You might say, well, aren't people saying that about wind and solar today? Not really. Only in the super-narrow sense that the capital costs per output, when the wind is blowing, is slightly lower.

If you get health, then you have opportunity for literacy. Health first, then literacy. Once you have literacy, then you have a chance to bring in the new tools of communication. Let people reach out and have access to the latest advances.

The difference between a stranger sending you a message that you might be interested in at a very low volume level, no repetition, just sending it to very few people, and that being done as spam - those things get close enough that you want to be careful never to filter out something that's legitimate.

Robotics and other combinations will make the world pretty fantastic compared with today.

[Africa] is the one continent where you still have a lot more young people than old people. So making sure they're healthy, good nutrition, good education. That'll be important for the world.

Take agriculture, where we haven't done much, or sanitation; saying, "okay, we will be able to make a really huge effort there." It really energized the foundation and half of what we've gotten done in this last decade is because Warren [Buffett] trusted us.

There are no significant bugs in our released software that any significant number of users want fixed.