And yet, this question is not quite so difficult if we only renounce completely all preconceived notions. I have tried to elucidate and solve this question, and, without repeating those proofs, which he who wishes may read in the article, I will enunciate the results to which I was led. "The only criterion of pedagogy is freedom, the only method--experience." After fifteen years I have not changed my opinion one hair's breadth; but I consider it necessary to define with greater precision what I understand by these words, not only in respect to education in general, but also in respect to the particular question of popular education in a primary school. One hundred years ago the question what to teach and how to teach could have had no place either in Europe or with us. Education was inseparably connected with religion. To learn reading meant to learn Holy Writ. In the Mohammedan countries this relation of the rudiments and religion still persists in its full force. To learn means to learn the Koran, and, therefore, Arabic. But the moment religion ceased to be the criterion of what ought to be taught, and the school became independent of it, this question had to arise. But it did not arise because the school was not suddenly freed from its dependence on religion, but by imperceptible steps. Now it is accepted by everybody that religion cannot serve as the contents, nor as an indication of the method of education, and that education has different demands for its basis. In what do these demands consist? On what are they based? In order that these principles should be incontrovertible, it is necessary either that they be proved philosophically, incontrovertibly, or that, at least, all educated people should be agreed on them. But is it so? There can be no doubt whatsoever about this, that in philosophy have not been found those principles on which could be built up the decision of what ought to be taught, the more so since the matter itself is not an abstract, but a practical affair, which depends on an endless number of vital conditions. Still less can these principles be discovered in the common consent of all men who busy themselves with this matter, in the consent which we may take as a practical foundation, as an expression of the universal common sense. Not only in matters of popular, but even of higher education do we see a complete diversity of opinions among the best representatives of education, as, for example, in the question of classicism and realism. And yet, in spite of the absence of any foundations, we see education proceeding on its own path and on the whole being guided by only one principle, namely by freedom. There exist side by side the classical and the real school, each of which is prepared to regard itself as the only natural school, and both satisfy some want, for parents send their children to either.