Show me a completely contented person and I'll show you a failure.

There is great value in disaster. All our mistakes are burned up. Thank God we can start a new.

It is apparent to me that the possibilities of the aeroplane, which two or three years ago were thought to hold the solution to the [flying machine] problem, have been exhausted, and that we must turn elsewhere.

I do not believe in the God of the theologians; but that there is a Supreme Intelligence I do not doubt.

Just because something doesn't do what you planned it to do doesn't mean it's useless.

What is a college? An institute of learning. What is a business? An institute of learning. Life, itself, is an institute of learning.

I've realized that most of my best ideas have followed a good night's sleep.