Global warming, along with the cutting and burning of forests and other critical habitats, is causing the loss of living species at a level comparable to the extinction event that wiped out the dinosaurs 65 million years ago. That event was believed to have been caused by a giant asteroid. This time it is not an asteroid colliding with the Earth and wreaking havoc: it is us.

The choice to 'do nothing' in response to the mounting evidence is actually a choice to continue and even accelerate the reckless environmental destruction that is creating the catastrophe at hand.

It's as if we think the laws of physics are subject to debate and amendment and political contributions can sway the laws of physics.

You know, in physics there's the old law for every action there's a equal amount of reaction. Sometimes that's true in politics. If somebody's out there making nonsensical statements, but wielding power behind them a lot of people say, "Well, I need to react to that." I think that's happening.

There's such a wide variation in tax systems around the world, it's difficult to imagine a harmonized CO2 tax that every country agrees to. That's not in the cards in the near term. But the countries that are doing the best job, like Sweden, are already doing both of these. I think that eventually we'll use both of them but we need to get started right away and the cap-and-trade is a proven and effective tool.

I doubt nuclear power will play a much larger role than it does now.

There's no doubt that in the last two to three decades, American democracy has been hacked. It was based on the regular harvesting of the wisdom of crowds, but now big sources of special interest money are able to prevent the passage of almost any meaningful reform that's aimed at the public interest.