The most realistic distinction between the investor and the speculator is found in their attitude toward stock-market movements. 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. Market movements are important to him in a practical sense, because they alternately create low price levels at which he would be wise to buy and high price levels at which he certainly should refrain from buying and probably would be wise to sell.

Observation over many years has taught us that the chief losses to investors come from the purchase of low-quality securities at times of good business conditions. The purchasers view the good current earnings as equivalent to 'earning power' and assume that prosperity is equivalent to safety.

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

Price fluctuations have only one significant meaning for the true investor. They provide him with an opportunity to buy wisely when prices fall sharply and to sell wisely when they advance a great deal.

Investing is most intelligent when it is most businesslike.

Never buy a stock because it has gone up or sell one because it has gone down.

Even with a margin of safety in the investor's favor, an individual security may work out badly. For the margin guarantees only that he has a better chance for profit than for loss - not that loss is impossible. But as the number of such commitments is increased the more certain does it become that the aggregate of the profits will exceed the aggregate of the losses.