The Parable of "Mr. Market"
Graham told a brilliant parable: imagine you have a wildly moody business partner named "Mr. Market." Every day he comes and quotes you a price — sometimes elated and quoting high, sometimes despondent and willing to sell cheap. You are free to ignore him entirely, or to buy when he pessimistically sells cheap and sell when he feverishly quotes high. His quote is an opportunity offered to you, not a command. This parable makes the matter of "how to face the market’s madness" as clear as can be — and it is still the first lesson for every value investor today.