Benjamin Graham

What Is Benjamin Graham?

Benjamin Graham was an economist, investor, and professor who is widely regarded as the father of value investing. He taught finance at Columbia Business School and wrote books that influenced generations of investors. His two most influential works are "Security Analysis," written with David Dodd and published in 1934, and "The Intelligent Investor," published in 1949.

Core Ideas

Graham argued that a stock represents partial ownership of a business, and its price should be judged against what that business is actually worth. He called this underlying worth intrinsic value. Market prices, he observed, often move away from intrinsic value because of emotion and short-term sentiment. To illustrate this, he described a moody business partner named "Mr. Market" who offers to buy or sell shares at different prices each day. An investor could act on those offers when they were far from underlying value, but was free to ignore them.

Graham emphasized buying with a margin of safety, meaning paying meaningfully less than the estimated intrinsic value. This gave room for errors in judgment or bad luck. He relied heavily on fundamental analysis of financial statements, examining measures such as book value and earnings. He was skeptical of paying high prices for uncertain future growth. Ratios like the price-to-earnings ratio were part of his approach to comparing prices with earnings.

Why It Matters to Investors

Graham's ideas remain a reference point for disciplined stock selection. Students of his work often focus on the gap between price and value, on diversification, and on controlling their own reactions to market swings. His student Warren Buffett later became one of the best-known investors in the world and credited Graham's teaching as a major influence.

Graham's approach is not the only way to invest. Critics point out that markets have changed since his era, that some of his valuation methods are harder to apply today, and that value strategies have gone through long periods of underperformance.

Limitations

Applying Graham's methods requires judgment, and estimates of intrinsic value can be wrong. His ideas are presented here for educational purposes and are not a recommendation to buy or sell any security.