The idea of excessive diversification is madness. Wide diversification, which necessarily includes investment in mediocre businesses, only guarantees ordinary results.

Avoid working directly under somebody you don't admire and don't want to be like.

The way to win is to work, work, work, work and hope to have a few insights And you're probably not going to be smart enough to find thousands in a lifetime. And when you get a few, you really load up. It's just that simple.

We don't have an isolated group [of senior managers] surrounded by servants. Berkshire's headquarters is a tiny little suite. We just came back from Berkshire's board meeting; it had moved up to the board room of the Kiewit company and [it was so large and luxurious that] I felt uncomfortable.

In Gillette's case, they keep surfing along new technology which is fairly simple by the standards of microchips. But it's hard for competitors to do. So they've been able to stay constantly near the edge of improvements in shaving.

How should the best parts of psychology and economics interrelate in an enlightened economist's mind?... I think that these behavioral economics...or economists are probably the ones that are bending them in the correct direction. I don't think it's going to be that hard to bend economics a little to accommodate what's right in psychology.

I'm proud to be associated with the value system at Berkshire Hathaway; I think you'll make more money in the end with good ethics than bad.