The number one idea is to view a stock as an ownership of the business and to judge the staying quality of the business in terms of its competitive advantage. Look for more value in terms of discounted future cash-flow than you are paying for. Move only when you have an advantage.

This is a good life lesson: getting the right people into your system is the most important thing you can do.

Cicero's words also increased my personal satisfaction by supporting my long-standing rejection of a conventional point of view.

Forgetting your mistakes is a terrible error if you are trying to improve your cognition.

Why should it be easy to do something that, if done well, two or three times, will make your family rich for life?

You have to realize the truth of biologist Julian Huxley's idea that 'Life is just one damn relatedness after another' "So you must have the models, and you must see the relatedness and the effects from the relatedness.

Black-Scholes is a know-nothing system. If you know nothing about value - only price - then Black-Scholes is a pretty good guess at what a 90-day option might be worth. But the minute you get into longer periods of time, it's crazy to get into Black-Scholes. For example, at Costco we issued stock options with strike prices of $30 and $60, and Black-Scholes valued the $60 ones higher. This is insane.