To achieve long-term success over many financial market and economic cycles, observing a few rules is not enough. Too many things change too quickly in the investment world for that approach to succeed. It is necessary instead to understand the rationale behind the rules in order to appreciate why they work when they do and don't when they don't.

Things that have never happened before are bound to occur with some regularity. You must always be prepared for the unexpected, including sudden, sharp downward swings in markets and the economy. Whatever adverse scenario you can contemplate, reality can be far worse.

Do not trust financial market risk models. Despite the predilection of some analysts to model the financial markets using sophisticated mathematics, the markets are governed by behavioral science, not physical science.

As value investors, our business is to buy bargains that financial market theory says do not exist. We've delivered great returns to our clients for a quarter century-a dollar invested at inception in our largest fund is now worth over 94 dollars, a 20% net compound return. We have achieved this not by incurring high risk as financial theory would suggest, but by deliberately avoiding or hedging the risks that we identified.

Right at the core, the mainstream has it backwards. Warren Buffett often quips that the first rule of investing is to not lose money, and the second rule is to not forget the first rule. Yet few investors approach the world with such a strict standard of risk avoidance.

While it might seem that anyone can be a value investor, the essential characteristics of this type of investor-patience, discipline, and risk aversion-may well be genetically determined.

As Graham, Dodd and Buffett have all said, you should always remember that you don't have to swing at every pitch. You can wait for opportunities that fit your criteria and if you don't find them, patiently wait. Deciding not to panic is still a decision.