Very few people on earth ever get to say: 'I am doing, right now, the most important thing I could possibly be doing.' If you'll join this fight that's what you'll get to say

It is a complete embarrassment and literally shameful that the country that first of all invented environmentalism and gave it to the world, and second of all did all the science originally around climate and global warming and presented that to the world, has been the country that has refused to participate in a constructive way to the solution.

We have to figure out ways to scare and entice our leaders more effectively than the fossil fuel industry has managed to scare and entice them. They've got the big checkbooks. We've got to have the big crowd.

The laws of Congress and the laws of physics have grown increasingly divergent, and the laws of physics are not likely to yield.

Climate change is the single biggest thing that humans have ever done on this planet. The one thing that needs to be bigger is our movement to stop it.

To me, it's more important to take the 60-70% of people who really understand that there's a problem [of climate change] and get some percentage of them active than to try and stamp out the last embers of pre-scientific thought.

When you go to China and the developing world, people understand more clearly the dangers that are coming at them because they're living closer to the margin. They don't have any of the false sense of invulnerability that Americans have. People from developing countries also feel that it's their right, if you're talking in terms of justice, to use fossil fuels like we did for a hundred years to get rich. It's hard for them to give up that vision.