From what has been said, we can see the universal standpoint of the Theory of Science; the Ego is made a principle, and from the Ego every thing else is sought to be derived. It hardly needs to be remarked, that by this Ego we are to understand, not any individual, but the universal Ego, the universal rationality. The Ego and the individual, the pure and the empirical Ego, are wholly different conceptions. We have still the following preface to make concerning the form of the Theory of Science. A theory of science, according to Fichte, must posit some supreme principle, from which every other must be derived. This supreme principle must be absolutely, and through itself, certain. If our human knowledge should be any thing but fragmentary, there must be such a supreme principle. But now, since such a principle does not admit of proof, every thing depends upon giving it a trial. Its test and demonstration can only be thus gained, viz., if we find a principle to which all science may be referred, then is this shown to be a fundamental principle. But besides the first fundamental principle, there are yet two others to be considered, the one of which is unconditioned as to its content, but as to its form, conditioned through and derived from the first fundamental principle; the other the reverse. The relation of these three principles to each other is, in fine, this, viz., that the second stands opposed to the first, while a third is the product of the two. Hence, according to this plan, the first absolute principle starts from the Ego, the second opposes to the Ego a thing or a non-Ego, and the third brings forward the Ego again in reaction against the thing or the non-Ego. This method of Fichte (thesis,—antithesis,—synthesis) is the same as Hegel subsequently adopted, and applied to the whole system of philosophy, a union of the synthetical and analytical methods. We start with a fundamental synthesis, which we analyze to produce its antitheses, in order to unite these antitheses again through a second synthesis. But in making this second synthesis, our analysis discovers still farther antitheses, which obliges us therefore to find another synthesis, and so onward in the process, till we come at length to antitheses which can no longer be perfectly but only approximately connected. We stand now upon the threshold of the _Theory of Science_. It is divided into three parts. (1) General principles of a theory of science. (2) Principles of theoretical knowledge. (3) Principles of practical science. As has already been said, there are three _supreme_ fundamental principles, one absolutely unconditioned, and two relatively unconditioned.