Millions of investors chase Warren Buffett. Tens of thousands attend Berkshire Hathaway's (NYSE:BRK-A) (NYSE:BRK-B) annual shareholder meetings. Wealthy fans bid millions of dollars to have lunch with him. His appearances on CNBC bring trading floors to a halt. People want to know what he's thinking. Why he's different. What secret has made him so much more successful than anyone else.

What's interesting -- and a little ironic -- is that Buffett has never held back what his secret is. As he recently told PBS:

I read a book, what is it, almost 60 years ago roughly, called The Intelligent Investor and I really learned all I needed to know about investing from that book, and particular chapters 8 and 20 … I haven't changed anything since.

One book. Two chapters. Legendary success.
You'd think such precisely guided advice would draw more attention. Not only has Buffett filtered his success down to one book, he's even listed the two specific chapters on which he built his wisdom. He's making this almost embarrassingly easy for us.

What bits of sage advice do these two chapters -- published in 1949 by Buffett's early mentor Ben Graham -- hold? Here are key points from each one.

Chapter 8: The Investor and Market Fluctuations
Markets go up. Markets go down. Most of us accept this fact until we experience the latter, at which time we throw up our hands and consider the whole thing a sham.

That kind of behavior is what Chapter 8 is all about: dealing with market movements, and how fundamental they are to investing success.

We have a tendency to become confident and invest the most money after stocks have logged big gains, and vice versa -- selling in panic after big drops. Two seconds of logical thought will tell you this isn't rational. Yet we do it over and over again.

Buffett built his success on exploiting the market's movements, rather than following them with lemming-like obedience. He bought companies like Coca-Cola (NYSE:KO) and Wells Fargo (NYSE:WFC) when the market wanted nothing to do with them. He then sat on his hands and laughed when companies like Microsoft (NASDAQ:MSFT) and (NASDAQ:AMZN) soared during the dot-com boom, ignoring heckles about his technophobic incompetence. It's truly as simple as "being greedy when others are fearful, and fearful when others are greedy."

Here's how Graham puts it in Chapter 8:                                                   

The true investor scarcely ever is forced to sell his shares, and at all other times he is free to disregard the current price quotation. He need pay attention to it and act upon it only to the extent that it suits his book, and no more. Thus the investor who permits himself to be stampeded or unduly worried by unjustified market declines in his holdings is perversely transforming his basic advantage into a basic disadvantage. That man would be better off if his stocks had no market quotation at all, for he would then be spared the mental anguish caused him by other persons' mistakes of judgment.

Chapter 20: Margin of Safety as the Central Concept of Investment
Graham opens Chapter 20 with a potent message:

In the old legend the wise men finally boiled down the history of mortal affairs into the single phrase, 'This too will pass.' Confronted with a like challenge to distill the secret of sound investment into three words, we venture the motto, MARGIN OF SAFETY.

We have an overwhelming urge to expect certainty, but live in a world that is anything but. Forward-looking projections of a stock's value are based on assumptions, prone to wild miscalculations and unforeseen events. And by prone, I mean 100% assured.

There's only one surefire solution to this: Pay far less for stocks than your estimate of value, leaving room for error. That's a margin of safety. It's giving yourself room to be wrong, knowing that you probably will be. Think a company is worth $50 a share? Great. Don't pay more than $25 for it. Think a company could earn $2 per share next year? Great. Set yourself up so you'll profit if it only makes a buck. There has to be a wide range of acceptance between the projected and the potential.

One stock that might epitomize the opposite of a margin of safety is Visa (NYSE:V). Visa is a great company, to be sure, exploiting a global consumer shifting from paper to plastic transactions. But it currently trades at more than 22 times 2009 earnings. My calculations of growth show this is probably what the company is worth if everything goes according to plan.

But what if everything doesn't? What if growth hits a speed bump? What if management drops the ball? What if consumer spending takes a sustained nosedive? What if, what if, what if -- that's the basis of a margin of safety. There has to be sizable room for error.

Moving on
These lessons might seem basic and dull. They are. Yet too many investors fail to implement them. Buffett obviously isn't the only one who's read The Intelligent Investor -- he's simply put its lessons and theories to work in a habitual manner.

Our Motley Fool Inside Value team strives to put these basic values to work with all of its recommendations, which are currently outperforming the market by an average of four percentage points each. To see what we're recommending right now, you can try the service free for 30 days. Click here to get started. There's no obligation to subscribe.

Fool contributor Morgan Housel owns shares of Berkshire Hathaway. and Berkshire Hathaway are Motley Fool Stock Advisor picks. Berkshire Hathaway, Coca-Cola, and Microsoft are Motley Fool Inside Value selections. Coca-Cola is a Motley Fool Income Investor recommendation. The Fool owns shares of Berkshire Hathaway, and has a disclosure policy.