History is but the record of the public and official acts of human beings. It is our object, therefore, to humanize our history and deal with people past and present; people who ate and possibly drank; people who were born, flourished and died; not grave tragedians, posing perpetually for their photographs.

Millennial voters are very concerned about climate change and will vote for candidates who are planning to address it. But the systems that are in place - people talk about gerrymandering and the money that's in politics, this is a real thing, a real effect - and it's hard for climate change-denying legislators to get voted out. But I predict it will happen.

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.

I meet so many people who are intimidated by arithmetic.

Intuitively you want some place [such as your phone] to store phone numbers, so you have that part of your brain to do other tasks.

For me, the meaning of life is pretty clear: Living things strive to pass their genes into the future.

Science is the key to our future, and if you don't believe in science, then you're holding everybody back.