People who say it cannot be done should not interrupt those who are doing it.

No great discovery was ever made without a bold guess.

To give pleasure to a single heart by a single act is better than a thousand heads bowing in prayer.

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

Isn't it astonishing that all these secrets have been preserved for so many years just so we could discover them!

This is one small step for a man, one giant leap for mankind.

I don't think necessity is the mother of invention. Invention ... arises directly from idleness, possibly also from laziness. To save oneself trouble.

The secret of genius is to carry the spirit of the child into old age, which means never losing your enthusiasm.

Out of suffering have emerged the strongest souls; the most massive characters are seared with scars.

You can't live a perfect day until you do something for someone who will never be able to repay you.

You have to dream before your dreams can come true.

Whether you think you can, or you think you can't - you're right.

The greatest sin is to think yourself weak

Man needs his difficulties because they are necessary to enjoy success.

When all is said and done, more is said than done.

Do not worry about holding high position; worry rather about playing your proper role.

The way I see it, if you want the rainbow, you gotta put up with the rain.

As long as I'm in great shape, nobody beats me, for sure.

Do you want to know who you are? Don't ask. Act! Action will delineate and define you.

Humans have come into being for the sake of each other, so either teach them, or learn to bear them.

It marks a big step in your development when you come to realize that other people can help you do a better job than you could do alone.