PREFACE TO FIRST EDITION

human reason has this peculiar fate that in one species of its knowledge it is burdened by questions which, as pre­scribed by the very nature of reason itself, it is not able to ignore, but which, as transcending all its powers, it is also not able to answer.

The perplexity into which it thus falls is not due to any fault of its own. It begins with principles which it has no option save to employ in the course of experience, and which this experience at the same time abundantly justifies it in using. Rising with their aid (since it is determined to this also by its own nature) to ever higher, ever more remote, conditions, it soon becomes aware that in this way—the questions never ceasing —its work must always remain incomplete; and it therefore finds itself compelled to resort to principles which overstep all possible empirical employ­ment, and which yet seem so unobjectionable that even ordinary consciousness readily accepts them. But by this procedure human reason precipitates itself into darkness and contradictions; and while it may indeed conjecture that these must be in some way due to concealed errors, it is not in a position to be able to detect them. For since the principles of which it is making use transcend the limits of experience, they are no longer subject to any empirical test. The battle-field of these endless controversies is called metaphysics.

Time was when metaphysics was entitled the Queen of all the sciences; and if the will be taken for the deed, the preeminent importance of her accepted tasks gives her every right to this title of honour. Now, however, the changed fashion of the time brings her only scorn; a matron outcast and forsaken, she mourns like Hecuba: Modo maxima rerum , tot generis natisque potens—nunc trahor exul , inops . ⁴

Her government, under the administration of the dogmatists , was at first despotic . But inasmuch as the legislation still bore traces of the ancient barbarism, her empire gradu­ally through intestine wars gave way to complete anarchy; and the sceptics , a species of nomads, despising all settled modes of life, broke up from time to time all civil society. Happily they were few in number, and were unable to prevent its being established ever anew, although on no uniform and self-consistent plan. In more recent times, it has seemed as if an end might be put to all these controversies and the claims of metaphysics receive final judgment, through a certain physiology of the human understanding—that of the celebrated Locke. But it has turned out quite otherwise. For however the attempt be made to cast doubt upon the pre­tensions of the supposed Queen by tracing her lineage to vulgar origins in common experience, this genealogy has, as a matter of fact, been fictitiously invented, and she has still continued to uphold her claims. Metaphysics has accord­ingly lapsed back into the ancient time-worn dogmatism, and so again suffers that depreciation from which it was to have been rescued. And now, after all methods, so it is believed, have been tried and found wanting, the prevailing mood is that of weariness and complete indifferentism —the mother, in all sciences, of chaos and night, but happily in this case the source, or at least the prelude, of their approaching reform and restoration. For it at least puts an end to that ill-applied industry which has rendered them thus dark, confused, and unserviceable.

But it is idle to feign indifference to such enquiries, the object of which can never be indifferent to our human nature. Indeed these pretended indifferentists , however they may try to disguise themselves by substituting a popular tone for the language of the Schools, inevitably fall back, in so far as they think at all, into those very metaphysical assertions which they profess so greatly to despise. None the less this indifference, showing itself in the midst of flourishing sciences, and affecting precisely those sciences, the knowledge of which, if attainable, we should least of all care to dispense with, is a phenomenon that calls for attention and reflection. It is obviously the effect not of levity but of the matured judgment ⁵ of the age, which refuses to be any longer put off with illusory knowledge. It is a call to reason to undertake anew the most difficult of all its tasks, namely, that of self-knowledge, and to institute a tribunal which will assure to reason its lawful claims, and dismiss all groundless pretensions, not by despotic decrees, but in accordance with its own eternal and unalterable laws. This tribunal is no other than the critique of pure reason .

I do not mean by this a critique of books and systems, but of the faculty of reason in general, in respect of all know­ledge after which it ⁶ may strive independently of all experience . It will therefore decide as to the possibility or impossi­bility of metaphysics in general, and determine its sources, its extent, and its limits—all in accordance with principles.

