I stand by my assertions that although you can know what happens to any individual species that you modify, you cannot be certain what will happen to the ecosystem. Also, we have a strange situation where we have malnourished fat people. It's not that we need more food. It's that we need to manage our food system better.

The more you find out about the world, the more opportunities there are to laugh at it.

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

Science provides a much more satisfactory way to seek answers than does any religion.

When we see the shadow on our images, are we seeing the time 11 minutes ago on Mars? Or are we seeing the time on Mars as observed from Earth now? It's like time travel problems in science fiction. When is now; when was then?

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.

There really is no such thing as race. We all came from Africa. We are all of the same stardust. We are all going to live and die on the same planet, a Pale Blue Dot in the vastness of space. We have to work together.