Introduction

THESE Prolegomena are destined for the use, not of pupils, but of future teachers, and even the latter should not expect that they will be serviceable for the systematic exposition of a ready-made science, but merely for the discovery of the science itself.

These Prolegomena are intended not for students, but for future teachers. Even future teachers should not expect them to help present an established science systematically. Instead, the Prolegomena are meant only to help discover the science itself.

There are scholarly men, to whom the history of philosophy (both ancient and modern) is philosophy itself; for these the present Prolegomena are not written. They must wait till those who endeavor to draw from the fountain of reason itself have completed their work; it will then be the historian's turn to inform the world of what has been done. Unfortunately, nothing can be said, which in their opinion has not been said before, and truly the same prophecy applies to all future time; for since the human reason has for many centuries speculated upon innumerable objects in various ways, it is hardly to be expected that we should not be able to discover analogies for every new idea among the old sayings of past ages.

Some scholars consider the history of philosophy, both ancient and modern, to be philosophy itself. These Prolegomena are not written for them. They must wait until those who seek knowledge from the fountain of reason itself have completed their work. Then it will be the historian’s turn to tell the world what has been done. Unfortunately, in their opinion, nothing can be said that has not been said before. And the same prediction surely applies to all future time. For centuries, human reason has speculated in many ways about countless subjects. So we can hardly expect to find a new idea without some parallel among the old sayings of past ages.

My object is to persuade all those who think Metaphysics worth studying, that it is absolutely necessary to pause a moment, and, neglecting all that has been done, to propose first the preliminary question, ‘Whether such a thing as metaphysics be at all possible?’

My aim is to persuade all who think metaphysics is worth studying that they must first pause for a moment. They must set aside everything that has been done and ask the preliminary question: ‘Is metaphysics possible at all?’

If it be a science, how comes it that it cannot, like other sciences, obtain universal and permanent recognition? If not, how can it maintain its pretensions, and keep the human mind in suspense with hopes, never ceasing, yet never fulfilled? Whether then we demonstrate our knowledge or our ignorance in this field, we must come once for all to a definite conclusion respecting the nature of this so-called science, which cannot possibly remain on its present footing. It seems almost ridiculous, while every other science is continually advancing, that in this, which pretends to be Wisdom incarnate, for whose oracle every one inquires, we should constantly move round the same spot, without gaining a single step. And so its followers having melted away, we do not find men confident of their ability to shine in other sciences venturing their reputation here, where everybody, however ignorant in other matters, may deliver a final verdict, as in this domain there is as yet no standard weight and measure to distinguish sound knowledge from shallow talk.

If metaphysics is a science, why can it not gain universal and lasting recognition, like other sciences? If it is not a science, how can it maintain its claims? How can it keep the human mind waiting with hopes that never cease but are never fulfilled? Whether we show that we have knowledge or ignorance in this field, we must settle the question once and for all. We must reach a definite conclusion about the nature of this so-called science, which cannot possibly remain as it is. Every other science is continually advancing. Yet it seems almost ridiculous that we keep going in circles in metaphysics without gaining a single step. Metaphysics claims to be wisdom itself, and everyone seeks answers from it as if from an oracle. Its followers have therefore dwindled away. Those who are confident of their ability to excel in other sciences do not venture their reputations in metaphysics. Here, everyone may deliver a final verdict, however ignorant they may be in other matters. For metaphysics still has no standard by which to distinguish sound knowledge from shallow talk.

After all it is nothing extraordinary in the elaboration of a science, when men begin to wonder how far it has advanced, that the question should at last occur, whether and how such a science is possible? Human reason so delights in constructions, that it has several times built up a tower, and then razed it to examine the nature of the foundation. It is never too late to become wise; but if the change comes late, there is always more difficulty in starting a reform.

After all, as a science develops, people begin to wonder how far it has advanced. It is not unusual for them eventually to ask whether and how such a science is possible. Human reason delights so much in building that it has built a tower several times, only to tear it down and examine its foundation. It is never too late to become wise, but the later wisdom comes, the harder it is to begin reforming.

