Benjamin Graham is known as the father of value investing because he taught investors to treat stocks as shares of real businesses, not as lottery tickets. His ideas became influential through his books Security Analysis and The Intelligent Investor. Graham argued that careful analysis, patience, and emotional discipline can reduce the risk of investing.
His framework matters because it gives students a structured way to connect market prices with business value.
Value investing begins by estimating a company’s intrinsic value from its assets, earnings, debts, and future prospects. Graham’s key rule was to buy only when the market price is well below that estimated value, creating a margin of safety. This approach uses tools such as balance sheets, income statements, financial ratios, and long-term thinking.
It also teaches that markets can be irrational in the short run but more closely reflect business fundamentals over time.
Key Facts
- Value investing means buying assets for less than their estimated intrinsic value.
- Margin of safety = Intrinsic value - Market price.
- Margin of safety percentage = (Intrinsic value - Market price) / Intrinsic value x 100%.
- P/E ratio = Market price per share / Earnings per share.
- Book value per share = Shareholders' equity / Shares outstanding.
- Graham emphasized that investing should be based on analysis, not speculation or market mood.
Vocabulary
- Intrinsic Value
- Intrinsic value is an estimate of what a business is truly worth based on its assets, earnings, and future cash flows.
- Margin of Safety
- Margin of safety is the gap between an investment’s estimated value and the lower price an investor pays for it.
- Value Investing
- Value investing is a strategy of buying securities that appear underpriced compared with their fundamental worth.
- Mr. Market
- Mr. Market is Graham’s metaphor for the stock market’s changing moods and sometimes irrational prices.
- Book Value
- Book value is the accounting value of a company’s assets minus its liabilities.
Common Mistakes to Avoid
- Confusing a cheap stock with a valuable stock is wrong because a low share price does not prove the business is underpriced.
- Ignoring debt is wrong because high liabilities can reduce a company’s true value and increase the risk of permanent loss.
- Treating intrinsic value as an exact number is wrong because it is an estimate based on assumptions that can change.
- Buying without a margin of safety is wrong because small errors in analysis or unexpected events can turn a promising investment into a loss.
Practice Questions
- 1 A company has an estimated intrinsic value of 50 per share. Calculate the margin of safety in dollars and as a percentage of intrinsic value.
- 2 A stock trades at 4. What is its P/E ratio, and what does that ratio compare?
- 3 Explain why Benjamin Graham would warn investors not to make decisions based only on recent stock price movements.