In reading even the best treatises on education written in former times, one becomes aware of certain changes that have come over educational theory. The two great reformers of educational theory before the nineteenth century were Locke and Rousseau. Both deserved their reputation, for both repudiated many errors which were wide-spread when they wrote. But neither went as far in his own direction as almost all modern educationists go. Both, for example, belong to the tendency which led to liberalism and democracy; yet both consider only the education of an aristocratic boy, to which one man’s whole time is devoted. However excellent might be the results of such a system, no man with a modern outlook would give it serious consideration, because it is arithmetically impossible for every child to absorb the whole time of an adult tutor. The system is therefore one which can only be employed by a privileged caste; in a just world, its existence would be impossible. The modern man, though he may seek special advantages for his own children in practice, does not consider the theoretical problem solved except by some method of education which could be open to all, or at least to all whose capacities render them capable of profiting by it. I do not mean that the well-to-do should, here and now, forego educational opportunities which, in the existing world, are not open to all. To do that would be to sacrifice civilization to justice. What I do mean is that the educational system we must aim at producing in the future is one which gives to every boy and girl an opportunity for the best that exists. The ideal system of education must be democratic, although that ideal is not immediately attainable. This, I think, would, nowadays, be pretty generally conceded. In this sense, I shall keep democracy in view. Whatever I shall advocate will be capable of being universal, though the individual should not meantime sacrifice his children to the badness of what is common, if he has the intelligence and the opportunity to secure something better. Even this very attenuated form of democratic principle is absent from the treatises of Locke and Rousseau. Although the latter was a disbeliever in aristocracy, he never perceived the implications of his disbelief where education was concerned.