An investor calculates what a stock is worth, based on the value of its businesses.

The intelligent investor is a realist who sells to optimists and buys from pessimists.

Losing some money is an inevitable part of investing, and there's nothing you can do to prevent it. But to be an intelligent investor, you must take responsibility for ensuring that you never lose most or all of your money.

Confusing speculation with investment is always a mistake.

We are convinced that the intelligent investor can derive satisfactory results from pricing of either type (market timing or fundamental analysis via price). We are equally sure that if he places his emphasis on timing, in the sense of forecasting, he will end up as a speculator and with a speculator's financial results." And "The speculator's primary interest lies in anticipating and profiting from market fluctuations. The investor's primary interest lies in acquiring and holding suitable securities at suitable prices.

As in roulette, same is true of the stock trader, who will find that the expense of trading weights the dice heavily against him.

When somebody asserts that a stock has an earning power of so much, I am sure that the person who hears him doesn't know what he means, and there is a good chance that the man who uses it doesn't know what it means.