The Defensive Analyst
You start from the balance sheet, not the story. A price far below what the assets are worth is your entire thesis, and you would rather own twenty boring bargains than one exciting growth company. Being right matters less to you than not being wrong badly.
Before any buy, write down the number you think the business is worth and the price you will pay. If you cannot write both, you are not ready.
Buy at a demonstrable discount to measurable value, spread across enough names that no single mistake can hurt you.
The Intelligent Investor (1949), ch. 20 — "Margin of Safety"
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