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

Speculative stock movements are carried too far in both directions, frequently in the general market and at all times in at least some of the individual issues.

Mr. Market's job is to provide you with prices; your job is to decide whether it is to your advantage to act on them. You no not have to trade with hime just because he constantly begs you to.

It is our argument that a sufficiently low price can turn a security of mediocre quality into a sound investment opportunity - provided that the buyer is informed and experienced and he practices adequate diversification. For, if the price is low enough to create a substantial margin of safety, the security thereby meets our criterion of investment.

Even defensive portfolios should be changed from time to time, especially if the securities purchased have an apparently excessive advance and can be replaced by issues much more reasonable priced.

In the short run, the market is a voting machine, but in the long run it is a weighing machine.

The value of any investment is, and always must be, a function of the price you pay for it.