KANT, kiint, I MMANUEL (1724-1804). One of the greatest and most influential German meta physicians. He was the son of a saddler, of Scotch descent, and was born at Kiinigsberg, April 22, 1724. Ile studied philosophy, mathe matics, physics, theology, and other subjects, at the university of his native town, and. after spending nine years as a private tutor in several families, took his degree at Kiinigsberg in 1755, and began to deliver lectures as privat docent, on logic, metaphysics, physics, polities, and mathematics; later he added courses on physi cal geography, anthropology, natural theology, and pedagogy, and one year he lectured on miner alogy. In 1762 he was offered the chair of poetry at KOnig.sberg, but. though in some need of the salary, he wisely declined because he was not fitted for the place. The next year he obtained a position of assistant librarian on a salary of 62 Hinters; and, though he had now become well known and greatly esteemed for his scholarship, he (lid not obtain a professorship until 1770, when he was appointed to the chair of logic and metaphysics, as an inducement to keep him in Konigsberg, now that he had received calls to Erlangen and Jena. In 1778 he had a call to Halle. which he declined, to remain at Konigsberg till his death, February 12, 1804. Kant's private life was uneventful. He was a bachelor and never traveled. He was a man of unimpeachable vera city and honor, austere in his principles of moral ity. though kindly and courteous in manner, a bold and fearless advocate of politic-al liberty, and a firm believer in human progress. He sym pathized with the American Colonies in their struggle against England, and with the French people in their revolt against monarchical abuses. As a lecturer he was popular. Herder says that his lectures were characterized by deep thought, wit, and humor. They were said to have been much more dogmatic in tone than his writings, and to have had moral and religious edification in mind as well as the imparting of information.
In philosophy he developed slowly. His views did not seem to take anything like final form till he wrote his greatest work. Kritik der reinen Vrr nunft, which was first published in 1731. By this time he hal effected in philosophy what he called a Copernican revolution. "Our suggestion." he writes, "is similar to that of Copernicus in astron omy, who, finding it impossible to explain the movements of the heavenly bodies on the supposi tion that they turned round the spectator, tried whether he might not succeed better by supposing the spectator to revolve and the stars to remain at rest. Let us make a similar experiment in metaphysics with perception. If it were really necessary for our perception to conform to the nature of objects, I do not see how we could know anything of it u priori; but if the sensible object must conform to the constitution of our faculty of perception, I see no difficulty in the matter. Perception, however, can become knowl edge only if it is related in some way to the object which it determines. Now here again I may sup pose, either that the conceptions through which 1 effect that determination conform to objects, or that objects, in other words the experience in which alone objects are known, conform to con ceptions. In the former case I fall into the same perplexity as before, and fail to explain how such conceptions can he known a priori. In the latter ease the outlook is more hopeful. For experience is itself a mode of knowledge which implies in telligence, and intelligence has a rule of its own, which must he an a priori condition of all knowledge of objects presented to it. 'l'o this rule, as expressed in a priori conceptions, all objects of experience must necessarily conform, and with it they must agree." (Preface, tr. by Watson.) This passage shows that Kant started with the assumption that there is a priori syn thetic knowledge, i.e. as he defined it, knowledge of universal and necessary truths. (See ANALYTIC JUDGMENT, and A PRIORI.) His mathematical training had taught him to regard the truths of mathematics as universal and necessary: while Hume had convinced him that any merely dog matic assumption of universality and necessity was unwarranted. His problem now was how to escape dogmatism and yet justify the making of universal synthetic propositions, such as that two and two make four. This problem he solved to his satisfaction by making the world of experi ence in part a product of the intelligence that passes judgments. Space and time are 'forms of perception.' that is, the frameworks within one of which, at least, objects must be arranged before they can be perceived. They are 'conditions of the possibility of phenomena.' This they could not be unless they were imposed upon phenomena by the percipient agent. But not only must objects be perceived, in order to l known; they must he conceived also. This act of conception is warranted only if objects, before being presented in experience, are worked into order by the same intelligence that in judgment unconditionally predicates this order of them. The forms of per ception are space and time; the order produced by intellectual spontaneity is constituted by four great principles of synthesis—quantity, quality.
