Be sure to set your goals so high that you can't possibly accomplish them in one lifetime. That way you'll always have something ahead of you. I made the mistake of setting my goals too low, and now I'm having a hard time coming up with new ones.

I'd like to say that right now, in the last few years, the Democrats have been closer - have been more pro-environment. The coal industry is pretty well entrenched in the Republican Party and that's one of the things that we need to phase out.

Struggling hard to achieve something is the most fun I get.

Rupert Murdoch is the most dangerous man in the world.

I'm a very good thinker, but I sometimes grab the wrong word. I say something I didn't think through adequately. I mean, I don't type my speeches, then sit up there and read them off the teleprompter, you know. I wing it.

I'm no genius. I'm not at all; I just happen to look five or 10 years ahead and think things through.

If I had to predict, the way things are going, I'd say the chances are about 50-50 that humanity will be extinct or nearly extinct within 50 years. Weapons of mass destruction, disease, I mean this global warming is scaring the living daylights out of me.