One needs only to get old to become milder; I don't see anyone make a mistake I hadn't also made.

I know nothing more mocking than a devil that despairs.

Yet he who grasps the moment's gift, He is the proper man.

Mastery is often taken for egotism.

Science has been seriously retarded by the study of what is not worth knowing and of what is not knowable.

Ye great teachers: listen to what you say!

One lives but once in the world.