L'art d'enseigner n'est que l'art d'éveiller la curiosité des jeunes âmes pour la satisfaire ensuite.
The whole art of teaching is only the art of awakening the natural curiosity of young minds for the purpose of satisfying it afterwards.

Coolidge is a better example of evolution than either Bryan or Darrow, for he knows when not to talk, which is the biggest asset the monkey possesses over the human.
[Referring to the Scopes trial, with Darrow defending a teacher being prosecuted for teaching evolution in the state of Tennessee.]

God help the teacher, if a man of sensibility and genius, when a booby father presents him with his booby son, and insists on lighting up the rays of science in a fellow's head whose skull is impervious and inaccessible by any other way than a positive fracture with a cudgel.

Lecturing after a fashion is easy enough ; teaching is a very different affair. ... The transmission of ideas from one mind to another, in a simple unequivocal form, is not always easy ; but in teaching, the object is not merely to convey the idea, but to give a lively and lasting impression; something that should not merely cause the retention of the image, but in such connection as to excite another process, ' thought.'

Nothing could have been worse for the development of my mind than Dr. Butler's school, as it was strictly classical, nothing else being taught, except a little ancient geography and history. The school as a means of education to me was simply a blank. During my whole life I have been singularly incapable of mastering any language. Especial attention was paid to versemaking, and this I could never do well. I had many friends, and got together a good collection of old verses, which by patching together, sometimes aided by other boys, I could work into any subject.

Only dead mathematics can be taught where the attitude of competition prevails: living mathematics must always be a communal possession.

Teaching is not a lost art, but the regard for it is a lost tradition.

There is in the chemist a form of thought by which all ideas become visible in the mind as strains of an imagined piece of music. This form of thought is developed in Faraday in the highest degree, whence it arises that to one who is not acquainted with this method of thinking, his scientific works seem barren and dry, and merely a series of researches strung together, while his oral discourse when he teaches or explains is intellectual, elegant, and of wonderful clearness.

To teach is to learn twice.