Success is going from failure to failure without a loss of enthusiasm.

If you are going through hell, keep going.

Reality is merely an illusion, albeit a very persistent one.

You should be the change that you want to see in the world.

We are what we repeatedly do. Excellence, then, is a habit.

To believe in something, and not live it, is dishonest.

Change before you have to.

Peace cannot be kept by force. It can only be achieved by understanding.

Opportunities multiply as they are seized.

The United States invariably does the right thing, after having exhausted every other alternative.

We must respect other religions, even as we respect our own. Mere tolerance thereof is not enough.

Knowledge will give you power, but character, respect.

Physical concepts are free creations of the human mind, and are not, however it may seem, uniquely determined by the external world. In our endeavor to understand reality we are somewhat like a man trying to understand the mechanism of a closed watch. He sees the face and the moving hands, even hears its ticking, but he has no way of opening the case. If he is ingenious he may form some picture of a mechanism which could be responsible for all the things he observes, but he may never be quite sure his picture is the only one which could explain his observations. He will never be able to compare his picture with the real mechanism and he cannot even imagine the possibility or the meaning of such a comparison.

No problem can be solved from the same consciousness that created it.

It does not matter how slowly you go so long as you do not stop.

I think it would be a good idea! In reply to a reporter's question "What do you think of Western Civilization?"

In the middle of difficulty lies opportunity.

I love deadlines. I like the whooshing sound they make as they go by.

In the beginning the Universe was created. This has made a lot of people very angry and has been widely regarded as a bad move.

The sayings of Muhammad are a treasure of wisdom not only for Muslims but for all of mankind.