JA'COBI, FREDERICK HENRY, a philosophical writer of Ger many, was bora at Dusseldorf, in 1743. He was distinguished, not so much as the author of a peculiar system of philosophy, as for the critical acumen and forcible eloquence with which he detected and exposed the incoherences and defects of the prevailing systems, of which he traced the inevitable consequences with great rigour and sagacity. Originally educated for a mercantile profession, Jacobi united the pursuits of literature to those of commerce until his appointmeut as councillor in the Hofkammer of his native city, which he obtained by the good offices of the Count von Golstein, enabled him to indulge his natural tastes and inclination by devoting his whole time and attention to literature. In this new career he sought to combine poetry with philosophy, and hie earliest publication was a philosophical poem, entitled 'Friendship and Love,' which first appeared in 1777, but was republished two years afterwards under the simpler title of Weide mar.' In this year Jacobi was invited to Munich, and appointed geheimrath, in which situation he evinced the honesty and independ ence of his character by exposing publicly the injurious tendency and imprudence of the Bavarian system of finance. lu 1781 he commenced an able controversy with Mendelssohn, by his work On the Doctrine of Spinosa,' which he further prosecuted in his Observations on Mendelssohn's Apology for the Doctrine of Spinosa.' By the essay, entitled 'David Hume, or Idealism and Realism,' he provoked the hostility of the followers of Kant, and that of the admirers of Fichte by his Sendschreiben an Fichte,' whose respect however, as well as that of most of his controversial opponents, he secured by the known sincerity of hie character and opinions. When the troubles arising out of the French revolution extended to Germany, Jacobi retired to Holstein, whence he removed successively to Wandsbeck and Ham burg ; from the latter he was called, iu 1804, to Munich, to assist in the formation of the new Academy of Sciences, of which he was appointed president, in 1807. This dignity Jacobi resigned upon attaining bis seventieth year, but was allowed to retain the salary and emoluments. Shortly previously his work 'On Divine Things and on Revelation' (Leipz. 1811) had involved him in • bitter with Schelling, who, in his answer, which bore the title ' Memorial to the Work on Divine Thing•,' professed to give the real position of Jacobi with respect to soleoce and theism, or, io other words, to philo sophy and religion, and generally to literature. Notwithstanding the unfavourable estimate which this great phileeopher drew therein of the literary and philosophical merits of Jacobi, he still maintains a high rank among sincere and honest inquirers after truth; and oven if, exclusively occupied with detached speculations, he rather prepared than established a system of philosophy, the profoundness and origi nality of his views have furnished materials of which more systematic minds have not scrupled to avail themselves for the construction of their own theories.
As a poet, in which capacity he was greatly inferior to his brother (John George), Jacobi was a reflective rather than an imaginative thinker. His poetical merits are chiefly confined to vividness of de
scription and to boldness of style. His philosophical writings, notwith standing the want of all scientific method, are remarkable for the beauty of the exposition, which is conveyed in a form at once vigorous and harmonious. His views of philosophy, as far as they can bo gathered from his scattered and occasional compositions on the subject, were rather of a sceptical than of • dogmatical character, and he denied the possibility of certainty in human knowledge. lie maintained that all demonstrative systems must necessarily lead to fatalism, which however is irreconcileable with man's consciousness of the freedom of his rational nature. The general system of nature indeed, and man himself, so far as he is a part of that system, is pure mechanism; but in man there is unquestionably an energy which transcends and is superior to sense, or that faculty which is bound up with and regu lated by the laws of nature. This higher energy is liberty, or reason, and consequently sense and reason distinguish to man two distinct spheres of his activity—the sensible or visible world, and the invisible or intelligible. The existence of these worlds no more admits of demonstrative proof than that of sense and reason themselves. Now sense and reason are the supreme and ultimate principles of all intel lectual operations, and as such legitimate them, while they themselves do not receive their legitimisation from aught else ; and the existence of sense and reason necessarily implies the existence of sensible and intelligible objects about which they are conversant. But this existing system of things cannot have originally proceeded either from nature or from man's intellect or reason, for both nature and the human mind are finite and conditionate, and there must bo something infinite and unconditionate, superior to and independent both of nature and man, to be the source and principle of all things. This being is God. Now as man's liberty consists in his personality or absolute individuality, for this constitutes his proper essence, while the mechanism of nature is hereby distinguished from man, that none of its members are indi vidual of character, therefore that which is superior both to nature and to man must be perfectly and supremely individual ; God conse quently is one only, and strictly personal. Moreover, as the ground of all subsistence, he cannot be without subsistence; and as the prin ciple of reason, he cannot be irrational. Of the existence of this divine intelligence however all direct proof is as impossible as a demonstration of existence simply. Generally indeed nothing can be known except upon testimony, and whatever rests on testimony is not certainty but faith, and such a faith or belief, when its object is the existence of a good and supreme being, is religion.
Jacobi died at Munich on the 10th of March 1810. His complete works have been published in 6 vols., Leipzig, 1819.20.