All of us can make changes, but the changes that are most needed are not light bulbs and windows but laws and policies and treaties. So, yes, we are in a phase of this (climate protection) struggle where civic and political action is at the top of the list.

Take it from me: Elections matter.

We have to abandon the conceit that isolated personal actions are going to solve this crisis. Our policies have to shift.

Distributed intelligence is the key to the advancement of human civilization. Dictatorships, communist countries, monarchies in the past all eventually collapsed because of their inefficiency in moving information.

There's a law of physics: For every action there's an equal and opposite reaction. And sometimes that shows up in politics and society. And I think that the reaction to President Trump's decision on the Paris Agreement has been much stronger than I had even hoped for. And the determination being expressed by so many people in state governments, city governments, in the business community, the investor community, is really heartening to me.

For a free country to continue thriving, there have to be regular reforms, because any society, any economy that stays in place, you're going to see repeated attempts to exploit the openings for twisting policy to the advantage of those who already have wealth and power.

Speaking from my own religious tradition in this Christmas season, 2,000 years ago a homeless woman gave birth to a homeless child in a manger because the inn was full.