The idea of excessive diversification is madness. Wide diversification, which necessarily includes investment in mediocre businesses, only guarantees ordinary results.

In the corporate world, if you have analysts, due diligence, and no horse sense, you've just described hell.

What do you want to avoid? Such an easy answer: sloth and unreliability. If you're unreliable it doesn't matter what your virtues are. You're going to crater immediately. Doing what you have faithfully engaged to do should be an automatic part of your conduct. You want to avoid sloth and unreliability.

Ben Franklin and Samuel Johnson, he credits their wisdom for his success. "They were both utterly brilliant men. And powerful communicators. Both have helped me all the way through life. Their lessons are easy to assimilate."

The big money is not in the buying and selling ... but in the waiting.

The basic concept of value to a private owner and being motivated when you're buying and selling securities by reference to intrinsic value instead of price momentum - I don't think that will ever be outdated.

I like people admitting they were complete stupid horses' asses. I know I'll perform better if I rub my nose in my mistakes. This is a wonderful trick to learn.