I think China thinks information technology is less important than we think it is in the US, economically, and more important politically. And so Chinese internet companies are extremely political, they're protected behind the great firewall of China, and investment in Alibaba is good as long as Jack Ma stays in the good graces of the Chinese communist party. Alibaba is largely copying various business models from the US; they have combined some things in interesting new ways, but I think it's fundamentally a business that works because of the political protection you get in China.

For a new payment product, you always have to ask, how much better is it than the current solution? So when we started Paypal, for eBay micro merchants, it was much better than getting the 7 to 10 days process of cashing a check in the mail. When you look at stores or physical worlds, places, a lot of these places are already set up to take cash or credit card. Apple Pay may be an incremental improvement, maybe a little bit better. But when you have something that's pretty good and you go to something that's perfect, sometimes it's very hard to drive adoption because the delta is not that big.

I think that markets classically fail in cases where there are public goods that provide benefits that people cannot capture. The big debate is how big these public goods are, where they exist, things of that sort.

The developing world can just do things that are extensive or horizontal, that basically copy. The developed world needs to do things that are intensive or vertical, where we take our civilization to the next level.

Under perfect competition, in the long run no company makes an economic profit.

Higher education holds itself out as a kind of universal church, outside of which there is no salvation.

I think anything that requires real global breakthroughs requires a degree of intensity and sustained effort that cannot be done part time, so it's something you have to do around the clock, and that doesn't compute with our existing educational system.