Revelation replaced investigation.

Any time scientists disagree, it's because we have insufficient data. Then we can agree on what kind of data to get; we get the data; and the data solves the problem. Either I'm right, or you're right, or we're both wrong. And we move on. That kind of conflict resolution does not exist in politics or religion.

Ever since there have been people, there have been explorers, looking in places where other hadn't been before. Not everyone does it, but we are part of a species where some members of the species do, to the benefit of us all.

There are countless space activities that would be no less exciting than the moon missions were, I have no doubt. The search for life on Mars, for example.

We already know the limits of Einstein's theories. From the centers of black holes at the very beginning of the universe - we call these singularities - Einstein's equations fail. In fact, people have joked that's where God is dividing by zero.

Imagine a life-form whose brainpower is to ours as ours is to a chimpanzee’s. To such a species, our highest mental achievements would be trivial. Their toddlers, instead of learning their ABCs on Sesame Street, would learn multivariable calculus on Boolean Boulevard. Our most complex theorems, our deepest philosophies, the cherished works of our most creative artists, would be projects their schoolkids bring home for Mom and Dad to display on the refrigerator door.

The StarTalks - while kids can watch them, they're actually targeted at adults. Because adults outnumber kids five to one, and adults vote, and adults wield resources, and adults are heads of agencies. So if we're going to affect policy, or affect attitudes, for me, the adults have always been the target population.