It is pretty generally agreed to by thoughtful educators, that in giving a child the broad foundations of education, we should aim not so much at knowledge as at capacity and _appreciation_ for it. A universal receptivity, such as Rousseau requires of Emile, is a desideratum. Scarcely a better dowry can be bestowed upon a child by education, than a desire for knowledge and an intelligent interest in all important branches of study. Herbart's many-sided interest is to strengthen and branch out from year to year during school life, and become a permanent tendency or force in later years. No school can give even an approach to full and encyclopedic knowledge, but no school is so humble that it may not throw open the doors and present many a pleasing prospect into the fields of learning.
With Herbart, therefore, a many-sided, harmonious interest promotes _will-energy_ through all the efforts of learning from childhood up, and when the work of general education has been completed, the youth is ready to launch out into the world with a strong, healthy appetite for information in many directions. The best fruitage of such a course will follow in the years that succeed school life. Interest is a very practical thing. It is that which gives force and momentum to ideas. It is not knowledge itself, but, like the invisible principle of life, it converts dead matter into living energy. In our schools thus far we have had too much faith in the mechanics of education. Too much virtue has been imputed to facts, to knowledge, to sharp tools. We have now to learn that _incentive_ is a more important thing in education; that is, a direct, permanent, many-sided interest.
By concentration is meant such a connection between the parts of each study and such a spinning of relations and connecting links between different sciences that unity may spring out of the variety of knowledge. History, for example, is a series and collocation of facts explainable on the basis of cause and effect, a development. On the other hand, history is intimately related to geography, language, natural science, literature, and mathematics. It would be impossible to draw real history out by the roots without drawing all other studies out bodily with it. Is there then any reason why school history should ignore its blood relationships to other branches of knowledge?