstacles. Perhaps this cast an unfavorable shadow over the work before him, making its fundamental features unrecognizable. But that is not the case.

There is a good deal to be done before a learned journal, it matters not with what care its writers may be selected, can maintain its otherwise well-merited reputation, in the field of metaphysics as elsewhere. Other sciences and branches of knowledge have their standard. Mathematics has it, in itself; history and theology, in profane or sacred books; natural science and the art of medicine, in mathematics and experience; jurisprudence, in law books; and even matters of taste in the examples of the ancients. But for the judgment of the thing called metaphysics, the standard has yet to be found. I have made an attempt to determine it, as well as its use. What is to be done, then, until it be found, when works of this kind have to be judged of? If they are of a dogmatic character, one may do what one likes; no one will play the master over others here for long, before someone else appears to deal with him in the same manner. If, however, they are critical in their character, not indeed with reference to other works, but to reason itself, so that the standard of judgment cannot be assumed but has first of all to be sought for, then, though objection and blame may indeed be permitted, yet a certain degree of leniency is indispensable, since the need is common to us all, and the lack of the necessary insight makes the high-handed attitude of judge unwarranted.

A learned journal has much work to do before it can maintain its otherwise well-deserved reputation in metaphysics as elsewhere. This is true no matter how carefully its writers are chosen. Other sciences and branches of knowledge have standards. Mathematics has its standard within itself. History and theology have theirs in secular or sacred books. Natural science and medicine have theirs in mathematics and experience. Jurisprudence has its standard in law books, and even matters of taste have theirs in the examples of the ancients. But a standard for judging what is called metaphysics has yet to be found. I have tried to determine this standard and how to use it. What, then, should be done when such works must be judged before the standard is found? If they are dogmatic, one may do as one likes. No one will act as master over others here for long before someone else appears and treats him the same way. But some works are critical, not of other works, but of reason itself. In that case, the standard of judgment cannot be assumed and must first be sought. Objections and criticism may indeed be permitted, but some leniency is essential. We all share the need for a standard, and our lack of the necessary insight makes a high-handed attitude as judge unwarranted.

In order, however, to connect my defence with the interest of the philosophical commonwealth, I propose a test, which must be decisive as to the mode, whereby all metaphysical investigations may be directed to their common purpose. This is nothing more than what formerly mathematicians have done, in establishing the advantage of their methods by competition. I challenge my critic to demonstrate, as is only just, on a priori grounds, in his way, a single really metaphysical principle asserted by him. Being metaphysical it must be synthetic and cognised a priori from conceptions, but it may also be any one of the most indispensable principles, as for instance, the principle of the persistence of substance, or of the necessary determination of events in the world by their causes. If he cannot do this (silence however is confession), he must admit, that as metaphysics without apodeictic certainty of propositions of this kind is nothing at all, its possibility or impossibility must before all things be established in a critique of the pure reason. Thus he is bound either to confess that my principles in the Critique are correct, or he must prove their invalidity. But as I can already foresee, that, confidently as he has hitherto relied on the certainty of his principles, when it comes to a strict test he will not find a single one in the whole range of metaphysics he can bring forward, I will concede to him an advantageous condition, which can only be expected in such a competition, and will relieve him of the onus probandi by laying it on myself.

To connect my defense with the interests of the philosophical community, I propose a test. It must settle how all metaphysical investigations should be directed toward their common purpose. This is just what mathematicians once did when they tested the advantages of their methods against one another. I challenge my critic to prove, using his own method and a priori reasoning, a single genuinely metaphysical principle he asserts. This is only fair. Because the principle is metaphysical, it must be synthetic and knowable a priori from concepts. He may choose even one of the most indispensable principles. For example, he may choose the principle that substance persists, or that causes necessarily determine events in the world. If he cannot do this, he must admit that metaphysics is nothing without apodictic certainty about such propositions. He must also admit that a critique of pure reason must first establish whether metaphysics is possible or impossible. Silence, however, is an admission of failure. He must therefore either admit that my principles in the Critique are correct or prove them invalid. But I can already foresee that he will not find a single principle in all of metaphysics to put forward under strict examination. This is so despite his confidence in the certainty of his principles until now. I will therefore grant him an advantage that can only be expected in such a competition. I will relieve him of the burden of proof and take it upon myself.

