Never doubt that a small group of thoughtful, committed citizens can change the world; indeed, it's the only thing that ever has.

He gave the I have a dream speech, not the I have a plan speech.

I now inhabit a life I don’t deserve, but we all walk this earth feeling we are frauds. The trick is to be grateful and hope the caper doesn’t end soon.

The great use of life is to spend it for something that will outlast it.

A wise man can learn more from a foolish question than a fool can learn from a wise answer.

Life is lived in four quarters. Twenty-five years each. 0 to 25 years of age is your first quarter, 25 to 50 years old is your second, 50 to 75 is your third, and 75 to 100 is your fourth. Don't forget. Most people don't make it to the fourth quarter. And your body starts to fall apart in the third quarter. So make the most of your second quarter. Don't waste it.

You will become way less concerned with what other people think of you when you realize how seldom they do.

The mind can be convinced but the heart must be won.

Over the long term, the future is decided by optimists.