I never react to events in the outside world; I always react to the sensations in my own body. (...) Even when we think we react to what another person has done, to President Trump's latest tweet, or to a distant childhood memory, the truth is we always react to our immediate bodily sensations. If we are outraged that somebody insulted our nation or our god, what makes the insult unbearable is the burning sensations in the pit of our stomach and the band of pain that grips our heart. Our nation feels nothing, but our body really hurts.

The idea that humans will always have a unique ability beyond the reach of non-conscious algorithms is just wishful thinking.

When you look at the growth of the human economy and its expected growth in the twenty-first century, I expect health will be the most important market of all. Especially as we move from a concept of health which focuses on healing the sick to a concept of upgrading the healthy.

In order to survive in a very small tribe, you needed to know how to do lots of things for yourself: how to make your tools, how to get food, and how to make your clothes - things most of us today don't need to know. The only thing I need to survive is to know history.

I was taught that if you're going to study something, you must understand it deeply and be familiar with primary sources. But if you write a history of the whole world, you can't do this. That's the trade-off.