Warren spends 70 hours a week thinking about investing .

It would be one of the most irritating experiences in the world to do a lot of work to uncover a fraud and then at have it go from X to 3X and at h the crooks happily partying with your money while you're meeting margin calls. Why would you want to go within hailing distance of that?

So, economics should emulate physics' basic ethos, but its search for precision in physics-like formulas is almost always wrong in economics.

Investing is where you find a few great companies and then sit on your ass.

People like the robber barons assumed that the doctrine of the survival of the fittest authenticated them as deserving power. You know, "I'm the richest. Therefore, I'm the best. God's in his heaven, etc." And that reaction of the robber barons was so irritating to people that it made it unfashionable to think of an economy as an ecosystem. But the truth is that it is a lot like an ecosystem. And you get many of the same results.

This is an amazingly sound place. We are more disaster-resistant than most other places. We haven't pushed it as hard as other people would have pushed it. I don't want to go back to Go. I've been to Go. A lot of our shareholders have a majority of their net worth in Berkshire, and they don't want to go back to Go either.

Assume life will be really tough, and then ask if you can handle it. If the answer is yes, you've won.