Graham

• Individuals who cannot master their emotions are ill-suited to profit from the investment process.
• The investor's chief problem - and even his worst enemy - is likely to be himself.
• Know the asking price. Even the best company can be a  poor  investment at  the wrong (too high) price.
• Have the courage of your knowledge and experience. If you have formed a conclusion from the facts and if you know your judgment is sound, act on it - even though others may hesitate or differ. You are neither right nor wrong because the crowd disagrees with you. You are right because your data and reasoning are right.
• Obvious prospects for physical growth in a business do not translate into obvious profits for investors.
• Operations for profit should be based not on optimism but on arithmetic.
• Basically, 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. At other times he will do better if he forgets about the stock market and pays attention to his dividend returns and to the operating results of his companies.
• The risk of paying too high a price for good-quality stocks - while a real one - is not the chief hazard confronting the average buyer of securities. Observation over many years has taught us that the chief losses to investors come from the purchase of low-quality securities at times of favorable business conditions. The purchasers view the current good earnings as equivalent to "earning power" and assume that prosperity is synonymous with safety.
• 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.