I like to buy things I can understand. I do a lot of research on things.

Investing in a market where people believe in efficiency is like playing bridge with someone who has been told it doesn't do any good to look at the cards.

I have pledged - to you, the rating agencies and myself - to always run Berkshire with more than ample cash. We never want to count on the kindness of strangers in order to meet tomorrow's obligations. When forced to choose, I will not trade even a night's sleep for the chance of extra profits.

Everybody's got a different circle of competence. The important thing is not how big the circle is. The important thing is staying inside the circle.

The banking business is no favorite of ours. When assets are twenty times equity - a common ratio in this industry - mistakes that involve only a small portion of assets can destroy a major portion of equity. And mistakes have been the rule rather than the exception at many major banks.

The fact that people will be full of greed, fear, or folly is predictable. The sequence is not predictable.

I want to be able to explain my mistakes. This means I do only the things I completely understand.