He finds in these Prolegomena and in my Critique (chapter on the "Theses and Antitheses of the Four Antinomies") eight propositions, of which two and two contradict one another, but each of which necessarily belongs to metaphysics, by which it must either be accepted or rejected (although there is not one that has not in this time been held by some philosopher). Now he has the liberty of selecting any one of these eight propositions at his pleasure, and accepting it without any proof, of which I shall make him a present, but only one (for waste of time will be just as little serviceable to him as to me), and then of attacking my proof of the opposite proposition. If I can save this one, and at the same time show, that according to principles which every dogmatic metaphysics must necessarily recognise, the opposite of the proposition adopted by him can be just as clearly proved, it is thereby established that metaphysics has an hereditary failing, not to be explained, much less set aside, until we ascend to its birth-place, pure reason itself, and thus my Critique must either be accepted or a better one take its place; it must at least be studied, which is the only thing I now require. If, on the other hand, I cannot save my demonstration, then a synthetic proposition a priori from dogmatic principles is to be reckoned to the score of my opponent, then also I will deem my impeachment of ordinary metaphysics as unjust, and pledge myself to recognise his stricture on my Critique as justified (although this would not be the consequence by a long way). To this end it would be necessary, it seems to me, that he should step out of his incognito. Otherwise I do not see how it could be avoided, that instead of dealing with one, I should be honored by several problems coming from anonymous and unqualified opponents.

In these Prolegomena and in my Critique, he finds eight propositions in the chapter on the "Theses and Antitheses of the Four Antinomies." The propositions contradict one another in pairs. Each necessarily belongs to metaphysics, which must either accept or reject it. And every one of them has been held by some philosopher in our time. He is free to choose any one of these eight propositions and accept it without proof. I will grant him that much, but only for one proposition. Wasting time will be no more useful to him than to me. He may then attack my proof of the opposite proposition. Suppose I can defend my proof. Suppose I can also show that the opposite of his chosen proposition can be proved just as clearly. The proof must use principles that every dogmatic metaphysics must necessarily recognize. This would establish that metaphysics has an inherited defect. We cannot explain this defect, much less remove it, until we go back to its birthplace, pure reason itself. My Critique must therefore either be accepted or replaced by a better one. At the very least, it must be studied, which is all I ask for now. If, on the other hand, I cannot defend my demonstration, my opponent can claim a synthetic proposition a priori derived from dogmatic principles. I will then also consider my charge against ordinary metaphysics unjust. And I pledge to recognize his criticism of my Critique as justified, although that would be far from following as a consequence. For this purpose, it seems to me, he would need to reveal his identity. Otherwise, I do not see how I could avoid having to deal with several problems from anonymous and unqualified opponents, rather than one.

PROPOSALS AS TO AN INVESTIGATION OF THE CRITIQUE UPON WHICH A JUDGMENT MAY FOLLOW.

PROPOSALS FOR EXAMINING THE CRITIQUE SO THAT A JUDGMENT MAY FOLLOW.

I feel obliged to the honored public even for the silence with which it for a long time favored my Critique, for this proves at least a postponement of judgment, and some supposition that in a work, leaving all beaten tracks and striking out on a new path, in which one cannot at once perhaps so easily find one's way, something may perchance lie, from which an important but at present dead branch of human knowledge may derive new life and productiveness. Hence may have originated a solicitude for the as yet tender shoot, lest it be destroyed by a hasty judgment. A test of a judgment, delayed for the above reasons, is now before my eye in the Gothaischen gelehrten Zeitung, the thoroughness of which every reader will himself perceive, from the clear and unperverted presentation of a fragment of one of the first principles of my work, without taking into consideration my own suspicious praise.

I am grateful to the respected public, even for its long silence about my Critique. At least this silence shows that people held back their judgment. It also suggests that some thought the work might contain something valuable. The work leaves all familiar paths and takes a new one, where readers may not find their way so easily at first. What it contains might give new life and productivity to an important but currently dead branch of human knowledge. This may have led people to protect the still tender shoot from destruction by a hasty judgment. I now have before me a review in the Gothaischen gelehrten Zeitung, which offers an example of judgment delayed for these reasons. Every reader can see how thorough the review is from its clear and accurate presentation of part of one of the first principles of my work. No one needs to rely on my own praise, which may be suspect.

And now I propose, since an extensive structure cannot be judged of as a whole from a hurried glance, to test it piece by piece from its foundations, so thereby the present Prolegomena may fitly be used as a general outline with which the work itself may occasionally be compared. This notion, if it were founded on nothing more than my conceit of importance, such as vanity commonly attributes to one's own productions, would be immodest and would deserve to be repudiated with disgust. But now, the interests of speculative philosophy have arrived at the point of total extinction, while human reason hangs upon them with inextinguishable affection, and only after having been ceaselessly deceived does it vainly attempt to change this into indifference.

A large structure cannot be judged as a whole from a quick glance. So I propose to examine it piece by piece, starting with its foundations. These Prolegomena can then serve as a general outline for occasional comparison with the work itself. This proposal would be immodest and deserve to be rejected with disgust if it rested only on my own opinion of its importance. Vanity often leads people to attach such importance to their own work. But interest in speculative philosophy has now nearly died out entirely. Human reason, however, remains devoted to it with an undying affection. Only after being deceived again and again does reason try in vain to turn that affection into indifference.

