There's real economic costs to climate change - So, Superstorm Sandy led to billions of dollars in damages. The fires out in the west, 70 million dollars a day are being spent in fighting fires that have clearly been exacerbated by drought and climate change. So, people have pointed out the true dollars and cents cost of inaction on climate change.

It's extremely hard to know what the economic consequences of any decision will be. And I'm not a, a, a financial analyst, so I, I generally don't try to make some kind of prediction about that.

It really is a very radical call ... to reject materialism as our central value and to think about the sanctity of life and what that really means if we take it seriously.

When we damage the environment, we damage everything we depend on.

I think Pope Francis is our Pope Francis. I mean, the point of him is that he's a global leader, and he's trying, I think he's embracing that role.

At a recent conference, a colleague told one of us that in IPCC discussions, some scientists have been reluctant to make strong claims about the scientific evidence, lest contrarians "attack us". Another said that she'd rather err on the side of conservatism in her estimates, because then she feels more "secure."

Scientific monitoring is going to be terrifically important, because whatever steps we take ... we will have to monitor those steps in order to know if they're actually working.