Barriers to entry in this industry are very significant. In addition to negotiating thousands of contracts with data providers and gaining access to several hundred thousands of data sites, an entrant would have to overcome investments in intellectual property.

If you look at a company’s balance sheet, book value is the difference between the company’s assets and its liabilities — it is the company’s equity.

Book value in today’s economy is even less relevant for most companies. The value that you don’t see on Apple’s balance sheet is that sparkle in Apple customers’ eyes when they use the company’s products. That sparkle is the intangible good that Apple created by building (often) revolutionary products.

Value investing doesn’t do as well when the punch bowl is spiked with euphoria and everyone only looks up. It is when the punch bowl is taken away and investors start looking down that value investing, or simply common sense, does well.

A bull market makes you feel smarter than you are, the same way a bear market makes you feel dumber than you are.

Buy and hold (never a great idea in any environment) absolutely must be replaced with buy and sell.

As my income went up, instead of buying myself things, I turned to buying time and experiences. It’s a trade-off.