Do I think that people should in the best of all possible worlds have to go to jail for wanting the US government to pay attention to the warnings of scientists about climate change? Not really. I mean, in a rational world, if all the scientists said, "The worst thing that ever happened is about to happen and here's what you should do to stop it," you would expect any rational system to say, "Oh, sure, OK, let's do something about it." But that's not the world we live in. In the world we live in, you do need people willing to stand up, fight, march and sometimes go to jail.

[Kids] will grow up into a world that's difficult and wonderful, and they'll make the best of it they can, and hopefully help turn it in the best possible direction.

I try not to be either optimistic or pessimistic. I try not to think about outcomes on that scale. My job, it seems to me, is to wake up every morning and figure out how to cause as much trouble for the fossil fuel industry as I can.

There is a tendency at every important but difficult crossroad to pretend that it's not really there.

We finally know where the red line for climate really is. After the rapid melt of arctic ice in the summer of 2007, our best scientists, led by NASA's Jim Hansen, went back to work and produced a series of papers showing that with more than 350 ppm (parts per million) of carbon dioxide in the atmosphere, we couldn't have a planet "similar to the one on which civilization developed and to which life on earth is adapted."

The ability to write compelling emails may be the single most useful talent an organizer can possess.

A voluntary simplification of life-styles is not beyond our abilities, but it is probably outside our desires.