If you know how to value businesses, it's crazy to own 50 stocks or 40 stocks or 30 stocks, probably because there aren't that many wonderful businesses understandable to a single human being in all likelihood. To forego buying more of some super-wonderful business and instead put your money into #30 or #35 on your list of attractiveness just strikes Charlie and me as madness.

Buy into a company because you want to own it, not because you want the stock to go up.

Diversification may preserve wealth, but concentration builds wealth.

Focus on return on equity, not earnings per share.

Larger sums may be an advantage at some cases and a disadvantage at others.

I've often felt there might be more to be gained by studying business failures than business successes.

I make plenty of mistakes and I'll make plenty more mistakes, too. That's part of the game. You've just got to make sure that the right things overcome the wrong ones.