Finding a single investment that will return 20% per year for 40 years tends to happen only in dreamland. In the real world, you uncover an opportunity, and then you compare other opportunities with that. And you only invest in the most attractive opportunities. That's your opportunity cost. That's what you learn in freshman economics. The game hasn't changed at all. That's why Modern Portfolio Theory is so asinine.

People have always had this craving to have someone tell them the future. Long ago, kings would hire people to read sheep guts. There's always been a market for people who pretend to know the future. Listening to today's forecasters is just as crazy as when the king hired the guy to look at the sheep guts.

The laws of thermodynamic s are such that if the water is getting warmer - and I believe it is - the energy of the weather is going to go up.

What's fascinating . . .is that you could now have a business that might have been selling for $10 billion where the business itself could probably not have borrowed even $100 million. But the owners of that business, because its public, could borrow many billions of dollars on their little pieces of paper- because they had these market valuations. But as a private business, the company itself couldn't borrow even 1/20th of what the individuals could borrow.

We believe there should be a huge area between everything you should do and everything you can do without getting into legal trouble. I don't think you should come anywhere near that line. We don't deserve much credit for this. It helps us make more money. I'd like to believe that we'd behave well even if it didn't work. But more often, we've made extra money from doing the right thing. Ben Franklin said I'm not moral because of it's the right thing to do - but because it's the best policy.

We don't have an isolated group [of senior managers] surrounded by servants. Berkshire's headquarters is a tiny little suite. We just came back from Berkshire's board meeting; it had moved up to the board room of the Kiewit company and [it was so large and luxurious that] I felt uncomfortable.

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.