Well-established theories collapse under the weight of new facts and observations which cannot be explained, and then accumulate to the point where the once useful theory is clearly obsolete.

The crisis is a concrete threatening reality today. It stands to get catastrophically worse unless we take action before the accumulation [of] this global warming pollution reaches such toxic levels that the problem becomes bigger than we can solve.

I was born a poor black child.

I didn't realize I was in a Buddhist temple.

We sometimes emphasize the danger in a crisis without focusing on the opportunities that are there. We should feel a great sense of urgency because it is the most dangerous crisis we have ever faced, by far. But it also provides us with opportunities to do a lot of things we ought to be doing for other reasons anyway. And to solve this crisis we can develop a shared sense of moral purpose.

What's really important is how our country gets through Trump period, because nothing's getting done in Washington. Every day it's another set of tweets and another set of controversies. And they're not getting anything done.

The United States is the only nation that can lead the world toward a solution on climate change.