KANT, IMMANUM„ one of the greatest and most influential metaphysicians of all time, was the son of a saddler, of Scotch descent, and was born at Konigsberg April 22, 1724. Ile was educated at the university of his native town, and after spending some years as a private tutor, took his degree at K6nigsberg in 1775, and began to deliver prelections on logic, metaphysics, natural philosophy, and mathematics. In 1782 he was offered, but declined the chair of poetry, and in 1770 he was appointed professor of logic and metaphysics. He died Feb. 12, 1804. Kant's private life was uneventful, yet curious and almost ludicrous in its mechanical regularity. As Socrates could hardly be ininced to go beyond the walls of Athens, so Kant clung with oyster-like tenacity to the city of his birth, never leaving it during the thirty years of his professorship. lie remained a bachelor all his life. Kant was a man of unimpeachable veracity and nonor, austere, even in his principles of morality, though kindly and courteous in manner, a bold and fearless advocate of political liberty, and a firm believer in human progress. The investigations by which he achieved the reputation of a reformer in philosophy. refer not so much to particular sections or problems of that science, as to its principles and limits. The central point of his systam is found in the proposition, that before anything can be determined concerning the objects of cognition, the faculty of cognition itself, and the sources of knowledge lying therein, must be subjected to a critical examination. Locke's psychology, indeed, at an earlier period in European spec ulation, bad shown a similar tendency; but before Kant, no thinker had definitely grasped the conception of a critical philosophy, and Kant himself was led to it not so much by Locke, as by Hume's acute skepticism in regard to the objective validity of our ideas, especially of the very important idea of causality. The Kantian criticism had a twofold aim: first, to separate the necessary and universal in cognition from the merely empirical (i. e., from the knowledge we derive through the senses); second, to determine the limits of cognition.
In regard to the former of these, it is of importance to observe that Kant did not subject the old psychological doctrine of "faculties" to any analysis, but attributed to each of these—viz., to the faculties of sense, understanding, judgment, and reason— certain innate a priori forms, conceptions, and functions, which, as constituting the necessary conditions of any experience whatever, possessed, on account of their sub jective necessity, a universal subjective validity. Thus, in the sense, as the faculty receptive of external impressions, there must lie, according to Kant, the forms of space and time; in the understanding, as the faculty by which the manifold in appearance is combined in the unity of conception, in the categories; in the reason, as the faculty of principles, the ideas of the unconditioned and the absolute; in the judgment, in as far as it is not merely subsumtive, but also reflective, the conception of design or con formity to the purpose in view; finally, in the will or the practical reason, the categorical imperative of the moral law.
In regard to the latter aim of the Kantian criticism—viz., to determine the limits of threoretical knowledge —the efforts of Kant go to show that universal forms, existent priori in the human mind, can afford knowledge only under the condition that the objects which they cognize are presented by experience; while for the determining of what lies beyond the limits of experience. they are merely empty forms, by which something indeed is thought, but nothing known. Even within the limits of experience itself, we are cognizant, according to Kant, through theforms of the sense and of the understanding, not of things as they are in themselves, but only as they appear; hence the opposition between nountena and placnomena. But when we try to transcend those limits and to ascertain the intelligible basis of the phenomenal world by the forms of the sense and the categories, the reason becomes entangled in an unavoidable dialectic for which there is no objective, but only a critical solution. The objects of this dialec tic, the carrying out of which constitutes an essential and leading part of the Critique of the Pure Reason, are the soul, the world, and God; and in relation to the cosmological conceptions in particular (viz., of the beginning and end of the world, of the unity or non-unity of the ultimate particles of things, of causality through freedom or through the necessity of nature), the reason is involved in a series of self-contradictions (in the Kantian technology, antinomies). The result, according to Kant, of the critical exam ination of all claims to a knowledge transcending experience in the regions of rational or speculative psychology, cosmology, and theology, is the necessity for abandoning the hope of attaining such. The idea (native to the reason) of the unconditioned is allowed to possess a regulative, not a constitutive value; that is to say, it is a principle necessary for the extension of our Inquiries beyond the fixed limits of experience, without, how ever, yielding us an extended knowledge. So far the philosophy of Kant is purely nega tive and destructive. Hamilton, Manse], and others have—in regard to the limits of the knowable—merely reiterated the arguments of the great German, while it regard to the points in which they do differ from him, as, for example, the nature of our knowledge, it is a matter of very great doubt if they are as logical and consistent as their prede cessor.