However that may be, the type of education that presupposes a certain ideal of knowledge previously constituted and ready to be imparted by the teacher to the pupil in conformity with some suitable method, must follow a method, a unique one--the method of science, and therefore of the teacher, and therefore also of the pupil, whether the latter is capable of it or not. For it is tacitly assumed that science==method; science==teacher; science==pupil. On the strength of these equations the common term "science" should suffice to identify the first method, which is the one of science in itself, with the last, which is the method of science to be mastered by the pupil. But the above series of equations is false, because, admitting the first, the one namely on the basis of which we are now discussing, neither the second nor the third is possible without passing from realistic to idealistic science,--two very different things, as I have shown. Even if we leave the teacher out of consideration, we shall have to remember that the pupil learns a science by making it his own,--a fallible science, which he may understand up to a certain point and no further. It will be one of the many sciences which have no one given method, but many of them, and the pupil can only avoid appropriating, individualising, subjectivising science by following that way which is very broad, very easy, and, alas, only too well beaten,--the royal road of non-learning, which is diligently upkept by all the schools which have to teach precise, well-defined science, and have a pre-established method by which to teach it. But, it might be objected, if science, realistically conceived, is a fictitious entity in no way corresponding to reality, how is it possible to have a method which by its uniqueness and definiteness effectively corresponds to the unalterable unity of this non-existent science? And what teacher would ever arbitrarily impose on his students such an abstract and mechanical method? This is true enough; but man learns to compromise with all deities, Science included. This divinity, in order somehow to exist, must assume a few human traits without however renouncing her divine prerogatives. The fact that Apollo held no communion with the Pythian priestess did not remove the oracular sanctity from the Delphic response. For man knows no deity other than the one which he is capable of conceiving with his soul, just as he knows no other red besides the one which he sees with his own eyes.