I have entered upon this path—the only one that has re­mained unexplored—and flatter myself that in following it I have found a way of guarding against all those errors which have hitherto set reason, in its non-empirical employment, at variance with itself. I have not evaded its questions by plead­ing the insufficiency of human reason. On the contrary, I have specified these questions exhaustively, accordihg to prin­ciples; and after locating the point at which, through mis­understanding, reason comes into conflict with itself, I have solved them to its complete satisfaction. The answer to these questions has not, indeed, been such as a dogmatic and vision­ary insistence upon knowledge might lead us to expect—that can be catered for only through magical devices, in which I am no adept. Such ways of answering them are, indeed, not within the intention of the natural constitution of our reason; and inasmuch as they have their source in misunderstanding, it is the duty of philosophy to counteract their deceptive in­fluence, no matter what prized and cherished dreams may have to be disowned. In this enquiry I have made completeness my chief aim, and I venture to assert that there is not a single metaphysical problem which has not been solved, or for the solution of which the key at least has not been supplied. Pure reason is, indeed, so perfect a unity that if its principle were insufficient for the solution of even a single one of all the questions to which it itself gives birth we should have no alternative but to reject the principle, since we should then no longer be able to place implicit reliance upon it in dealing with any one of the other questions.

While I am saying this I can fancy that I detect in the face of the reader an expression of indignation, mingled with con­tempt, at pretensions seemingly so arrogant and vain-glorious. Yet they are incomparably more moderate than the claims of all those writers who on the lines of the usual programme profess to prove the simple nature of the soul or the necessity of a first beginning of the world. For while such writers pledge themselves to extend human knowledge beyond all limits of possible experience, I humbly confess that this is entirely be­yond my power. I have to deal with nothing save reason itself and its pure thinking; and to obtain complete knowledge of these, there is no need to go far afield, since I come upon them in my own self. Common logic itself supplies an example, how all the simple acts of reason can be enumerated completely and systematically. The subject of the present enquiry is the [kindred] question, how much we can hope to achieve by reason, when all the material and assistance of experience are taken away.

So much as regards completeness in our determination of each question, and exhaustiveness in our determination of all the questions with which we have to deal. These questions are not arbitrarily selected; they are prescribed to us, by the very nature of knowledge itself, as being the subject-matter of our critical enquiry.

As regards the form of our enquiry, certainty and clearness are two essential requirements, rightly to be exacted from any­one who ventures upon so delicate an undertaking.

As to certainty , I have prescribed to myself the maxim, that in this kind of investigation it is in no wise permissible to hold opinions . Everything, therefore, which bears any manner of resemblance to an hypothesis is to be treated as contra­band; it is not to be put up for sale even at the lowest price, but forthwith confiscated, immediately upon detection. Any knowledge that professes to hold a priori lays claim to be regarded as absolutely necessary. This applies still more to any determination of all pure a priori knowledge, since such deterinmation has to serve as the measure, and therefore as the [supreme] example, of all apodeictic (philosophical) certainty. Whether I have succeeded in what I have undertaken must be left altogether to the reader’s judgment; the author’s task is solely to adduce grounds, not to speak as to the effect which they should have upon those who are sitting in judgment, But the author, in order that he may not himself, innocently, be the cause of any weakening of his arguments, may be permitted to draw attention to certain passages, which, although merely incidental, may yet occasion some mistrust. Such timely inter­vention may serve to counteract the influence which even quite undefined doubts as to these minor matters might otherwise exercise upon the reader’s attitude in regard to the main issue.

I know no enquiries which are more important for ex­ploring the faculty which we entitle understanding, and for determining the rules and limits of its employment, than those which I have instituted in the second chapter of the Trans­cendental Analytic under the title Deduction of the Pure Concepts of Understanding . They are also those which have cost me the greatest labour—labour, as I hope, not unre­warded. This enquiry, which is somewhat deeply grounded, has two sides. The one refers to the objects of pure under­standing, and is intended to expound and render intelligible the objective validity of its a priori concepts. It is therefore essential to my purposes. The other seeks to investigate the pure understanding itself, its possibility and the cognitive faculties upon which it rests; and so deals with it in its sub­jective aspect. Although this latter exposition is of great importance for my chief purpose, it does not form an essential part of it. For the chief question is always simply this:—what and how much can the understanding and reason know apart from all experience? not:—how is the faculty of thought itself possible? The latter is, as it were, the search for the cause of a given effect, and to that extent is somewhat hypothetical in character (though, as I shall show elsewhere, it is not really so); and I would appear to be taking the liberty simply of expressing an opinion , in which case the reader would be free to express a different opinion . For this reason I must forestall the reader’s criticism by pointing out that the objective de­duction with which I am here chiefly concerned retains its full force even if my subjective deduction should fail to produce that complete conviction for which I hope. On this matter, what has been said on pp. 92-93 ⁷ should in any case suffice by itself.

