We believe that almost all really good investment records will involve relatively little diversification. The basic idea that it was hard to find good investments and that you wanted to be in good investments, and therefore, you'd just find a few of them that you knew a lot about and concentrate on those seemed to me such an obviously good idea. And indeed, it's proven to be an obviously good idea. Yet 98% of the investing world doesn't follow it. That's been good for us.

It's natural that you'd have more brains going into money management. There are so many huge incomes in money management and investment banking - it's like ants to sugar. There are huge incentives for a man to take up money management as opposed to, say, physics, and it's a lot easier.

The idea of caring is that someone is making money faster [than you are] is one of the deadly sins. Envy is a really stupid sin because it’s the only one you could never possibly have any fun at. There’s a lot of pain and no fun. Why would you want to get on that trolley?

To some extent, stocks are like Rembrandts. They sell based on what they've sold in the past. Bonds are much more rational. No-one thinks a bond's value will soar to the moon.

If you, like me, lived through 1973-74 or even the early 1990s... There was a waiting list to get OUT of the country club - that's when you know things are tough. If you live long enough, you'll see it.

It's not given to human beings to have such talent that they can just know everything about everything all the time. But it is given to human beings who work hard at it - who look and sift the world for a mispriced bet - that they can occasionally find one. And the wise ones bet heavily when the world offers them that opportunity. They bet big when they have the odds. And the rest of the time they don't. It's just that simple.

Berkshire's whole record has been achieved without paying one ounce of attention to the efficient market theory in its hard form. And not one ounce of attention to the descendants of that idea, which came out of academic economics and went into corporate finance and morphed into such obscenities as the capital asset pricing model, which we also paid no attention to. I think you'd have to believe in the tooth fairy to believe that you could easily outperform the market by seven-percentage points per annum just by investing in high volatility stocks.