There is a certain consideration, and a general duty of humanity, that binds us not only to the animals, which have life and feeling, but even to the trees and plants. We owe justice to people, and kindness and benevolence to all other creatures who may be susceptible of it. There is some intercourse between them and us, and some mutual obligation.

To behave rightly, we ourselves should never lay a hand on our servants as long as our anger lasts. Things will seem different to us when we have quieted and cooled down.

Though we may be learned by another's knowledge, we can never be wise but by our own experience.

The easy, gentle, and sloping path . . . is not the path of true virtue. It demands a rough and thorny road.

The man who thinks he knows does not yet know what knowing is

The worst condition of humans is when they lose knowledge and control of themselves.

Obsession is the wellspring of genius and madness.