If you are a professional and have confidence, then I would advocate lots of concentration. For everyone else, if it’s not your game, participate in total diversification. The economy will do fine over time. Make sure you don’t buy at the wrong price or the wrong time. That’s what most people should do, buy a cheap index fund and slowly dollar cost average into it.

There are $10 billion mistakes of omission that no one knows about; they don’t show up in the accounting. In 1994 we paid $400 worth of Berkshire stock for a shoe company. The company is now worth 0, but the stock is worth $3.5 billion. So now, I’m happy to see Berkshire go down since it reduces the size of my mistake. In 1973 Tom Murphy offered us NBC for $35 million, but we turned it down. That was a huge mistake of omission.
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Getting turned down by HBS [Harvard Business School] was one of the best things that could have happened to me, bad luck can turn out to be good.
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We did an informal office survey by looking at the total tax footprint versus the total income. I earned 46 million and paid a tax rate of 17.5%. My rate was the lowest, the average was 33%, and my cleaning lady paid 40%. The system is tilted towards the rich. The Forbes 400 total net worth has gone from 220 billion to 1.54 trillion, an increase of 7-to-1. You see in legislature that there is lobbying carried on by the powerful over issues such as the estate tax and carried interest for private equity investments. We need to flatten income and payroll taxes, and those making under $30,000 shouldn’t be bothered.