In order that we may rise to free action, opposition is needed, and this we get in the spatial-temporal world of phenomena, or nature, which the ego creates for itself in order to have resistance to overcome. Fichte conceives of nature as "the material of our duty," as the obstacle against which the ego can exercise its freedom. There could be no free action without something to act upon, and there could be no purposive action without a world in which everything happens according to law; and such a causal world we have in our phenomenal order, which is the product of the absolute spiritual principle. By the ego Fichte did not mean the subjective ego, the particular individual self with all its idiosyncrasies, but the universal ego, the reason that manifests itself in all conscious individuals as universal and necessary truth. In his earlier period he did not define his thought very carefully, but in time the absolute ego came to be conceived as the principle of all life and consciousness, as universal life, and ultimately identified with God. His philosophy is, therefore, not subjective idealism, although it was so misinterpreted, but objective idealism; nature is not the creation of the particular individual ego, but the phenomenal expression, or reflection, in the subject of the universal spiritual principle.
Upon such an idealistic world-view Fichte based the ethical teachings through which he exercised a lasting influence upon the German people and the history of human thought. The universal ego is a moral ego, an ego with an ethical purpose, that realizes itself in nature and in man; it is, therefore, the vocation of man to obey the voice of duty and to free himself from the bondage of nature, to be a person, not a thing, to coöperate in the realization of the eternal purpose which is working itself out in the history of humanity, to sacrifice himself for the ideal of freedom. Every individual has his particular place in which to labor for the social whole; how to do it, his conscience will tell him without fail. And so, too, the German people has its peculiar place in civilization, its unique contribution to make in the struggle of the human race for the development of free personality. It is Germany's mission to regain its nationality, in order that it may take the philosophical leadership in the work of civilization, and to establish a State based upon personal liberty, a veritable kingdom of justice, such as has never appeared on earth, which shall realize freedom based upon the equality of all who bear the human form.
The Fichtean philosophy holds the mirror up to its age. With the Enlightenment it glorifies reason, the free personality, nationality, humanity, civilization, and progress; in this regard it expresses the spirit of all modern philosophy. It goes beyond the Aufklärung in emphasizing the living, moving, developing nature of reality; for it, life and consciousness constitute the essence of things, and universal life reveals itself in a progressive history of mankind. Moreover, the dynamic spiritual process cannot be comprehended by conceptual thought, by the categories of a rationalistic science and philosophy, but only by itself, by the living experience of a free agent. In the categorical imperative, and not in logical reasonings, the individual becomes aware of his destiny; in the sense of duty, the love of truth, loyalty to country, respect for the rights of man, and reverence for ideals, spirit speaks to spirit and man glimpses the eternal.
Among the elements in this idealism that appealed to the Romanticists were its anti-intellectualism, its intuition, the high value it placed upon the personality, its historical viewpoint, and its faith in the uniqueness of German culture. They welcomed the Wissenschaftslehre as a valuable ally, and exaggerated those features of it which seemed to chime with their own views. The ego which Fichte conceives as universal reason becomes for them the subjective empirical self, the unique personality, in which the unconscious, spontaneous, impulsive, instinctive phase constitutes the original element, the more extravagant among them transforming the rational moral ego into a romantic ego, an ego full of mystery and caprice, and even a lawless ego. Such an ego is read into nature; for, filled with occult magic forces, nature can be understood only by the sympathetic divining insight of the poetic genius. And so, too, authority and tradition, as representing the instinctive and historical side of social life, come into their own again.
Fichte's chief interest was centred upon the ego; nature he regarded as a product of the absolute ego in the individual consciousness, intended as a necessary obstacle for the free will. Without opposition the self cannot act; without overcoming resistance it cannot become free. In order to make free action possible, to enable the ego to realize its ends, nature must be what it is, an order ruled by the iron law of causality. This cheerless conception of naturewhich, however, was not Fichte's last word on the subject, since he afterward came to conceive it as the revelation of universal life, or the expression of a pantheistic Goddid not attract Romanticism. It was Schelling, the erstwhile follower and admirer of Fichte, who turned his attention to the philosophy of nature and so more thoroughly satisfied the romantic yearnings of the age.