If you decide to become a dancer on Broadway, never say who your favorite dance partner is, because members of the media will presume you never want to dance with anybody else.

I say to the grown-ups, 'If you want to deny evolution and live in your world that's completely inconsistent with everything we've observed in the universe that's fine. But don't make your kids do it.'

The most serious problem facing humankind is climate change. All of these people breathing and burning our atmosphere has led to an extraordinarily dangerous situation. I hope next generation will emerge and produce technology, regulations, and a worldview that enable as many of us as possible to live happy healthy lives.

Hard to find anything lovelier than a tree. They grow at right angles to a tangent of the nominal sphere of the Earth.

Climate change is happening, humans are causing it, and I think this is perhaps the most serious environmental issue facing us.

As my old professor Carl Sagan said so often, 'When you’re in love, you want to tell the world.’ And I base my beliefs on the information and the process that we call science. It fills me with joy to make discoveries every day of things I’ve never seen before. It fills me with joy to know that we can pursue these answers. It is an astonishing thing that we are — you and I are one of the ways the universe knows itself.

The philosophy of science is inherent in the process. This is to say, you think critically, you draw a conclusion based on evidence, but we all pursue discovery based on our observations. That's where science starts.