As regards clearness , the reader has a right to demand, in the first place, a discursive (logical) clearness, through concepts , and secondly, an intuitive (aesthetic) clearness, through intuitions , that is, through examples and other concrete illustrations. For the first I have sufficiently provided. That was essential to my purpose; but it has also been the incidental cause of my not being in a position to do justice to the second demand, which, if not so pressing, is yet still quite reasonable. I have been almost continuously at a loss, during the progress of my work, how I should proceed in this matter. Examples and illustrations seemed always to be necessary, and so took their place, as required, in my first draft. But I very soon became aware of the magnitude of my task and of the multi­plicity of matters with which I should have to deal; and as I perceived that even if treated in dry, purely scholastic fashion, the outcome would by itself be already quite suffi­ciently large in bulk, I found it inadvisable to enlarge it yet further through examples and illustrations. These are neces­sary only from a popular point of view; and this work can never be made suitable for popular consumption. Such assistance is not required by genuine students of the science, and, though always pleasing, might very well in this case have been self-defeating in its effects. Abbot Terrasson ⁸ has remarked that if the size of a volume be measured not by the number of its pages but by the time required for mastering it, it can be said of many a book, that it would be much shorter if it were not so short . On the other hand, if we have in view the comprehensibility of a whole of speculative knowledge, which, though wide-ranging, has the coherence that follows from unity of principle, we can say with equal justice that many a book would have been much clearer if it had not made such an effort to be clear. For the aids to clearness, though they may be of assistance ⁹ in regard to details, often interfere with our grasp of the whole. The reader is not allowed to arrive sufficiently quickly at a conspectus of the whole; the bright colouring of the illustrative material intervenes to cover over and conceal the articulation and organisation of the system, which, if we are to be able to judge of its unity and solidity, are what chiefly concern us.

The reader, I should judge, will feel it to be no small inducement to yield his willing co-operation, when the author is thus endeavouring, according to the plan here proposed, to carry through a large and important work in a complete and lasting manner. Metaphysics, on the view which we are adopting, is the only one of all the sciences which dare promise that through a small but concentrated effort it will attain, and this in a short time, such completion as will leave no task to our successors save that of adapting it in a didactic manner according to their own preferences, without their being able to add anything whatsoever to its content. For it is nothing but the inventory of all our possessions through pure reason, systematically arranged. In this field nothing can escape us. What reason produces entirely out of itself cannot be concealed, but is brought to light by reason itself immediately the common principle has been discovered. The complete unity of this kind of knowledge, and the fact that it is derived solely from pure concepts, entirely unin­fluenced by any experience or by special intuition, such as might lead to any determinate experience that would enlarge and increase it, make this unconditioned completeness not only practicable but also necessary. Tecum habita , et noris quam sit tibi carta supelle x ¹⁰ .

Such a system of pure (speculative) reason I hope myself to produce under the title Metaphysics of Nature . It will be not half as large, yet incomparably richer in content than this present Critique , which has as its first task to discover the sources and conditions of the possibility of such criticism, clearing, as it were, and levelling what has hitherto been waste-ground. In this present enterprise I look to my reader for the patience and impartiality of a judge ; whereas in the other. I shall look for the benevolent assistance of a fellow-worker . For however completely all the principles of the system are presented in this Critique , the completeness of the system itself likewise requires that none of the derivative concepts be lacking. These cannot be enumerated by any a priori com­putation, but must be discovered gradually. Whereas, there­fore, in this Critique the entire synthesis of the concepts has been exhausted, there will still remain the further work of making their analysis similarly complete, a task which is rather an amusement than a labour.

I have only a few remarks to add of a typographical character. As the beginning of the printing was delayed, I was not able to see more than about half of the proof-sheets, and I now find some misprints, which do not, however, affect the sense except on p. 738, line 4 from the bottom ¹¹ , where specific has to be read in place of sceptical. The antinomy of pure reason, from p. 832 to p. 904, ¹² has been so arranged, in tabular form, that all that belongs to the thesis stands on the left and what belongs to the antithesis on the right. This I have done in order that proposition and counter-proposition may be the more easily compared with one another. RneYd7pUZYJaD03QFKePIYGZKdKHMBGEJeGhYtLrTpOr/oXSku2eI8eX+0tG2fDn