Strength of mind rests in sobriety; for this keeps your reason unclouded by passion.

The only way of finding the limits of the possible is by going beyond them into the impossible.

What's the world's greatest lie?... It's this: that at a certain point in our lives, we lose control of what's happening to us, and our lives become controlled by fate.

The fact that the great scientist believed in flying machines was the one thing that encouraged us to begin our studies.

Defeat is not defeat unless accepted as a reality-in your own mind.

No great discovery was ever made without a bold guess.

Yesterday is gone. Tomorrow has not yet come. We have only today. Let us begin.

Learn from yesterday, live for today, hope for tomorrow.

Don't fear failure. Not failure, but low aim, is the crime. In great attempts it is glorious even to fail.

If you want creative workers, give them enough time to play.

My optimism wears heavy boots and is loud.

I wouldn't say I was the best manager in the business. But I was in the top one.

Perseverance is failing 19 times and succeeding the 20th.

Ask for what you want and be prepared to get it!

The starting point of all achievement is desire.

Weakness of attitude becomes weakness of character.

The world is the great gymnasium where we come to make ourselves strong.

It always seems impossible until it's done.

Life is like riding a bicycle. To keep your balance, you must keep moving.

If you think in terms of a year, plant a seed; if in terms of ten years, plant trees; if in terms of 100 years, teach the people.

When everything seems to be going against you, remember that the airplane takes off against the wind, not with it ....