Most people early achieve and later intensify a tendency to process new and disconfirming information so that any original conclusion remains intact. They become people of whom Philip Wylie observed: "You couldn't 't squeeze a dime between what they already know and what they will never learn."

In the 1930s, there was a stretch where you could borrow more against the real estate than you could sell it for. I think that's what's going on in today's private-equity world.

When you locate a bargain, you must ask, 'Why me, God? Why am I the only one who could find this bargain?'

You must know the big ideas in the big disciplines, and use them routinely - all of them, not just a few. Most people are trained in one model - economics, for example - and try to solve all problems in one way. You know the old saying: to the man with a hammer, the world looks like a nail. This is a dumb way of handling problems.

We regard using [a stock's] volatility as a measure of risk is nuts. Risk to us is 1) the risk of permanent loss of capital, or 2) the risk of inadequate return. Some great businesses have very volatile returns - for example, See's [a candy company owned by Berkshire] usually loses money in two quarters of each year - and some terrible businesses can have steady results.

I have concluded that most PhD economists under appraise the power of the common-stock-based "wealth effect," under current extreme conditions... "Wealth effects" involve mathematical puzzles that are not nearly so well worked out as physics theories and never can be... What has happened in Japan over roughly the last ten years has shaken up academic economics, as it obviously should, creating strong worries about recession from "wealth effects" in reverse.

Without numerical fluency, in the part of life most of us inhibit, you are like a one-legged man in an ass-kicking contest.