After PayPal, I never thought I would get interested in payments again. But bitcoin is fulfilling PayPal's original vision to create 'the new world currency.'

If you allowed PayPal to pursue its destiny, there are moves it could make to become the largest financial company in the world.

Money is being made programmable. That's a fundamental change with implications we can still barely see.

There is some risk that if the wrong regulatory regime gets adopted in the U.S., then the center of innovation could move to other countries. If blockchains are the next Internet, that would be a very unfortunate development for the U.S.

The thrill of acting is the discovery part, so it all changes, but it has to change in a way that fits what is written. You can't just wander off and get interested in your own tangent.

I'm really convinced that our descendants a century or two from now will look back at us with the same pity that we have toward the people in the field of science two centuries ago.

We couldn't be happier that the show has encouraged kids to have an interest in science and math, but we don't try to do that. We just have fun, which is its own bold statement.

The science of morality is about maximizing psychological and social health. It's really no more inflammatory than that.