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.

People calculate too much and think too little.

If you don't allow for self-serving bias in the conduct of others, you are, again, a fool.

A lot of share-buying, not bargain-seeking, is designed to prop stock prices up. Thirty to 40 years ago, it was very profitable to look at companies that were aggressively buying their own shares. They were motivated simply to buy below what it was worth.

In fact I've probably never seen such a wide moat.

Of course the self-serving bias is something you want to get out of yourself. Thinking that what's good for you is good for the wider civilization and rationalizing all these ridiculous conclusions based on this subconscious tendency to serve one's self is a terribly inaccurate way to think.

Our approach has worked for us. Look at the fun we, our managers, and our shareholders are having. More people should copy us. It's not difficult, but it looks difficult because it's unconventional - it isn't the way things are normally done. We have low overhead, don't have quarterly goals and budgets or a standard personnel system, and our investing is much more concentrated than average. It's simple and common sense.