I think that intelligence is such a narrow branch of the tree of life - this branch of primates we call humans. No other animal, by our definition, can be considered intelligent. So intelligence can't be all that important for survival, because there are so many animals that don't have what we call intelligence, and they're surviving just fine.

We should not be ashamed of not having answers to all questions yet... I'm perfectly happy staring somebody in the face saying, 'I don't know yet, and we've got top people working on it.' The moment you feel compelled to provide an answer, then you're doing the same thing that the religious community does: providing answers to every possible question.

For all we know, the aliens have already done this and unwittingly concluded that there was no intelligent life on Earth. They would now be looking elsewhere. A more humbling possibility would be if aliens had become aware of the technologically proficient species that now inhabits Earth, yet they had drawn the same conclusion.

When I was a kid, I thought that if everyone looked up the way I did then everyone would want to study the universe just like me - how could they not? This naiveté is what tells me that my interest was more a calling than a rational comparative assessment about what to be when I grew up.

For centuries, epilepsy was the exact expectation of someone being possessed by the Devil. There was no better explanation, and it allows you to admit the existence of the Devil. If there's a Devil, that mean's there's a God.

What I’m saying is, when different experiments give you the same result, it is no longer subject to your opinion. That’s the good thing about science: It’s true whether or not you believe in it. That’s why it works.

My investment of time, as an educator, in my judgment, is best served teaching people how to think about the world around them. Teach them how to pose a question. How to judge whether one thing is true versus another.