The question whether a science be possible, presupposes a doubt as to its actuality. But such a doubt offends the men whose whole possessions consist of this supposed jewel; hence he who raises the doubt must expect opposition from all sides. Some, in the proud consciousness of their possessions, which are ancient, and therefore considered legitimate, will take their metaphysical compendia in their hands, and look down on him with contempt; others, who never see anything except it be identical with what they have seen before, will not understand him, and everything will remain for a time, as if nothing had happened to excite the concern, or the hope, for an impending change.

To ask whether a science is possible assumes that there is some doubt about whether it actually exists. But such doubt offends those whose entire wealth consists of this supposed jewel. So anyone who raises the doubt must expect opposition from all sides. Some are proudly aware of their possessions, which are ancient and therefore considered legitimate. They will take up their summaries of metaphysics and look down on him with contempt. Others see nothing unless it is identical to what they have seen before, so they will not understand him. For a time, everything will remain as if nothing had happened to cause concern or hope for an impending change.

Nevertheless, I venture to predict that the independent reader of these Prolegomena will not only doubt his previous science, but ultimately be fully persuaded, that it cannot exist unless the demands here stated on which its possibility depends, be satisfied; and, as this has never been done, that there is, as yet, no such thing as Metaphysics. But as it can never cease to be in demand,⁵—since the interests of common sense are intimately interwoven with it, he must confess that a radical reform, or rather a new birth of the science after an original plan, are unavoidable, however men may struggle against it for a while.

Nevertheless, I venture to predict that an independent reader of these Prolegomena will doubt their previous understanding of metaphysics. Ultimately, the reader will be fully convinced that metaphysics cannot exist unless the requirements stated here are met. Since those requirements have never been met, there is as yet no such thing as metaphysics. But metaphysics can never cease to be in demand,⁵ because the interests of common sense are closely bound up with it. The reader must therefore admit that a radical reform is unavoidable. Rather, metaphysics must be born anew according to an original plan, however much people may resist it for a while.

Since the Essays of Locke and Leibnitz, or rather since the origin of metaphysics so far as we know its history, nothing has ever happened which was more decisive to its fate than the attack made upon it by David Hume. He threw no light on this species of knowledge, but he certainly struck a spark from which light might have been obtained, had it caught some inflammable substance and had its smouldering fire been carefully nursed and developed.

Since the Essays of Locke and Leibnitz, nothing has affected the fate of metaphysics more decisively than David Hume’s attack. In fact, nothing has been more decisive since metaphysics began, as far as we know its history. Hume shed no light on this kind of knowledge. But he certainly struck a spark that could have produced light, if it had caught some flammable material. The smoldering fire would also have needed careful tending and development.

Hume started from a single but important concept in Metaphysics, viz., that of Cause and Effect (including its derivatives force and action, etc.). He challenges reason, which pretends to have given birth to this idea from herself, to answer him by what right she thinks anything to be so constituted, that if that thing be posited, something else also must necessarily be posited; for this is the meaning of the concept of cause. He demonstrated irrefutably that it was perfectly impossible for reason to think a priori and by means of concepts a combination involving necessity. We cannot at all see why, in consequence of the existence of one thing, another must necessarily exist, or how the concept of such a combination can arise a priori. Hence he inferred, that reason was altogether deluded with reference to this concept, which she erroneously considered as one of her children, whereas in reality it was nothing but a bastard of imagination, impregnated by experience, which subsumed certain representations under the Law of Association, and mistook the subjective necessity of habit for an objective necessity arising from insight. Hence he inferred that reason had no power to think such combinations, even generally, because her concepts would then be purely fictitious, and all her pretended a priori cognitions nothing but common experiences marked with a false stamp. In plain language there is not, and cannot be, any such thing as metaphysics at all.⁶

