Draw a circle around the businesses you understand and then eliminate those that fail to qualify on the basis of value, good management and limited e… - Warren Buffett

My old boss, Ben Graham, told me very early on you get more trouble with a good idea than a bad idea, because the good idea works. I mean, it's a good idea to buy a home, for example. And then people go crazy sometimes. The good idea works, and it works, and it works. Stocks work out better than bonds most of the time. And, after a while, people forget that there were some other limiting conditions. With Edgar Lawrence Smith's book, it was that when bonds yield the same as stocks — which was the case then — the stocks are going to outperform because they have this retained earnings. So stocks started going up in the Twenties and all of a sudden they were selling at 5 or 6 times the prices as when they bought the book. And the original correct perception on his part had experienced changing conditions, but people ... got their confirmation through stock prices. That's what happens in bull markets. People start out thinking stocks are cheap, and then they start thinking stocks have gone up. And, a stock can be a good buy or a bad buy. A bond can be a good buy or a bad buy. It depends on price.

I don't have a problem with guilt about money. The way I see it is that my money represents an enormous number of claim checks on society. It's like I have these little pieces of paper that I can turn into consumption. If I wanted to, I could hire 10,000 people to do nothing but paint my picture every day for the rest of my life. And the GDP would go up. But the utility of the product would be zilch, and I would be keeping those 10,000 people from doing AIDS research, or teaching, or nursing. I don't do that though. I don't use very many of those claim checks. There's nothing material I want very much. And I'm going to give virtually all of those claim checks to charity when my wife and I die.

What the human being is best at doing is interpreting all new information so that their prior conclusions remain intact.