By three methods we may learn wisdom: First, by reflection, which is noblest; Second, by imitation, which is easiest; and third by experience, which is the bitterest.

Does wisdom perhaps appear on the earth as a raven which is inspired by the smell of carrion?

He who devotes sixteen hours a day to hard study may become at sixty as wise as he thought himself at twenty.

It is astonishing with how little wisdom mankind can be governed, when that little wisdom is its own.