Kant, IMMANUEL, probably reputed at present the greatest of all modern philosophers, was born April 22, 1724, at Königsberg, in East Prussia, where, February 12, 1804, in the eightieth year of his age, as professor of Philosophy in the university, he died. His life, as that only of a student and a teacher, offers few vicissitudes. His parents were of humble life, but pious, respectable, good people—his father a saddler, or, more properly, a strap-maker. The tradition is that the family was of Scottish descent, and that the name was originally spelt Cant. The tradition is probably perfectly correct as regards the descent; but even Kant's grandfather is found to have had his name already spelt Kand or Kant. So far as school and college are concerned Kant may be considered as thoroughly educated; but during the whole course of these, up to his twenty-third year, he must, as regards comfort, have had but a poor and struggling time of it. For the following nine years Kant supported himself as a family tutor, the usual resource of the ordinary German student, or indeed of the poor ambitious student anywhere. Becoming doctor of philosophy in 1755, he qualified himself in the same year as a privatim docens, and, as such, he remained for fifteen years what we would call a private lecturer, though in connection with the university. Not till 1770, when he was forty-six years of age, did Kant become an ordinary professor there (about four years before that he had been promoted to a sub-librarianship, with an annual dole of some eleven pounds sterling). For nearly fifty years, then, we may say that Kant was a teacher of philosophy at Königsberg—a very general one, for he had to embrace in his lectures mathematics, physics, logic, metaphysics, natural theology, anthropology, physical geography, and, more still, Philosophical Encyclopædia, to say nothing of pyrotechnics and the art of fortification! There can be no doubt that Kant was acceptable as a teacher, and that his lectures were well attended. We have an interesting testimony from Herder to that effect. His most popular course, however, was, probably, his shallowest—that, namely, on physical geography—though not without features, as well curious in Kant's regard, as, in themselves, interesting and instructive. Only during the last twenty years of his life can it be said that Kant was famous. Before that, even the correspondence with Lambert and Mendelssohn is insufficient to show that his excellent reputation locally had ever been sensibly more general. With or without name, he was the author of a separate work or two that had made no mark; and he had occasionally written creditable papers in the public journals, principally of his own neighbourhood. He was a small, thin, somewhat rickety, bundle of bones; scarcely 5 feet high; as the Scotch say, an auld-furrant little body; honest, truth-speaking, perfectly well conducted, though not remarkable for his attendance in church; kindly and gracious, and, in his own slender, pedantic-easy way, sufficiently hospitable; but, as evinced by the modest request he refused to the sorely-straitened Fichte, with a tight enough grip on his own little savings.
The writings of Kant can be respectively assigned to three periods, according as they precede, follow, or belong to the dates of his three great Kritiken (Critiques). Of these the first is the critical date, 1781; and of the whole period that precedes it the writings are, letters included, some thirty in number. Now, let them be as they may, it is not perhaps improbable that, had Kant died the author of these writings only, both he and they would have been long ago forgotten. Neither his Thoughts on the True Estimate of Living Forces; nor his General Natural History and Theory of the Heavens, nor his Dreams of a Visionary illustrated by Dreams of Metaphysics, nor even his Latin dissertation De Mundi Sensibilis atque Intelligibilis Forma et Principiis, would have availed, it may be, to operate a diversion whether for works or workman. There is, of course, in one of the smaller papers, the hint on Kant's part that the opposing course of the tides is possibly acting in retardation of the rotatory motion of the earth; but, otherwise, the four essays named form all that is of any veritable importance in the first literary period of Kant. Not but that, generally, all through this period, there is evidence of much information and much intelligent curiosity on the part of an earnestly-thinking nature that has already attained to a certain largeness and freedom of scope. The Thoughts on the True Estimate of Living Forces was Kant's first publication, and is sufficiently creditable to a young man of twenty-three, though on a question that at that moment had been for some time already authoritatively settled. It is, however, difficult to find in it either the comprehensive inaugural programme of his idolaters, or even the prophetic excellences of his more moderate admirers. The Theory of the Heavens was published in 1755; and as regards the suggestion of a nebular hypothesis in that reference Kant deservedly claimed for himself the priority whether we look to Herschel or Laplace. Here, too, nevertheless, Kant only met with his usual bad luck for long. The little anonymous booklet of two hundred pages attracted no attention, not even that of the king, to whom it was dedicated. It may be attributed to Kant as a merit that, at this early date, he speaks of the possibility of there being planets in existence beyond Saturn, as there is to be found in the Physical Geography a similar conjecture as regards the existence of what are now called the asteroids. But in the latter reference Kant was not the first; while his suggestion in the former was an inspiration from an idea of his own in regard to comets. What, he asked himself, if, out and beyond Saturn, there were planets in paths increasingly eccentric which, as it were, would tend on the whole to make comets of planets! It is but just to note that, a year before its publication, the Theory of the Heavens had been already announced in the essay that concerns the earth's rotation. When one thinks of what speculations must have occupied at this time the mind of Kant, one must acknowledge that all this speaks volumes for the industrious inquiries and the ardent and original reflections of this young man of thirty.