Hume began with a single but important concept in metaphysics: cause and effect, including related concepts such as force and action. Reason claims to have produced this idea on its own. Hume challenges reason to explain its grounds for thinking that anything is constituted in such a way that, if it exists, something else must necessarily exist too. For that is what the concept of cause means. He proved beyond dispute that reason cannot possibly think of a necessary connection a priori, using concepts alone. We cannot see at all why one thing’s existence must necessarily lead to another’s. Nor can we see how the concept of such a connection can arise a priori. Hume therefore concluded that reason was completely mistaken about this concept. Reason wrongly regarded it as one of its own children. In reality, it was nothing but a bastard child of imagination, conceived through experience. Imagination had grouped certain representations under the Law of Association. It had mistaken the subjective necessity of habit for an objective necessity arising from insight. Hume therefore concluded that reason had no power to think of such connections, even in general. For its concepts would then be pure inventions, and all its supposed a priori knowledge would be nothing but ordinary experience falsely stamped as a priori. In plain language, there is not, and cannot be, any such thing as metaphysics at all.⁶

However hasty and mistaken Hume's conclusion may appear, it was at least founded upon investigation, and this investigation deserved the concentrated attention of the brighter spirits of his day as well as determined efforts on their part to discover, if possible, a happier solution of the problem in the sense proposed by him, all of which would have speedily resulted in a complete reform of the science.

However hasty and mistaken Hume's conclusion may seem, it was at least based on investigation. That investigation deserved the focused attention of the brightest minds of his day. They also should have made determined efforts to find, if possible, a better solution to the problem as Hume posed it. All of this would have quickly led to a complete reform of the science.

But Hume suffered the usual misfortune of metaphysicians, of not being understood. It is positively painful to see how utterly his opponents, Reid, Oswald, Beattie, and lastly Priestley, missed the point of the problem; for while they were ever taking for granted that which he doubted, and demonstrating with zeal and often with impudence that which he never thought of doubting, they so misconstrued his valuable suggestion that everything remained in its old condition, as if nothing had happened.

But Hume suffered the usual misfortune of metaphysicians: he was not understood. It is painful to see how completely his opponents, Reid, Oswald, Beattie, and finally Priestley, missed the point. They kept taking for granted the very thing Hume doubted. And they eagerly, and often brazenly, tried to prove what he had never thought to doubt. In doing so, they so misunderstood his valuable suggestion that everything remained as it was, as if nothing had happened.

The question was not whether the concept of cause was right, useful, and even indispensable for our knowledge of nature, for this Hume had never doubted; but whether that concept could be thought by reason a priori, and consequently whether it possessed an inner truth, independent of all experience, implying a wider application than merely to the objects of experience. This was Hume's problem. It was a question concerning the origin, not concerning the indispensable need of the concept. Were the former decided, the conditions of the use and the sphere of its valid application would have been determined as a matter of course.

The question was not whether the concept of cause was correct, useful, and even indispensable to our knowledge of nature. Hume had never doubted that. Rather, he asked whether reason could conceive of cause a priori. If so, the concept would have an inherent truth independent of all experience. This would mean that the concept applied more broadly than merely to objects of experience. This was Hume's problem. It concerned the origin of the concept, not whether the concept was indispensable. If the question of its origin were settled, the conditions for its use and its valid range of application would follow.

