and limitation of the faculties of the mind; I have, on the contrary, examined them completely in the light of principles, and, after having discovered the cause of the doubts and contradictions into which reason fell, have solved them to its perfect satisfaction. It is true, these questions have not been solved as dogmatism, in its vain fancies and desires, had expected; for it can only be satisfied by the exercise of magical arts, and of these I have no knowledge. But neither do these come within the compass of our mental powers; and it was the duty of philosophy to destroy the illusions which had their origin in misconceptions, whatever darling hopes and valued expectations may be ruined by its explanations. My chief aim in this work has been thoroughness; and I make bold to say that there is not a single metaphysical problem that does not find its solution, or at least the key to its solution, here. Pure reason is a perfect unity; and therefore, if the principle presented by it prove to be insufficient for the solution of even a single one of those questions to which the very nature of reason gives birth, we must reject it, as we could not be perfectly certain of its sufficiency in the case of the others.
While I say this, I think I see upon the countenance of the reader signs of dissatisfaction mingled with contempt, when he hears declarations which sound so boastful and extravagant; and yet they are beyond comparison more moderate than those advanced by the commonest author of the commonest philosophical programme, in which the dogmatist professes to demonstrate the simple nature of the soul, or the necessity of a primal being. Such a dogmatist promises to extend human knowledge beyond the limits of possible experience; while I humbly confess that this is completely beyond my power. Instead of any such attempt, I confine myself to the examination of reason alone and its pure thought; and I do not need to seek far for the sum-total of its cognition, because it has its seat in my own mind. Besides, common logic presents me with a complete and systematic catalogue of all the simple operations of reason; and it is my task to answer the question how far reason can go, without the material presented and the aid furnished by experience.
So much for the completeness and thoroughness necessary in the execution of the present task. The aims set before us are not arbitrarily proposed, but are imposed upon us by the nature of cognition itself.
The above remarks relate to the matter of our critical inquiry. As regards the form, there are two indispensable conditions, which any one who undertakes so difficult a task as that of a critique of pure reason, is bound to fulfil. These conditions are certitude and clearness.
As regards certitude, I have fully convinced myself that, in this sphere of thought, opinion is perfectly inadmissible, and that everything which bears the least semblance of an hypothesis must be excluded, as of no value in such discussions. For it is a necessary condition of every cognition that is to be established upon a priori grounds that it shall be held to be absolutely necessary; much more is this the case with an attempt to determine all pure a priori cognition, and to furnish the standard — and consequently an example — of all apodeictic (philosophical) certitude. Whether I have succeeded in what I professed to do, it is for the reader to determine; it is the author’s business merely to adduce grounds and reasons, without determining what influence these ought to have on the mind of his judges. But, lest anything he may have said may become the innocent cause of doubt in their minds, or tend to weaken the effect which his arguments might otherwise produce — he may be allowed to point out those passages which may occasion mistrust or difficulty, although these do not concern the main purpose of the present work. He does this solely with the view of removing from the mind of the reader any doubts which might affect his judgement of the work as a whole, and in regard to its ultimate aim.
I know no investigations more necessary for a full insight into the nature of the faculty which we call understanding, and at the same time for the determination of the rules and limits of its use, than those undertaken in the second chapter of the “Transcendental Analytic,” under the title of “Deduction of the Pure Conceptions of the Understanding”; and they have also cost me by far the greatest labour — labour which, I hope, will not remain uncompensated. The view there taken, which goes somewhat deeply into the subject, has two sides, The one relates to the objects of the pure understanding, and is intended to demonstrate and to render comprehensible the objective validity of its a priori conceptions; and it forms for this reason an essential part of the Critique. The other considers the pure understanding itself, its possibility and its powers of cognition — that is, from a subjective point of view; and, although this exposition is of great importance, it does not belong essentially to the main purpose of the work, because the grand question is what and how much can reason and understanding, apart from experience, cognize, and not, how is the faculty of thought itself possible? As the latter is an inquiry into the cause of a given effect, and has thus in it some semblance of an hypothesis (although, as I shall show on another occasion, this is really not the fact), it would seem that, in the present instance, I had allowed myself to enounce a mere opinion, and that the reader must therefore be at liberty to hold a different opinion. But I beg to remind him that, if my subjective deduction does not produce in his mind the conviction of its certitude at which I aimed, the objective deduction, with which alone the present work is properly concerned, is in every respect satisfactory.
As regards clearness, the reader has a right to demand, in the first place, discursive or logical clearness, that is, on the basis of conceptions, and, secondly, intuitive or aesthetic clearness, by means of intuitions, that is, by examples or other modes of illustration in concreto. I have done what I could for the first kind of intelligibility. This was essential to my purpose; and it thus became the accidental cause of my inability to do complete justice to the second requirement. I have been almost always at a loss, during the progress of this work, how to settle this question. Examples and illustrations always appeared to me necessary, and, in the first sketch of the Critique, naturally fell into their proper places. But I very soon became aware of the magnitude of my task, and the numerous problems with which I should be engaged; and, as I perceived that this critical investigation would, even if delivered in the driest scholastic manner, be far from being brief, I found it unadvisable to enlarge it still more with examples and explanations, which are necessary only from a popular point of view. I was induced to take this course from the consideration also that the present work is not intended for popular use, that those devoted to science do not require such helps, although they are always acceptable, and that they would have materially interfered with my present purpose. Abbe Terrasson remarks with great justice that, if we estimate the size of a work, not from the number of its pages, but from the time which we require to make ourselves master of it, it may be said of many a book that it would be much shorter, if it were not so short. On the other hand, as regards the comprehensibility of a system of speculative cognition, connected under a single principle, we may say with equal justice: many a book would have been much clearer, if it had not been intended to be so very clear. For explanations and examples, and other helps to intelligibility, aid us in the comprehension of parts, but they distract the attention, dissipate the mental power of the reader, and stand in the way of his forming a clear conception of the whole; as he cannot attain soon enough to a survey of the system, and the colouring and embellishments bestowed upon it prevent his observing its articulation or organization — which is the most important consideration with him, when he comes to judge of its unity and stability.
The reader must naturally have a strong inducement to co-operate with the present author, if he has formed the intention of erecting a complete and solid edifice of metaphysical science, according to the plan now laid before him. Metaphysics, as here represented, is the only science which admits of completion — and with little labour, if it is united, in a short time; so that nothing will be left to future generations except the task of illustrating and applying it didactically. For this science is nothing more than the inventory of all that is given us by pure reason, systematically arranged. Nothing can escape our notice; for what reason produces from itself cannot lie concealed, but must be brought to the light by reason itself, so soon as we have discovered the common principle of the ideas we seek. The perfect unity of this kind of cognitions, which are based upon pure conceptions, and uninfluenced by any empirical element, or any peculiar intuition leading to determinate experience, renders this completeness not only practicable, but also necessary.
Tecum
