The wind and the sun are free.

I had a detailed plan for my life, but it turned out life had a completely different plan for me. And I feel joy that I have work that feels like it justifies pouring everything I have into it. I never have fallen prey to the illusion that there's any job with as much ability to influence the future as that of President of the United States, but I do feel grateful that I found other ways to do work that serves the public interest.

The symbolism - and the substantive significance - of planting a tree has universal power in every culture and every society on Earth, and it is a way for individual men, women and children to participate in creating solutions for the environmental crisis.

The truth is that we're at a critical juncture in the history of our species and if we don't act soon, we could inhabit a world we don't recognize anymore. But the most important truth is that we are capable of stopping climate change before the worst of its consequences are locked in. The solutions exist - all we need is the will to do something about it.

Today we're dumping 70 million tons of global-warming pollution into the environment, and tomorrow we will dump more, and there is no effective worldwide response. Until we start sharply reducing global-warming pollution, I will feel that I have failed.

...it is appropriate to have an over representation of factual presentations on how dangerous it is, as a predicate for opening up the audience to listen to what the solutions are, and how hopeful it is that we are going to solve this crisis.

In a time of darkness, you don't curse the darkness, you light a candle.