There's a saying in the scientific community, that every great truth goes through three phases. First, people deny it. Second, they say that it conflicts with the Bible. Third, they say that they've known it all along.

If you get asteroids about a kilometer in size, those are large enough and carry enough energy into our system to disrupt transportation, communication, the food chains, and that can be a really bad day on Earth.

I have thoughts every day that are themselves tweets.

I'm optimistic. I see no longer people accepting fuzzy thinking in the world. The change is not that people aren't still saying under-informed things. The change is that if you're in power and you say something under-informed, there are people out there with a voice who will take you to task for having done so

In the animal kingdom, one of the keys to survival is to outwit your enemies. And when you're surrounded by carnivores, one of the best strategies is to fade into the background and disappear.

No doubt, the most challenging class of questions in science is the origin of things.

I've always been interested in pop culture. Some of my colleagues think of pop culture as beneath them, or there's the ivory tower and then there's everybody else, and I never could buy into that wall that's been put up by so many people over the decades and even the centuries.