Obviously, consideration of costs is key, including opportunity costs. Of course capital isn't free. It's easy to figure out your cost of borrowing, but theorists went bonkers on the cost of equity capital. They say that if you're generating a 100% return on capital, then you shouldn't invest in something that generates an 80% return on capital. It's crazy.

You'll find many markets where bottlers of Pepsi and Coke both make a lot of money and many others where they destroy most of the profitability of the two franchises. That must get down to the peculiarities of individual adjustment to market capitalism. I think you 'd have to know the people involved to fully understand what was happening.

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

If you buy something because it's undervalued, then you have to think about selling it when it approaches your calculation of its intrinsic value. That's hard. But if you buy a few great companies, then you can sit on your ass. That's a good thing.

So, economics should emulate physics' basic ethos, but its search for precision in physics-like formulas is almost always wrong in economics.

Every business tries to turn this year's success into next year's greater success. It's hard for me to see why Microsoft is sinful to do this. If it's a sin, then I hope all of Berkshire Hathaway's subsidiaries are sinners. Someone whose salary is paid by U.S.taxpayers is happy to dramatically weaken the one place where we're winning big?!

...in terms of business mistakes that I've seen over a long lifetime, I would say that trying to minimize taxes too much is one of the great standard causes of really dumb mistakes. I see terrible mistakes from people being overly motivated by tax considerations. Warren and I personally don't drill oil wells. We pay our taxes. And we've done pretty well, so far. Anytime somebody offers you a tax shelter from here on in life, my advice would be don't buy it.