“I’m learning men cannot teach men to build their castles with bricks. time must do that.”

“The Duke would not pay for the works. He says that the Castle can never be taken. That is called hubris, Giacomo, the belief that you are never wrong. Believing you are never wrong is an error that afflicts great men. I have learned that to be right you must first be wrong many times. Without making errors--and learning from them--a man cannot find the truth.”

“If women are expected to do the same work as men, we must teach them the same things.”

“That men do not learn very much from the lessons of history is the most important of all the lessons that history has to teach.”

“Whatever he learned from me, I learned well from Leonardo that teaching is a matter of drawing out from men what is already in their hearts, and that men learn only what they want to.”

“Teach to the young, men's enduring truths, and let the learned amuse themselves with their passing errors.”