Hope and optimism aren't just attitudes, they are life strategies.

The great thing about cheap natural gas, again it's cheap, and it provides a cleaner alternative to coal. But it's still a fossil fuel, and because it's still a fossil fuel, it still emits carbon.

The financial crisis just made the hole deeper, which is why our stimulus needs to be both big and smart, both financially and educationally stimulating. It needs to be able to produce not only more shovel-ready jobs and shovel-ready workers, but more Google-ready jobs and Windows-ready and knowledge-ready workers.

Remember, the difference between the world frozen over, in an ice ball, and the warming period we're in now is just 6 degrees centigrade. A change of just 1 degree can have a huge effect.

Communism was a great system for making people equally poor - in fact, there was no better system in the world for that than communism. Capitalism made people unequally rich.

You'll know the green revolution has been won when the word 'green' disappears.

My mom enlisted in the U.S. Navy in World War II, and my parents actually bought our home thanks to the loan she got through the GI Bill.