All my adult life I've felt drawn to ask long-married couples how they were able to stay together. All of them said the same thing: "We worked hard at it.

No matter how bad things are, you can always make things worse.

Remember brick walls let us show our dedication. They are there to separate us from the people who don't really want to achieve their childhood dreams.

If I work hard enough, there will be things I can do tomorrow that I can't do today.

Too many people go through life complaining about their problems. I've always believed that if you took one tenth the enrgy you put into complaining and applied it to solving the problem, you'd be surprised by how well things can work out.

No matter how bad things are, you can always make things worse. At the same time, it is often within your power to make them better

I understand the arguments about how the billions of dollars spent to put men on the moon could have been used to fight poverty and hunger on Earth. But, look, I'm a scientist who sees inspiration as the ultimate tool for doing good. When you use money to fight poverty, it can be of great value, but too often, you're working at the margins. When you're putting people on the moon, you're inspiring all of us to achieve the maximum of human potential, which is how our greatest problems will eventually be solved. Give yourself permission to dream.