Naman Lazarus's Key Ideas from The Intelligent Investor
by Benjamin Graham

One can simply not avoid speculation. In most periods the investor must recognize the existence of a speculative factor in his common-stock holdings. It is his task to keep this component within minor limits, and to be prepared financially and psychologically for adverse results that may be of short or long duration.

Some speculation is necessary and unavoidable. There is intelligent speculation as there is intelligent investing. But there are many ways in which speculation may be unintelligent. Of these the foremost are:

(1) speculating when you think you are investing.

(2) speculating seriously instead of as a pastime, when you lack proper knowledge and skill for it.

(3) risking more money in speculation than you can afford to lose.

Speculation is always fascinating, and it can be a lot of fun while you are ahead of the game. If you want to try your luck at it, put aside a portion—the smaller the better—of your capital in a separate fund for this purpose. Never add more money to this account just because the market has gone up and profits are rolling in. (That’s the time to think of taking money out of your speculative fund.)