We should educate more women and girls. Because that is the surest route to controllably, manageably reducing the human population. Educated women have fewer kids. And the kids they do have are better cared for and are more successful. As I like to say, it's not one thing that we need to focus on. It's everything all at once.

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

If you meet somebody who says he or she has never dreamed of flying, I don't believe you. I mean, they're lying.

But as the cerebellum degrades with age, so does the quality of memories. The memories are there, but they're not as good.

But investment in space stimulates society, it stimulates it economically, it stimulates it intellectually, and it gives us all passion.

As you may know, I am a mechanical engineer.

Evolution is one of the most powerful and important ideas ever developed in the history of science. Every question it raises leads to new answers, new discoveries, and new smarter questions. The science of evolution is as expansive as nature itself. It is also the most meaningful creation story that humans have ever found.