Scientists had said, "If you keep burning coal and gas and oil, you will melt the Arctic." And then the Arctic melted just as they had predicted. Did Shell Oil look at the melt and say, "Huh, maybe we should go into the solar-panel business instead?" No, Shell Oil looked at that and said, "Oh, well, now that it's melted it will be easier to drill for more oil up there." That's enough to make you doubt about the big brain being a good adaptation.

We can no longer imagine that we are part of something larger than ourselves - that is what all this boils down to.

Certainly, packets of sea ice, in say the Arctic, which have failed to fully reform in the last couple of years.

Ice in the West Antarctic and over Greenland, i.e., ice that's over a rock at the moment, that will raise the level of the sea as it slides into the ocean, putting at risk everyone and everything that lives on the coasts, and that includes an enormous percentage of the world's people.

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.

Profiting from companies that are overloading the atmosphere with carbon and changing the atmosphere is wrong.

We're clearly not going to stop global warming at this point. We've already raised the temperature of the planet one degree. We've got another degree in the pipeline from carbon we've already emitted. What we're talking about now is whether we're going to have a difficult, difficult century, or an impossible one.