The greatest piece of good fortune is that which corrects our deficiencies and redeems our mistakes.
Reading ought to mean understanding; writing ought to mean knowing something; believing ought to mean comprehending; when you desire a thing, you will have to take it; when you demand it, you will not get it; and when you are experienced, you ought to be useful to others.
The stream is friendly to the miller whom it serves; it likes to pour over the mill wheels; what is the good of it stealing through the valley in apathy?
Whoso is content with pure experience and acts upon it has enough of truth. The growing child is wise in this sense.
Theory is in itself of no use, except in so far as it makes us believe in the connection of phenomena.