But to satisfy the conditions of the problem, the opponents of the great thinker should have penetrated very deeply into the nature of reason, so far as it is concerned with pure thinking,—a task which did not suit them. They found a more convenient method of being defiant without any insight, viz., the appeal to common sense. It is indeed a great gift of God, to possess right, or (as they now call it) plain common sense. But this common sense must be shown practically, by well-considered and reasonable thoughts and words, not by appealing to it as an oracle, when no rational justification can be advanced. To appeal to common sense, when insight and science fail, and no sooner—this is one of the subtile discoveries of modern times, by means of which the most superficial ranter can safely enter the lists with the most thorough thinker, and hold his own. But as long as a particle of insight remains, no one would think of having recourse to this subterfuge. For what is it but an appeal to the opinion of the multitude, of whose applause the philosopher is ashamed, while the popular charlatan glories and confides in it? I should think that Hume might fairly have laid as much claim to common sense as Beattie, and in addition to a critical reason (such as the latter did not possess), which keeps common sense in check and prevents it from speculating, or, if speculations are under discussion, restrains the desire to decide because it cannot satisfy itself concerning its own arguments. By this means alone can common sense remain sound. Chisels and hammers may suffice to work a piece of wood, but for steel-engraving we require an engraver's needle. Thus common sense and speculative understanding are each serviceable in their own way, the former in judgments which apply immediately to experience, the latter when we judge universally from mere concepts, as in metaphysics, where sound common sense, so called in spite of the inapplicability of the word, has no right to judge at all.

But to meet the demands of the problem, the opponents of the great thinker would have needed deep insight into how reason works in pure thought. That task did not suit them. They found an easier way to be defiant without understanding: they appealed to common sense. It is indeed a great gift from God to possess sound common sense, or plain common sense, as they now call it. But common sense must be demonstrated in practice, through well considered and reasonable thoughts and words. It should not be treated as an oracle when no rational justification can be offered. To appeal to common sense only when understanding and science fail is one of the subtle discoveries of modern times. It allows the most superficial ranter to take on the most thorough thinker and hold his own. But as long as someone has even a particle of understanding, he would not think of resorting to this trick. For what is it but an appeal to the opinion of the multitude? The philosopher is ashamed of the multitude's applause, while the popular charlatan takes pride in it and relies on it. I should think that Hume could fairly claim as much common sense as Beattie. Hume also had critical reason, which Beattie lacked. Critical reason keeps common sense in check and prevents it from speculating. Or, when speculations are under discussion, critical reason restrains the desire to reach a verdict because it cannot satisfy itself about its own arguments. Only in this way can common sense remain sound. Chisels and hammers may be enough to work a piece of wood, but engraving steel requires an engraver's needle. In the same way, common sense and speculative understanding are each useful in their own way. Common sense is useful for judgments that apply directly to experience. Speculative understanding is useful when we make universal judgments from concepts alone, as in metaphysics. There, what is called sound common sense, though the term does not apply, has no right to judge at all.

I openly confess, the suggestion of David Hume was the very thing, which many years ago first interrupted my dogmatic slumber, and gave my investigations in the field of speculative philosophy quite a new direction. I was far from following him in the conclusions at which he arrived by regarding, not the whole of his problem, but a part, which by itself can give us no information. If we start from a well-founded, but undeveloped, thought, which another has bequeathed to us, we may well hope by continued reflection to advance farther than the acute man, to whom we owe the first spark of light.

I openly admit that David Hume’s suggestion first interrupted my dogmatic slumber many years ago. It gave my investigations in speculative philosophy an entirely new direction. I was far from following Hume to his conclusions. He had considered only part of his problem, not the whole of it, and that part alone can tell us nothing. If we start with a sound but undeveloped thought left to us by someone else, we may hope to advance further through continued reflection. We may go further than the insightful person who gave us the first spark of light.

I therefore first tried whether Hume's objection could not be put into a general form, and soon found that the concept of the connexion of cause and effect was by no means the only idea by which the understanding thinks the connexion of things a priori, but rather that metaphysics consists altogether of such connexions. I sought to ascertain their number, and when I had satisfactorily succeeded in this by starting from a single principle, I proceeded to the deduction of these concepts, which I was now certain were not deduced from experience, as Hume had apprehended, but sprang from the pure understanding. This deduction (which seemed impossible to my acute predecessor, which had never even occurred to any one else, though no one had hesitated to use the concepts without investigating the basis of their objective validity) was the most difficult task ever undertaken in the service of metaphysics; and the worst was that metaphysics, such as it then existed, could not assist me in the least, because this deduction alone can render metaphysics possible. But as soon as I had succeeded in solving Hume's problem not merely in a particular case, but with respect to the whole faculty of pure reason, I could proceed safely, though slowly, to determine the whole sphere of pure reason completely and from general principles, in its circumference as well as in its contents. This was required for metaphysics in order to construct its system according to a reliable method.