In our thinking age it is not to be supposed but that many deserving men would use any good opportunity of working for the common interest of the more and more enlightened reason, if there were only some hope of attaining the goal. Mathematics, natural science, laws, arts, even morality, etc., do not completely fill the soul; there is always a space left over, reserved for pure and speculative reason, the vacuity of which prompts us to seek in vagaries, buffooneries, and myticism for what seems to be employment and entertainment, but what actually is mere pastime; in order to deaden the troublesome voice of reason, which in accordance with its nature requires something that can satisfy it, and not merely subserve other ends or the interests of our inclinations. A consideration, therefore, which is concerned only with reason as it exists for it itself, has as I may reasonably suppose a great fascination for every one who has attempted thus to extend his conceptions, and I may even say a greater than any other theoretical branch of knowledge, for which he would not willingly exchange it, because here all other cognitions, and even purposes, must meet and unite themselves in a whole.

In our age of thought, many worthy people would surely welcome a chance to work for the common interest of reason as it becomes more enlightened, if only there were some hope of reaching that goal. Mathematics, natural science, law, the arts, and even morality do not completely occupy the mind. There is always room left for pure and speculative reason. This empty space prompts us to seek apparent activity and entertainment in whims, foolishness, and mysticism. But these are really just ways of passing the time. We turn to them to silence the troublesome voice of reason. By its nature, reason demands something that can satisfy it, not merely serve other purposes or the interests of our desires. An inquiry concerned only with reason as it exists for itself is therefore, I may reasonably suppose, deeply fascinating to anyone who has tried to broaden their understanding in this way. I may even say that it fascinates them more than any other branch of theoretical knowledge. They would not willingly exchange it for any other, because all other knowledge, and even our purposes, must meet and unite in a whole here.

I offer, therefore, these Prolegomena as a sketch and text-book for this investigation, and not the work itself. Although I am even now perfectly satisfied with the latter as far as contents, order, and mode of presentation, and the care that I have expended in weighing and testing every sentence before writing it down, are concerned (for it has taken me years to satisfy myself fully, not only as regards the whole, but in some cases even as to the sources of one particular proposition); yet I am not quite satisfied with my exposition in some sections of the doctrine of elements, as for instance in the deduction of the conceptions of the Understanding, or in that on the paralogisms of pure reason, because a certain diffuseness takes away from their clearness, and in place of them, what is here said in the Prolegomena respecting these sections, may be made the basis of the test.

I offer these Prolegomena, then, as an outline and textbook for this investigation, not as the work itself. Even now, I am completely satisfied with the work’s content, order, and presentation. I am also satisfied with the care I took to weigh and test every sentence before writing it down. It took me years to satisfy myself fully, not only about the work as a whole, but sometimes even about the sources of a single proposition. Yet I am not entirely satisfied with my explanation in some sections of the doctrine of elements. These include the deduction of the concepts of the Understanding and the section on the paralogisms of pure reason. Some wordiness makes these sections less clear. What I say about them here in the Prolegomena may instead serve as the basis for testing them.

It is the boast of the Germans that where steady and continuous industry are requisite, they can carry things farther than other nations. If this opinion be well founded, an opportunity, a business, presents itself, the successful issue of which we can scarcely doubt, and in which all thinking men can equally take part, though they have hitherto been unsuccessful in accomplishing it and in thus confirming the above good opinion. But this is chiefly because the science in question is of so peculiar a kind, that it can be at once brought to completion and to that enduring state that it will never be able to be brought in the least degree farther or increased by later discoveries, or even changed (leaving here out of account adornment by greater clearness in some places, or additional uses), and this is an advantage no other science has or can have, because there is none so fully isolated and independent of others, and which is concerned with the faculty of cognition pure and simple. And the present moment seems, moreover, not to be unfavorable to my expectation, for just now, in Germany, no one seems to know wherewith to occupy himself, apart from the so-called useful sciences, so as to pursue not mere play, but a business possessing an enduring purpose.

Germans boast that, where steady and continuous effort is required, they can accomplish more than other nations. If this opinion is well founded, an opportunity now presents itself. We can hardly doubt its successful outcome, and all thinking people can take part in it equally. Yet they have so far failed to complete the task and thus confirm this favorable opinion of themselves. But the opportunity is promising chiefly because the science in question is so unusual. It can be brought to completion once and for all. Later discoveries will never be able to advance or expand it in the slightest, or even change it. This leaves aside improvements in clarity in some places or additional uses. No other science has or can have this advantage. For no other science is so completely separate from and independent of other sciences, or concerned with the faculty of knowledge alone. The present moment also seems favorable to my expectations. For in Germany today, apart from the so-called useful sciences, no one seems to know how to occupy themselves with something that has a lasting purpose rather than being mere play.