Published in 1766, Kant's Dreams of a Visionary is a rather remarkable paper. Kant, all his life, at least longed to believe in the immortality of the soul and the actuality in existence of a world of spirits. He was very much impressed, accordingly, by all those stories in regard to the supernatural intuitions of Swedenborg, so much so, indeed, that he had actually bought, at the enormous expense of seven pounds sterling, the eight quarto volumes of the Arcana Cælestia. And it is in consequence of his reading in these volumes that he is led to write, half-seriously and half-ashamed, this little, for him exceptional, paper, that is, however, only in the air. Not but that there are, in all probability, signs to be detected in it of that study of Hume at last that led in the end to what has determined itself as his proper work and as his proper worth. These, however, are but obscure and semi-articulate hints, and can hardly be regarded as sufficient to justify the editors of Kant in characterising this writing as 'announcement of his greater enterprises.' The Dissertatio de Mundi Sensibilis atque Intelligibilis Forma et Principiis, published in 1770, is really the first of these, his critical endeavours. It professes to speak of the form and principles of both of the worlds to which we may be said to belong; and it certainly succeeds to its own wish in regard to one of them. For the world of the senses, namely, it does find, before experience, and in anticipation of experience, actual elements of experience that are not due to experience at all, perceptions of things that are not due to the perception of things, but only to the mind itself, only, as it were, to projections from within that throw themselves without, and stand around without. These are Time and Space, which, original or native to the faculty itself, are the a priori forms of perceptive sense. That, at least, is the conclusion of Kant; and, in that regard, he is now about as complete in the Dissertation as he was eleven years afterwards in the Critique. A similar completeness does not follow him at present, however, in respect to the other or intelligible world, the world of ideas, of the intellect, the name of which also runs in the title. Probably no one reads this Latin work in these days; but if any one attempts it, most assuredly he will find himself, in regard to what of the intelligible world he is to understand he has learned from it, only exasperated. It is only possible to suppose of Kant here, that, having succeeded to his mind in the discovery of a priori forms of sense, he can as yet only search and search, and find himself vaguely and variously bogged, in a similar attempt with reference to the a priori principles of the understanding, the intellect. For success in that respect he had still to wait for the coming into his mind of the idea of school-logic and the forms of the syllogism.
That was the triumph of the great work of 1781, the Critique of Pure Reason. We know that what led to the whole work of Kant was the endeavour on his part to find in the proposition of causality that apodictic necessity, and that rationale of it, which Hume, as against his own solution of custom, habit, challenged from philosophy and the world at large. Every change must have a cause. Yes, said Hume, but such an affair as change can only be known by experience; without experience it would be unknown. Consequently, then, it is but a fact of experience, and, like every other such fact, we know that it is, but not that it must be. The necessity we attribute to its appearance is only a necessity of custom. On the contrary, says Kant, we really do attribute to any appearance of change a perfect certainty of necessity, a necessity absolute, a necessity, not a dot or a jot, not one iota less apodictic than we attribute to any proposition, to any axiom of the mathematics. That the shortest line is the straight line—our conviction in that respect is not more fixed, assured, immovable, than our conviction that every effect, every change, must have a cause. And so far, no doubt, Kant was right. But what, then, further, of the reason of this necessity, the rationale of it, the explanation of it? Seeing that the proposition of causality is really an inferential proposition—a proposition with a conclusion, as it were, from premises—one would have thought it natural on the part of Kant to turn, in the first place, to the consideration of reason and reasoning rather than to the consideration of actual perception and sense. But, probably, as has just been named, it was the suggestion of mathematics that led to this. To explain the necessity of mathematics might be to explain also the necessity of causality. We can leave Kant's consequent proceedings to be pictured here; it is not difficult to realise how he came to his conclusion and to his belief in it. A mathematical truth depended just on the fact of perception; but, inasmuch, again, as a mathematical truth was an apodictic truth, the perception on which it depended could not be a perception of experience. Such perception could not be a posteriori; it must be a perception absolutely independent of experience; a perception, consequently, then, special, proper, and peculiar; a perception sui generis—a perception a priori! But how could that be? Why, only by space, which was the source and the seat, and, so to speak, the