[In picking stocks] You really have to know a lot about business. You have to know a lot about competitive advantage. You have to know a lot about the maintainability of competitive advantage. You have to have a mind that quantifies things in terms of value. And you have to be able to compare those values with other values available in the stock market.

You have to realize the truth of biologist Julian Huxley's idea that 'Life is just one damn relatedness after another' "So you must have the models, and you must see the relatedness and the effects from the relatedness.

You need a different checklist and different mental models for different companies. I can never make it easy by saying, 'Here are three things.' You have to derive it yourself to ingrain it in your head for the rest of your life.

Failure to handle psychological denial is a common way for people to go broke: you have made an enormous commitment to something. You have poured effort and money in. And the more you put in, the more that the whole consistency principle makes you think, "Now it has to work. If I put in just a little more, then it will work."

I never allow myself to have an opinion on anything that I don't know the other side's argument better than they do.

The investment game always involves considering both quality and price, and the trick is to get more quality than you pay for in price. It's just that simple.

Organized common (or uncommon) sense -- very basic knowledge -- is an enormously powerful tool. There are huge dangers with computers. People calculate too much and think too little.