"Fraud aside, we should have known better. We should have known that investments in transforming technologies have often proved unrewarding for investors. In the 1850s, the railroad was widely expected to greatly increase the efficiency of communications and commerce. It certainly did so, but it did not justify the prices of railroad stocks, which rose to enormous speculative heights before collapsing in August 1857. A century later, airlines and television manufacturers transformed our country, but most of the early investors lost their shirts. The key to investing is not how much an industry will affect society or even how much it will grow, but rather its ability to make and sustain profits. And history tells us that eventually all excessively exuberant markets succumb to the laws of gravity. The consistent losers in the market, from my personal experience, are those who are unable to resist being swept up in some kind of tulip-bulb craze. It is not hard, really, to make money in the market. As we shall see later, an investor who simply buys and holds a broad-based portfolio of stocks can make reasonably generous long-run returns. What is hard to avoid is the alluring temptation to throw your money away on short, get-rich-quick speculative binges."