consciousness not only what he has learned, but more as well; since he will recall with ease all that he has learned from teachers or from books, and, at the same time, will be able to pass sound judgment on the objective facts to which his information refers.
4. This will be possible:
(i) If only those subjects that are of real use be taken in hand.
(ii) If these be taught without digression or interruption.
(iii) If a thorough grounding precede instruction in detail.
(iv) If this grounding be carefully given.
(v) If all that follows be based on this grounding, and on nothing else.
(vi) If, in every subject that consists of several parts, these parts be linked together as much as possible.
(vii) If all that comes later be based on what has gone before.
(viii) If great stress be laid on the points of resemblance between cognate subjects.
(ix) If all studies be arranged with reference to the intelligence and memory of the pupils, and the nature of language.
(x) If knowledge be fixed in the memory by constant practice.
We will now consider each of these principles in detail.
First Principle
5. Nature produces nothing that is useless.
For example, nature, when commencing to form a bird, does not give it scales, gills, horns, four feet, or any other organs that it cannot use, but supplies a head, a heart, wings, etc. In the same way a tree is not given ears, eyes, down, or hair, but bark, bast, wood, and roots.
6. Imitation in the arts.—In the same way no one who wishes to grow fruit in his fields, orchards, and gardens,