I therefore first tried to put Hume's objection into a general form. I soon found that cause and effect were by no means the only connection the understanding thinks of a priori. Rather, metaphysics consists entirely of such connections. I sought to determine how many there were, starting from a single principle. Once I had done this satisfactorily, I turned to the deduction of these concepts. I was now certain that they came from the pure understanding, not from experience, as Hume had supposed. This deduction was the most difficult task ever undertaken in the service of metaphysics. It had seemed impossible to my perceptive predecessor and had never even occurred to anyone else. Yet no one had hesitated to use these concepts without examining the basis of their objective validity. Worse still, metaphysics as it then existed could not help me at all, because only this deduction can make metaphysics possible. But once I had solved Hume's problem for the whole faculty of pure reason, not merely for one particular case, I could proceed safely, though slowly. I could determine the whole sphere of pure reason completely, from general principles, including both its boundaries and its contents. This was necessary for metaphysics to construct its system according to a reliable method.

But I fear that the execution of Hume's problem in its widest extent (viz., my Critique of the Pure Reason) will fare as the problem itself fared, when first proposed. It will be misjudged because it is misunderstood, and misunderstood because men choose to skim through the book, and not to think through it—a disagreeable task, because the work is dry, obscure, opposed to all ordinary notions, and moreover long-winded. I confess, however, I did not expect to hear from philosophers complaints of want of popularity, entertainment, and facility, when the existence of a highly prized and indispensable cognition is at stake, which cannot be established otherwise than by the strictest rules of methodic precision. Popularity may follow, but is inadmissible at the beginning. Yet as regards a certain obscurity, arising partly from the diffuseness of the plan, owing to which the principal points of the investigation are easily lost sight of, the complaint is just, and I intend to remove it by the present Prolegomena.

But I fear that my treatment of Hume's problem in its widest scope, my Critique of Pure Reason, will meet the same fate as the problem itself when first proposed. The book will be misunderstood and therefore misjudged. It will be misunderstood because people choose to skim it rather than think it through. Thinking it through is unpleasant because the work is dry, obscure, at odds with all ordinary ideas, and long-winded. Still, I confess that I did not expect philosophers to complain that the work was inaccessible, unentertaining, and difficult. After all, what is at stake is the existence of a highly prized and indispensable kind of knowledge. Such knowledge can be established only by following the strictest rules of systematic precision. The work may become accessible to a wider audience afterward, but that cannot be the starting point. Yet one complaint about obscurity is justified. It arises partly from the sprawling plan of the work, which makes the main points of the inquiry easy to lose sight of. I intend to remedy this obscurity with the present Prolegomena.

The first-mentioned work, which discusses the pure faculty of reason in its whole compass and bounds, will remain the foundation, to which the Prolegomena, as a preliminary exercise, refer; for our critique must first be established as a complete and perfected science, before we can think of letting Metaphysics appear on the scene, or even have the most distant hope of attaining it.

The first-mentioned work examines the full scope and limits of pure reason. It will remain the foundation to which the Prolegomena refer as a preliminary exercise. For our critique must first be established as a complete and perfected science. Only then can we think of presenting Metaphysics, or even have the faintest hope of attaining it.

We have been long accustomed to seeing antiquated knowledge produced as new by taking it out of its former context, and reducing it to system in a new suit of any fancy pattern under new titles. Most readers will set out by expecting nothing else from the Critique; but these Prolegomena may persuade him that it is a perfectly new science, of which no one has ever even thought, the very idea of which was unknown, and for which nothing hitherto accomplished can be of the smallest use, except it be the suggestion of Hume's doubts. Yet ever, he did not suspect such a formal science, but ran his ship ashore, for safety's sake, landing on scepticism, there to let it lie and rot; whereas my object is rather to give it a pilot, who, by means of safe astronomical principles drawn from a knowledge of the globe, and provided with a complete chart and compass, may steer the ship safely, whither he listeth.

