Whatever my current beliefs are, on any topic, they're all open to being changed by the right facts and the right evidence.

I was much more of a naïve techno-optimist than I am now. I still believe that technology can help us come out of this situation with a richer humanity with less impact on the planet, but now I think it has to be paired with effective policy in order to achieve that.

Just like you could dump oil into the Cuyahoga in the 60s and let someone else foot the bill, today you can pump CO2 into the atmosphere and let the whole world foot the bill.

You have to be able to generate usable energy without greenhouse gas emissions and you have to be able to do it cheaply if you want people to choose that approach.

That, to me, is a kind of brilliant environmental ju-jitsu - using the energy of the market and the profit-motive to get businesses to invest in preserving and improving natural systems.

There are really two kinds of optimism. There's the complacent, Pollyanna optimism that says "don't worry - everything will be just fine" and that allows one to just lay back and do nothing about the problems around you. Then there's what we call dynamic optimism. That's an optimism based on action.

If your incentives are set up wrong - if for some reason you reward people for behavior that's actually bad for your customers or your organization - then you're going to encourage that behavior.