Institutio Oratoria
Quintilian
Quintilian. Institutio Oratoria, Volume 1-4. Butler, Harold Edgeworth, translator. Cambridge, Mass; London: Harvard University Press, William Heinemann Ltd., 1920-1922.
And further owing to the general pliability of childhood, they follow their instructors with greater simplicity and without attempting to measure their own progress: for as yet they do not even appreciate the nature of their work. Finally, as I have often noticed, the senses are less affected by mere hard work than they are by hard thinking.
Moreover there will never be more time for such studies, since at this age all progress is made through listening to the teacher. Later when the boy has to write by himself, or to produce and compose something out of his own head, he will neither have the time nor the inclination for the exercises which we have been discussing.
Since, then, the teacher of literature neither can nor ought to occupy the whole day, for fear of giving his pupil a distaste for work, what are the studies to which the spare time should preferably be devoted?
For I do not wish the student to wear
Why did Plato bear away the palm in all these branches of knowledge which in my opinion the future orator should learn? I answer, because he was not merely content with the teaching which Athens was able to provide or even with that of the Pythagoreans whom he visited in Italy, but even approached the priests of Egypt and made himself thoroughly acquainted with all their secret lore.