We have long been used to seeing old knowledge presented as new. It is taken out of its original context and arranged into a system, dressed up in whatever new style someone fancies, and given new titles. Most readers will expect nothing else from the Critique. But these Prolegomena may persuade them that it presents an entirely new science. No one has ever even thought of this science, and its very idea was unknown. Nothing accomplished so far can be of the slightest use to it, except perhaps the suggestion provided by Hume's doubts. Yet even Hume did not suspect that such a formal science existed. Instead, he ran his ship ashore for safety, landing on skepticism and leaving the ship there to rot. My aim, by contrast, is to give the ship a pilot. Using reliable astronomical principles drawn from knowledge of the globe, and equipped with a complete chart and compass, the pilot can steer the ship safely wherever he chooses.

If in a new science, which is wholly isolated and unique in its kind, we started with the prejudice that we can judge of things by means of our previously acquired knowledge, which is precisely what has first to be called in question, we should only fancy we saw everywhere what we had already known, the expressions, having a similar sound, only that all would appear utterly metamorphosed, senseless and unintelligible, because we should have as a foundation our own notions, made by long habit a second nature, instead of the author's. But the longwindedness of the work, so far as it depends on the subject, and not the exposition, its consequent unavoidable dryness and its scholastic precision are qualities which can only benefit the science, though they may discredit the book.

Suppose we begin studying a new science that is entirely separate from other sciences and unique in its kind. If we assume that we can judge its claims by what we already know, we start with a prejudice. For our previous knowledge is precisely what must first be questioned. We would only imagine that we saw familiar ideas everywhere, because the expressions sounded similar. Yet everything would seem utterly transformed, senseless, and unintelligible. This would be because we had taken our own ideas as our foundation instead of the author's. Long habit has made our ideas second nature to us. But the work's length can only benefit the science, insofar as it results from the subject rather than the presentation. The same is true of its resulting and unavoidable dryness and its academic precision. Yet these qualities may bring the book into disrepute.

Few writers are gifted with the subtilty, and at the same time with the grace, of David Hume, or with the depth, as well as the elegance, of Moses Mendelssohn. Yet I flatter myself I might have made my own exposition popular, had my object been merely to sketch out a plan and leave its completion to others, instead of having my heart in the welfare of the science, to which I had devoted myself so long; in truth, it required no little constancy, and even self-denial, to postpone the sweets of an immediate success to the prospect of a slower, but more lasting, reputation.

Few writers have both the subtlety and grace of David Hume, or the depth and elegance of Moses Mendelssohn. Still, I believe I could have made my own account appealing to a wide audience. I could have done so if my aim had merely been to outline a plan and leave others to complete it. But I cared deeply about the welfare of the science to which I had devoted myself for so long. Indeed, it took considerable persistence and even self-denial to forgo the pleasures of immediate success for the prospect of a slower but more lasting reputation.

Making plans is often the occupation of an opulent and boastful mind, which thus obtains the reputation of a creative genius, by demanding what it cannot itself supply; by censuring, what it cannot improve; and by proposing, what it knows not where to find. And yet something more should belong to a sound plan of a general critique of pure reason than mere conjectures, if this plan is to be other than the usual declamations of pious aspirations. But pure reason is a sphere so separate and self-contained, that we cannot touch a part without affecting all the rest. We can therefore do nothing without first determining the position of each part, and its relation to the rest; for, as our judgment cannot be corrected by anything without, the validity and use of every part depends upon the relation in which it stands to all the rest within the domain of reason.

