Thinking is one thing no one has ever been able to tax.

All human development, no matter what form it takes, must be outside the rules; otherwise we would never have anything new.

Action without intelligence is a form of insanity, but intelligence without action is the greatest form of stupidity in the world.

I've never heard of anyone stumbling on something sitting down.

In many ways ideas are more important than people - they are much more permanent.

The difference between intelligence and an education is this: that intelligence will make a good living for you, but education won't do much for you at all.

It doesn't matter if you try and try and try again, and fail. It does matter if you try and fail, and fail to try again.