blackboard and tablet of mathematics, being itself a priori. But if space were a priori, so would time be. As we have seen from the Dissertation, this of a priori perception, was probably Kant's first acquisition and conquest—towards the rationale he sought. Evidently, however, it was still inadequate to the want. Time and space might be a priori, but change, a mere experience of special sense, could not lie there. Could we not add from the intellect an inferential a priori form, which, availing itself of the a priori perceptive form, might, in combination with it, give birth to an a priori schema in supply of the entire virtue of necessity to every actual instance of causality that could possibly emerge? It was here now that the suggestion of logic gave to Kant his whole tree of Categories as syntheses in correspondence with the analyses of the functions of Judgment. Judgments, propositions, were universal, particular, singular; affirmative, negative, infinite; categorical, hypothetical, disjunctive; problematic, assertoric, apodictic. So far, what was concerned was in its nature analytic; but if we supposed an equal number of synthetic functions, then under the same four general rubrics of Quantity, Quality, Relation, and Modality, we should have the twelve correspondent categories of unity, multitude, allness; reality, negation, limitation; substance, causality, reciprocity; possibility, actuality, necessity. It is impossible to follow Kant here in the working-out of all that; but it is really enough to understand as much.
These categories now were constitutive: they actually entered into the composition and constitution of things as these presented themselves for the perception of sense. That is, as acting on the a priori perceptive matter, or manifold of space and time, they (the categories) gave rise to a pure or a priori perceptive-intellectual schema that, combining with the sensations of sense as these came into consciousness (from whence they might), produced, in projection around us, this ruled and regulated, orderly, intelligible universe, in which the necessity due to the categories was the very source of law. To these constitutive materials there were added, regulatively, the three Ideas. Determined by the Category of Relation in the three forms which are found under it, there are, generically, three forms also of the logical syllogism, applicable respectively to the unconditioned of the categorical synthesis in a subject, of the hypothetical synthesis of the terms of a series, and of the disjunctive synthesis of parts in a system. And these results, otherwise named, are the objects of psychology, cosmology, and theology, or the soul, the world, and God. These, however, are but ideas—only centres, as it were, for further simplification and regulation among the categories themselves. It is for the Critique of Practical Reason now to come in and extend at least the conviction of existence to these transcendental objects of soul, world, God; and what supplies authority and fulcrum to this critique in this is the categorical imperative—the fact of the practical ego possessing a categorical imperative in determination of its own will. Considering that the ego, theoretically, was declared to be no more than an idea—no more, so to speak, than a mere logical dot on a mere logical i—it is hard to understand how, practically, it can rise at once into such throne of an autocrat. But this is certain: it is for his practical critique that Kant deserves all our heartiest praise. So much has Kant what he writes at heart here that all seems to issue at once from within him in a single breath. No purer, no more living morality, has ever been professionally produced by philosopher than glows in the Ethics of Kant.
It would appear that when Kant had accomplished as much as this, he turned back to look upon it and reflect. I have found, he seems to have said to himself, my Categories in the a priori of the understanding, and my Ideas in the a priori of the reason. That is enough for our theoretical and practical interests; but what of our only other generic interest that remains—what of our interest that we call æsthetic? That refers to a function on our part that seems intermediate between the other two—the theoretical and practical functions. But these depending respectively on the Understanding and Reason, is there nothing similarly intermediate between these two again? Yes, there is Judgment. And so it was that Kant was led to his third great critique, the subjects of which were generally, to say so, the products of Art—i.e. Beauty, Sublimity, Design. Beauty originated in the harmony of our own two constitutive elements—sense on the one side and intellect on the other. Sublimity was the feeling of the exaltation in mind above every menace and magnitude of sense. Since design, so to speak, meant evident arrangement by another hand as though from without, it was impossible to give it place, on such terms, in our world; which, in the contributions of special sense (mere sensations), in time and space, in the categories, the ideas, and all else, was only a world within—a world, indeed, all but wholly of our own construction within. We could only say of it (design), in such circumstances, that we ourselves were so fashioned that we could only see into our world as though it were the product of an understanding.
