“Knowing yourself is the beginning of all wisdom.”

“It is the mark of an educated mind to be able to entertain a thought without accepting it.”

“Educating the mind without educating the heart is no education at all.”

“Philosophy can make people sick.”

“For the things we have to learn before we can do them, we learn by doing them.”

“Freedom is obedience to self-formulated rules.”

“With the truth, all given facts harmonize; but with what is false, the truth soon hits a wrong note.”

“The pleasures arising from thinking and learning will make us think and learn all the more. 1153a 23”

“A man without regrets cannot be cured.”