The Intelligent Investor: “Margin of Safety” as the Central Concept of Investment

Chapter 20 - “Margin of Safety” as the Central Concept of Investment
A single quote by Graham on page 516 struck me:

Observation over many years has taught us that the chief losses to investors come from the purchase of low-quality securities at times of favorable business conditions.

Basically, Graham is saying that most stock investors lose money because they invest in companies that seem good at a particular point in time, but are lacking the fundamentals of a long-lasting stable company.

This seems obvious on the surface, but it’s actually a great argument for thinking more carefully about your individual stock investments. If most of your losses come from buying companies that seem healthy but really aren’t, isn’t that a profound argument for carefully studying any company you might invest in?

Graham takes this point a step further, arguing that diversification is strongly correlated with margin of safety. In effect, Graham states that you introduce some additional margin of safety into your portfolio when you own a widely diverse array of value stocks that each have significant margin of safety.

Graham’s final note is pretty simple: investors get in trouble when they abandon their basic principles in the heat of the moment. One must approach investing with a set of fundamental principles and not abandon them in the heat of the moment.

Commentary on Chapter 20
Zweig closes out this final chapter by arguing that psychology is a major part of investing, one that many people overlook in the rush to find the big bargain. He goes so far as to argue that people are the primary risk in their own investing - poor decision making and abandonment of principles results in far more loss than an investment gone wrong.

Zweig actually ties this to Pascal’s wager, a famous suggestion by the French philosopher Blaise Pascal in which he argues that, since God’s existence cannot be determined through reason, one should behave as though God does exist, since living in that way (as opposed to living as though God does not exist) provides much more gain than loss. Similarly, since one cannot prove what will happen in the future with investments, we’re better off living by our investing principles than playing it by ear.


http://www.thesimpledollar.com/2009/02/27/the-intelligent-investor-margin-of-safety-as-the-central-concept-of-investment/