Among the remaining works of Kant there are some of considerable bulk and some interest, but little value—at least so far as originality is concerned. Such are the Anthropologie and the Logik. The Streit der Facultäten, Rechtslehre, Tugendlehre, Religion innerhalb der Grenzen der blossen Vernunft—all are well worth reading, and will greatly help to a general understanding of their author. In that latter respect the Prolegomena, the criticism of Eberhard, and the essay on the Progress of Metaphysics since Leibnitz and Wolff, are specially to be signalised, and may even be named indispensable. The essay in the philosophy of nature, Metaphysische Anfangsgründe der Naturwissenschaft, cannot well be neglected, and still less, perhaps, various little essays in natural history. Even the critique of Herder will be found good, and, just on the whole, it may be said that no work on Kant's part, however small, should, if belonging to the middle or concluding period, fail to be read. The little essays that bear on natural history, for example, however unimportant they may appear, contain more than one declaration that is of interest, in so far as Kant, though averse, probably, to the dogma of direct creation, has yet, in his perception of the existence of ideas, and of actual concert on ideas, in nature, never a thought of even the suggestion of a mechanical evolution through chance.
It is impossible to overrate the enormous impulse which Kant has been the means of giving to the study of philosophy, both in Germany and everywhere else (as well in America and the East as in Europe). Quite a host of names, besides those of Jacobi, Fichte, Schelling, Hegel, Herbart, Krause, Schopenhauer, Schleiermacher, might be mentioned in this connection. It is not quite certain, however, that Kant's work will prove to have been more in the end than one principally of suggestion. We know not but that, if all that monstrous gaunt machinery—æsthetic, analytic, what not—had been offered precisely as the machinery proper for the production of the necessity in causality—we know not but that, if all that monstrous gaunt machinery (time and space themselves shut up within it) had been seriously offered, for that purpose, from Germany, and in the time of Hume—we know not but that it might have been received with something more unequivocal than a smile! But be that as it may, and assuming the constructions of Kant to prove in themselves neither a solution for the problem of the universe, nor yet for the problem of causality, we have still to bear in mind what suggestion in his regard means. Apart all consideration of his followers, the truth is that it is to Kant we owe—with discount only of all necessary historical addition—our entire metaphysical material at present. Really, whatever metal of speculation is anywhere turned now, the ore of it was Kant's. The Critique of Pure Reason, if not precisely to be named a liberal education, very certainly is, has been, and will remain, an education in philosophy.
BIBLIOGRAPHY.—A complete bibliography of Kant would cover pages, and is beyond the proportions of this publication. We name only what will probably be found most useful. Of the whole works four editions may be mentioned, those of Rosenkranz and Schubert (Leip. 1838-42); of Hartenstein (Leip. 1838-39); again of Hartenstein (Leip. 1867-69); of V. Kirchmann (Leip. 1868, and further). Benno Erdmann (Leip. 1880) edits a notable edition of the Critique of Pure Reason, and Reclam, of Leipzig, publishes a very useful small edition of the same work, edited by Kehrback. Of translations of the Critique of Pure Reason into English there are those of Meiklejohn and Max Müller, and the text-book to Kant of Stirling. Abbott and Bax also translate into English important works of Kant, the one the Ethics and the other the Prolegomena.
Of writers generally in regard to the philosophy of Kant the following may be mentioned—German: Hegel, Michelet, Erdmann, Ueberweg, Schwegler, Kuno Fischer, I. H. Fichte, Chalybaeus, Ulrici, Biedermann, Weigelt, Fortlage, Ritter, Kirchner, Drechsler, Liepmann, Haym, Oischinger, Schaarschmidt, Zeller, Drobisch, Steffen, Windelband, V. Hartmann, Krause, Volkelt, Hölder, Vaihinger, Staudinger, Lasswitz, Spicker, Paulsen, Thiele, Cohen, Riehl, Stadler, Thilo, Dühring, Sigwart, Falckenberg. French: Ott, Willm, Wooquier, Foucher de Careil, Barchou de Penhoën, Saintes, Maurial, Saisset, Villers, Vacherot, Cousin. Italian: Galuppi, Testa, Spaventa, Lilla, Cesca. English: Nitsch, Willich, Hodgson, Laurie, Montgomery, Bolton, Ingleby, Adamson, Seth, Hastie, Bowen, Morris, Porter, Caird, Watson, Mahaffy, Maguire, Monck, Green, Wallace, Mansel, Lewes, Nakashima, A. J. Balfour.