One of the reasons I think people are increasingly nervous about U.S. debt is because they think that we are not actually digging ourselves out of the hole, but instead are digging ourselves into a deeper and deeper hole and will not be able to pay it back because we're not actually creating the new technologies that will enable us to pay back and the money somehow is not really being invested in the future or in progress.

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.

Anti-aging is an extremely under-explored field.

There is perhaps no specific time that is necessarily right to start your company or start your life. But some times and some moments seem more auspicious than others. Now is such a moment. If we don’t take charge and usher in the future - if you don’t take charge of your life - there is the sense that no one else will.

EVERY MOMENT IN business happens only once. The next Bill Gates will not build an operating system. The next Larry Page or Sergey Brin won’t make a search engine. And the next Mark Zuckerberg won’t create a social network. If you are copying these guys, you aren’t learning from them.

Technology is probably the single biggest driver of productivity gains for the developed countries. For example, I think it's much more important than free trade.

Every business is successful exactly to the extent that it does something others cannot.