Thomas A. Edison

I have friends in overalls whose friendship I would not swap for the favor of the kings of the world.

Show me a thoroughly satisfied man and I will show you a failure.

Restlessness is discontent and discontent is the first necessity of progress. Show me a thoroughly satisfied man and I will show you a failure.

Many of life's failures are people who did not realize how close they were to success when they gave up.

There will one day spring from the brain of science a machine or force so fearful in its potentialities, so absolutely terrifying, that even man, the fighter, who will dare torture and death in order to inflict torture and death, will be appalled, and so abandon war forever.

Be courageous. I have seen many depressions in business. Always America has emerged from these stronger and more prosperous. Be brave as your fathers before you. Have faith! Go forward!

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

Hell, there are no rules here - we're trying to accomplish something.

The best thinking has been done in solitude. The worst has been done in turmoil.

To my mind the old masters are not art their value is in their scarcity.