separated according to the different groups of his writings.[4] I. FIRST PERIOD. SCHELLING’S PROCESSION FROM FICHTE. Schelling’s starting point was Fichte, whom he decidedly followed in his earliest writings. In his essay, “_On the Possibility of a Form of Philosophy_” he shows the necessity of that supreme principle which Fichte had first propounded. In his essay, “_On the Ego_” Schelling shows that the ultimate ground of our knowledge can only lie in the Ego, and hence that every true philosophy must be idealism. If our knowledge shall possess reality, there must be one point in which ideality and reality, thought and being, can identically coincide; and if outside of our knowledge, there were something higher which conditioned it, if itself were not the highest, then it could not be absolute. Fichte regarded this essay as a commentary on his _Theory of Science_; yet it contains already indications of Schelling’s subsequent standpoint, in its expressly affirming the unity of all knowledge, the necessity that in the end all the different sciences shall become merged into one. In the “_Letters on Dogmatism and Criticism_,” 1795, Schelling combatted the notions of those Kantians who had left the critical and idealistic standpoint of their master, and fallen back again into the old dogmatism. It was also on the standpoint of Fichte that Schelling published in Niethammer’s and Fichte’s Journal, 1797-98, a series of articles, in which he gave a survey of the recent philosophical literature. Here he begins to turn his attention towards a philosophical deduction of nature, though he still remains on the standpoint of Fichte when he deduces nature wholly from the essence of the Ego. In the essay which was composed soon after, and entitled “_Ideas for a philosophy of Nature_,” 1797, and the one “_On the World-soul_,” 1798, he gradually unfolded more clearly his views. The chief points which are brought out in the two last named essays are the following: The first origin of the conception of matter springs from nature and the intuition of the human mind. The mind is the union of an unlimited and a limiting energy. If there were no limit to the mind, consciousness would be just as impossible as if the mind were totally and absolutely limited. Feeling, perception and knowledge are only conceivable, as the energy which strives for the unlimited becomes limited through its opposite, and as this latter becomes itself freed from its limitations. The actual mind or heart consists only in the antagonism of these two energies, and hence only in their ever approximate or relative unity. Just so is it in nature. Matter as such is not the first, for the forces of which it is the unity are before it. Matter is only to be apprehended as the ever becoming product of attraction and repulsion; it is not, therefore, a mere inert grossness, as we are apt to represent it, but these forces are its original. But force in the material is like something immaterial.