It's an important point, and every little bit helps not least because those who make those kinds of changes are more likely to make their voices heard as citizens. But the ultimate solutions are going to come through policies.

We have to use our reasoning capacity and set long-term goals based on our deepest values.

When fear displaces reason, the result is often irrational hatred and division.

In order to solve the climate crisis, we need to solve the democracy crisis.

I think George W. Bush has a warm, engaging personality. But, you know, the presidency is more than just a popularity contest.

Where solar energy is concerned - and wind energy and battery storage and electric vehicles and efficiency technologies - that is what we are now seeing. So, yes, I'm very optimistic, but anyone who works on the climate crisis has an internal struggle between hope and despair. I won't deny that, but hope has always prevailed in my outlook.

Unless we stop dumping 70 million tons of global warming pollution into the atmosphere every 24 hours, which we are doing right now ... the continued acceleration of this pollution would destroy the future of human civilization.