“ Kant and Fichte together became the most potent philosophic influences on European thought in the 19th century, because their emphasis was on man. They made man believe in himself and his mission. They fostered liberty and reform, and even radicalism. They almost avenged man on the astronomers, who had shown that the world is not made for earth, and therefore not for man. Kant half asserted, and Fichte wholly, that Nature is man’s own construction. ”

“ Spinozism, however, though it tramples down the barrier between body and soul, is not yet metaphysical idealism, because it does not reduce extension to thought, but only says that the same substance is at once extended and thinking—a position more akin to materialism. ”

“ Hume saw that in making all the objects of perception ideas Berkeley had given as little reason for inferring substantial souls as substantial bodies. He therefore concluded that all we know from the data of psychological idealism is impressions or sensations, ideas, and associations of ideas, making us believe without proof in substances and causes, together with “a certain unknown, inexplicable something as the cause of our preceptions.” ”

“ The Kritik and the Wissenschaftslehre belonged to the revolutionary epoch of the “Rights of Man,” and produced as great a revolution in thought as the French Revolution did in fact. Instead of the old belief that God made the world for man, philosophers began to fall into the pleasing dream, I am everything, and everything is I—and even I am God. ”

“ According to one alternative, which consistently flowed from the psychological idealism of Descartes, as well as from his own monadism, he suggested that bodies are real phenomena; phenomena, because they are aggregates of monads, which derive their unity only from appearing together to our perceptions; real phenomena well founded, because they result from real monads. In support of this view, he said that bodies are not substances, though substantiata; that their apparent motion and resistance are results of the passions of their monads ”

“ Psychological idealism assumes without proof that we perceive nothing but mental objects, and metaphysical idealism draws the logical but hypothetical conclusion that all we can know from these mental objects of sense is mental objects of knowledge. ”

“ In expanding Kant’s act of synthesis till it absorbed the inner sense and the innermost soul, he started the modern paradox that soul is not substance, but subject or activity, a paradox which has been gradually handed down from Schelling and Hegel to Fechner, and from Fechner to Paulsen and Wundt. Meanwhile, through holding with Kant that man is not God, but a free spirit, whose destiny it is to use his intelligence as a means to his duty, he is still the resort of many who vindicate man’s independence, freedom, conscience, and power of using nature for his moral purposes, e.g. ”

“ As to existence, Kant’s position is the wholly illogical one that, though all known things are phenomena, there are things in themselves, or noumena; things which are said to cause sensations of outer sense and to receive sensations of inner sense, though they are beyond the category of causality which is defined as one of the notions uniting phenomena; and things which are assumed to exist and have these causal attributes, though declared unknowable by any logical use of reason, because logical reason is limited by the mental matter and form of experience to phenomena ”

“ From this point of view he believed that the real unity of a body is a vinculum substantiale, which gives it its real continuity and is the principle of its actions; that its primary matter is its own principle of resistance; and that it has not only this passive, but also an active, power of its own. He suggested that this theory of the substantial unity of a body might explain transubstantiation, by supposing that, while the monads and phenomena of bread remain, the vinculum substantiale of the body of Christ is substituted. ”

“ According to Kant, the objective is valid for all consciousnesses; according to Fichte it is valid for one consciousness. Here he was for the first time grappling with a fundamental difficulty in metaphysical idealism which is absent from realism, namely, the difficulty of explaining the identity of a thing, e.g. the sun. As long as even the meagre realism of the Kantian thing in itself is maintained, the account of there being one sun is simply that one thing causes different phenomena in different minds. ”

“ Even the Cartesian school, as it came more and more to feel the difficulty of explaining the interaction of body and mind, and, indeed, any efficient causation whatever, gradually tended to the hypothesis that the real cause is God, who, on the occasion of changes in body, causes corresponding changes in mind, and vice versa. ”

“ Hence in his Philosophical Journal in 1798 Fichte prefaced a sceptical essay of Forberg by an essay of his own, in which he used the famous words, “The living moral order is God; we need no other God, and can comprehend no other.” Having, however, in consequence, lost his professorship at Jena, he gradually altered his views, until at length he decided that God is not mere moral order, but also reason and will, yet without consciousness and personality; that not mankind but God is the absolute ”

“ On the other hand, under the influence of the mechanics of his day, which had hardly distinguished between inertia, or the inability of a body to change itself, and resistance or the ability of bodies to oppose one another, he concluded that, as inertia is passive, so is resistance, and refused to recognize that in collision the mutual resistance of moving bodies is a force, or active power, of changing their movements in opposite directions. ”

“ In making the essence of mind activity and construction, in destroying the separation of theoretical and practical reason, in asserting that mind thinks things as means to ends of the will, he prepared the way for Schopenhauer and other voluntarists. ”

“ On the one hand, essentially a mathematician, he supposed that unity is indivisibility, whereas everything known to be one is merely undivided or individual, and that there must be simple because there are compound substances, although composition only requires simpler or relatively simple elements. ”

“ He forgot that he had also limited all logical use of reason, and therefore of practical reason, to phenomena, and thereby undermined the rationality not only of knowledge, but also of faith.
Fichte now set himself in the Wissenschaftslehre (1794) to make transcendental idealism into a system of metaphysical idealism without Kant’s inconsistencies and relics of realism. His point was that there are no things in themselves different from minds or acting on them; that man is no product of things; nor does his thinking arise from passive sensations Fichte. caused by things ”

“ This second position is a new form of metaphysical idealism, containing the supposition, which lies at the foundation of later German philosophy, that since understanding shapes the objects out of sensations, and since nature, as we know it, consists of such objects, “understanding, though it does not make, shapes nature,” as well as our knowledge. Known nature is a mental construction in part, according to Kant. ”