It is obvious that the performance of a stock last year or last month is no reason, per se, to either own it or to not own it now. It is obvious that an inability to "get even" in a security that has declined is of no importance. It is obvious that the inner warm glow that results from having held a winner last year is of no importance in making a decision as to whether it belongs in an optimum portfolio this year.

I knew a lot about what I did when I was 20. I had read a lot, and I aspired to learn everything I could about the subject.

The investor of today does not profit from yesterday's growth.

Every company that has an economist working for him has one employee too many.

Does the business have favourable long term prospects?

We also believe candour benefits us as managers. The CEO who misleads often in public eventually misleads himself in private.

If you are a professional and have confidence, then I would advocate lots of concentration.