I think there's an awful lot of twaddle and bullshit on EVA. The whole game is to turn retained earnings into more earnings. EVA has ideas about cost of capital that make no sense. Of course, if a company generates high returns on capital and can maintain this over time, it will do well. But the mental system as a whole does not work.

You could argue that [the decline of public schools] is one of the major disasters in our lifetimes. We took one of the greatest successes in the history of the earth and turned it into one of the greatest disasters in the history of the earth.

To the man with only a hammer, every problem looks like a nail.

Black-Scholes is a know-nothing system. If you know nothing about value - only price - then Black-Scholes is a pretty good guess at what a 90-day option might be worth. But the minute you get into longer periods of time, it's crazy to get into Black-Scholes. For example, at Costco we issued stock options with strike prices of $30 and $60, and Black-Scholes valued the $60 ones higher. This is insane.

Personally, I’ve gotten so that I now use a kind of two-track analysis. First, what are the factors that really govern the interests involved, rationally considered? And second, what are the subconscious influences where the brain at a subconscious level is automatically conclusions in various ways — which, by and large, are useful — but which often malfunction? One approach is rationality… And the other is to evaluate the psychological factors that cause subconscious conclusions — many of which are wrong.

We tend to buy things - a lot of things - where we don't know exactly what will happen, but the outcome will be decent.

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.