Scientists tend to focus on what they don't know more than what they do know. And there are a lot of things we still don't know about the climate. But we know the difference between climate variability and climate change, and right now the amount of carbon in the atmosphere is well outside the variability pattern - and that's quite quantifiable.

If you are self-motivated, wow, this world is tailored for you. The boundaries are all gone. But if you're not self-motivated, this world will be a challenge because the walls, ceilings and floors that protected people are also disappearing. That is what I mean when I say "it is a 401(k) world." Government will do less for you. Companies will do less for you. Unions can do less for you. There will be fewer limits, but also fewer guarantees. Your specific contribution will define your specific benefits much more. Just showing up will not cut it.

If we don't have a more serious energy policy, the difference between a good day and bad day for America from here on will hinge on how the 86-year-old king of Saudi Arabia manages...change.

The reason that we are becoming less equal is because of the greater requirements, secure requirements, for a good job. This goes back to the '80s basically, this started changing as globalization and the IT revolution merged, and each started to drive the other.

We have to fight the terrorists as if there were no rules and preserve our open society as if there were no terrorists.

My mother-in-law says if you want to live like a Republican, vote like a Democrat. That if you are a part of the group that is doing well in this system, you owe it to yourself and to others to look out for them and make sure you are always building a ladder for others to join you.

I think that the drama of people rising up demanding their own freedom is one that resonates very deeply with America. I think that President Barack Obama has tried and would like to find a way to relate to the Arab Spring, but I think he also wants to be, rightly, very careful that we don't take it over. It is very important that they own this. He is trying to influence it this way but without, "We're so never going to go to the extreme of Iraq and putting boots on the ground again."