Making plans is often the pastime of a grand and boastful mind. Such a person gains a reputation for creative genius by demanding what they cannot provide, criticizing what they cannot improve, and proposing what they do not know where to find. Yet a sound plan for a general critique of pure reason must contain more than mere guesses. Otherwise, it is no different from the usual speeches expressing pious hopes. But pure reason is a realm so separate and self-contained that we cannot touch one part without affecting all the others. We can therefore do nothing without first determining the position of each part and its relation to the rest. Our judgment cannot be corrected by anything outside this realm. So the validity and use of every part depend on its relation to all the other parts within the realm of reason.

So in the structure of an organized body, the end of each member can only be deduced from the full conception of the whole. It may, then, be said of such a critique that it is never trustworthy except it be perfectly complete, down to the smallest elements of pure reason. In the sphere of this faculty you can determine either everything or nothing.

In the structure of an organized body, the purpose of each part can only be understood from a complete conception of the whole. Similarly, such a critique can be said to be trustworthy only if it is perfectly complete, down to the smallest elements of pure reason. In this faculty, you can determine either everything or nothing.

But although a mere sketch, preceding the Critique of Pure Reason, would be unintelligible, unreliable, and useless, it is all the more useful as a sequel. For so we are able to grasp the whole, to examine in detail the chief points of importance in the science, and to improve in many respects our exposition, as compared with the first execution of the work.

But a mere outline presented before the Critique of Pure Reason would be unintelligible, unreliable, and useless. As a follow-up, however, it is all the more useful. It allows us to grasp the whole and examine the main points of the science in detail. It also allows us to improve our presentation in many respects, compared with the first version of the work.

After the completion of the work I offer here such a plan which is sketched out after an analytical method, while the work itself had to be executed in the synthetical style, in order that the science may present all its articulations, as the structure of a peculiar cognitive faculty, in their natural combination. But should any reader find this plan, which I publish as the Prolegomena to any future Metaphysics, still obscure, let him consider that not every one is bound to study Metaphysics, that many minds will succeed very well, in the exact and even in deep sciences, more closely allied to practical experience,⁷ while they cannot succeed in investigations dealing exclusively with abstract concepts. In such cases men should apply their talents to other subjects. But he who undertakes to judge, or still more, to construct, a system of Metaphysics, must satisfy the demands here made, either by adopting my solution, or by thoroughly refuting it, and substituting another. To evade it is impossible.

Now that the work is complete, I offer this plan, outlined according to an analytical method. The work itself had to be written in the synthetic style. This was necessary so that the science could present all its parts in their natural connection, as the structure of a distinct cognitive faculty. But suppose a reader still finds this plan obscure. I publish it as the Prolegomena to any future Metaphysics. Let the reader consider that not everyone is obliged to study Metaphysics. Many minds will succeed very well in exact and even deep sciences that are more closely connected to practical experience,⁷ while they cannot succeed in inquiries dealing exclusively with abstract concepts. In such cases, people should apply their talents to other subjects. But anyone who undertakes to judge a system of Metaphysics, or still more to construct one, must meet the demands made here. They must either adopt my solution or thoroughly refute it and offer another. Evading these demands is impossible.

In conclusion, let it be remembered that this much-abused obscurity (frequently serving as a mere pretext under which people hide their own indolence or dullness) has its uses, since all who in other sciences observe a judicious silence, speak authoritatively in metaphysics and make bold decisions, because their ignorance is not here contrasted with the knowledge of others. Yet it does contrast with sound critical principles, which we may therefore commend in the words of Virgil:

In conclusion, remember that obscurity, much criticized as it is, has its uses. (People often use obscurity as a mere excuse to hide their own laziness or dullness.) All those who wisely remain silent in other sciences speak with authority and make bold judgments in metaphysics. They do so because, in metaphysics, their ignorance is not exposed by comparison with the knowledge of others. Yet their ignorance does stand in contrast to sound critical principles. We may therefore praise those principles in the words of Virgil:

"Ignavum, fucos, pecus a praesepibus arcent."

"They drive the drones, a lazy herd, from the hives."

"Bees are defending their hives against drones, those indolent creatures."

"Bees are defending their hives against drones, those lazy creatures."