To discover the means how the endeavors of the learned may be united in such a purpose, I must leave to others. In the meantime, it is my intention to persuade any one merely to follow my propositions, or even to flatter me with the hope that he will do so; but attacks, repetitions, limitations, or confirmation, completion, and extension, as the case may be, should be appended. If the matter be but investigated from its foundation, it cannot fail that a system, albeit not my own, shall be erected, that shall be a possession for future generations for which they may have reason to be grateful.

I must leave it to others to find a way to unite scholars in this purpose. Meanwhile, I intend to persuade someone merely to follow my propositions, or even to flatter me with the hope that he will do so. But attacks, repetitions, limitations, or confirmation, completion, and extension should be added, as appropriate. If the matter is investigated from its foundations, a system will surely be built, even if it is not my own. It will be a possession for future generations, one they may have reason to be grateful for.

It would lead us too far here to show what kind of metaphysics may be expected, when only the principles of criticism have been perfected, and how, because the old false feathers have been pulled out, she need by no means appear poor and reduced to an insignificant figure, but may be in other respects richly and respectably adorned. But other and great uses which would result from such a reform, strike one immediately. The ordinary metaphysics had its uses, in that it sought out the elementary conceptions of the pure understanding in order to make them clear through analysis, and definite by explanation. In this way it was a training for reason, in whatever direction it might be turned; but this was all the good it did; service was subsequently effaced when it favored conceit by venturesome assertions, sophistry by subtle distinctions and adornment, and shallowness by the ease with which it decided the most difficult problems by means of a little school-wisdom, which is only the more seductive the more it has the choice, on the one hand, of taking something from the language of science, and on the other from that of popular discourse, thus being everything to everybody, but in reality nothing at all. By criticism, however, a standard is given to our judgment, whereby knowledge may be with certainty distinguished from pseudo-science, and firmly founded, being brought into full operation in metaphysics; a mode of thought extending by degrees its beneficial influence over every other use of reason, at once infusing into it the true philosophical spirit. But the service also that metaphysics performs for theology, by making it independent of the judgment of dogmatic speculation, thereby assuring it completely against the attacks of all such opponents, is certainly not to be valued lightly. For ordinary metaphysics, although it promised the latter much advantage, could not keep this promise, and moreover, by summoning speculative dogmatics to its assistance, did nothing but arm enemies against itself. Mysticism, which can prosper in a rationalistic age only when it hides itself behind a system of school-metaphysics, under the protection of which it may venture to rave with a semblance of rationality, is driven from this, its last hiding-place, by critical philosophy. Last, but not least, it cannot be otherwise than important to a teacher of metaphysics, to be able to say with universal assent, that what he expounds is Science, and that thereby genuine services will be rendered to the commonweal.

It would take us too far afield to show what kind of metaphysics we may expect once the principles of critique are perfected. Nor can we show here how metaphysics may still be richly and respectably adorned in other ways. Having had its old false feathers plucked out, it need not look poor or cut an insignificant figure. But other great benefits of such a reform are immediately apparent. Traditional metaphysics had its uses. It sought out the basic concepts of the pure understanding, making them clear through analysis and precise through explanation. In this way, it trained reason for whatever direction reason might take. But that was all the good it did. Its benefits were later wiped out when it encouraged conceit through bold assertions, and sophistry through subtle distinctions and embellishments. It also encouraged shallowness by making the most difficult problems seem easy to settle with a little academic learning. This learning was all the more seductive because it could borrow both from scientific language and from ordinary speech. It could thus be everything to everybody, but in reality nothing at all. Critique, however, gives our judgment a standard for distinguishing knowledge from pseudo-science with certainty. When fully applied in metaphysics, it can establish knowledge on a firm foundation. This way of thinking gradually extends its beneficial influence to every other use of reason, bringing the true philosophical spirit to each. The service metaphysics performs for theology is also certainly not to be valued lightly. It makes theology independent of the judgments of dogmatic speculation, thereby securing it completely against attacks from all such opponents. Traditional metaphysics promised theology great benefits, but could not keep that promise. Moreover, by calling on speculative dogmatism for help, it only armed enemies against itself. Mysticism can flourish in a rationalistic age only by hiding behind a system of academic metaphysics. Under that protection, it can venture to indulge in fantasies that have the appearance of rationality. Critical philosophy drives mysticism from this, its last hiding place. Last, but not least, a teacher of metaphysics must surely find it important to be able to say, with universal agreement, that what he teaches is science. He can also say that it will thereby provide genuine benefits to the common good.