relation, and modality—and each of these appears in threefold form. Hence we have twelve 'cate gories' or 'pure conceptions of the understand ing,' viz.: (1) Unity. (2) plurality. and (3) to tality: (4) reality, (5) negation, and (6) limita tion; (7) inherence and subsistence; (S) causality and dependence: and (9) community. (10) possi bility and impossibility. (11) existence and non existence. and (12) necessity and contingency. These categories are discovered by examination of the `functions of unity in judgment.' i.e. by examination of the different ways in which the mind, in judging„ predicates unity or order of the world of experience. Now the fundamental eon tention of Kant is that these categories must be principles employed in the construction of the world of experience if they are to be legitimately employed in the cognition of that world. This is the idealistic element in his system; the world we know is, in its form, a perceptual and intel lectual creation, the work of the mind. He calls this idealism transcendental. i.e. it relates only to the conditions of the possibility of knowledge; it is not transcendent. i.e. it does not relate to any existences lying behind experience, and there fore beyond the reach of knowledge. And yet, though the system is transcendental idealism, it is an empirical realism, i.e. it maintains that the real world of experience is a world really con stituted in accordance with principles which science diseovers. Thus, time is empirically real because the world use know is really a time-world. But along with this empirical realism and tran scendental idealism there goes hand in hand an agnosticism which denies the possibility of know ing anything whatever of another world of being —the world of things-in-themselves. These things in-themselves affect our sensibility and thus give rise to sensations, which fall into the forms of perception and are organized by the categories into the world of experience. But what these things-in-themselves are we can never know. If reason attempts to make any assertion with regard to them, it falls into hopeless inconsisten cies and inextricable confusions, paralogisms,and antinomies. And yet reason is ever striving to go beyond experience. The world of experience is never complete; it is a progresses and a regresses ad inlinitym. But reason craves completeness. It has ideas which find no embodiment in experi ence, because "they demand a certain complete ness which is beyond the reach of all possible empirical knowledge." But neither may these ideas he thought to find embodiment in things-in themselves, for in this case judgment would tran scend its proper experiential limits. They are not empirically or transcendentally real; but neither are they transcendentally ideal, for they are not conditions of the possibility of knowledge. Thus excluded from all these classes, Kant finds a func tion for them as regulative principles for the conduct of the understanding in its search for knowledge, telling us not to be satisfied in our attempts to reduce experience to order unless we should complete the systematization. But com plete it we never'ean. The ideas are warnings "not to regard any single determination relating to the existence of things as ultimate." But we may not substantiate the ideas by claiming that the completeness unattainable in experience is actual beyond experience. This would be tran scendental subreption: and though natural and impossible to avoid, it may be understood to be fallacious when it is seen that thus a regulative principle is changed into a constitutire principle. There are three such ideas—that of 'the absolute or unconditioned unity of the thinking subject.' that of 'the absolute unity of the series of condi tines of phenomena.' and that of 'the absolute unity of the condition of all objects of thought whatever.' These ideas, when substantiated and individualized. become the transcendental ideal, i.e. 'the idea of a totality of .reality (omnitudo rralitatis),' an 'ens realissimum,"ens 'ens summum,"ens entiuni,' all of which are epithets given by scholastic theology to God. "By such a use of the transcendental idea, however, theology oversteps limits set to it by its very nature." All traditional proofs for the being of God, which Kant reduces to three— the ontological, the cosmological and the physico theological ,proofs (see Goo) =he criticises as fal lacious: "The Supreme Being is for purely specu lative reason a mere ideal. but still a perfectly faultless ideal, which completes and crowns the whole of human knowledge. And if it should turn out that there is a moral theology, which is able to supply what is deficient in speculative theology, we should then find that transcendental theology is no longer problematic. but is indis pensable in the determination of the conception of a Supreme Being• (Watson's trans.). In his ethical works, Kant does filially arrive at such a moral theology as the final postulate of mo rality.