I am as bad as the worst, but, thank God, I am as good as the best.

The limits of the possible can only be defined by going beyond them into the impossible.

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

To go too far is as bad as to fall short.

Believe you can and you're halfway there.

Be happy, but never satisfied.

The only way of discovering the limits of the possible is to venture a little way past them into the impossible.

We are what we repeatedly do. Excellence, then, is not an act, but a habit.

The superior man thinks only of virtue; the common man thinks only of comfort.

We need never be ashamed of our tears.

You are never too old to become younger!

Find out who you are and do it on purpose.

I'd rather be hated for who I am, than loved for who I am not.

You yourself, as much as anybody in the entire universe, deserve your love and affection.

If you want a thing done well, do it yourself.

Everything I've ever done was out of fear of being mediocre.

You have to make the rules, not follow them.

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

Don't wish it were easier, wish you were better.

It always seems impossible until it's done.

The deeds you do may be the only sermon some persons will hear today.