Value investing is at its core the marriage of a contrarian streak and a calculator.

My experience is that short sellers do far better analysis than long buyers because they have to. The market is biased upward over time-as the saying goes, stocks are for the long run.

One of the biggest challenges in investing is that the opportunity set available today is not the complete opportunity set that should be considered. Limiting your opportunity set to the one immediately at hand would be like limiting your spouse to the students you met in high school

It is always easiest to run with the herd; at times, it can take a deep reservoir of courage and conviction to stand apart from it. Yet distancing yourself from the crowd is an essential component of long-term investment success.

Risk is not inherent in an investment; it is always relative to the price paid. Uncertainty is not the same as risk. Indeed, when great uncertainty - such as in the fall of 2008 - drives securities prices to especially low levels, they often become less risky investments.

People should be highly sceptical of anyone's including their own, ability to predict the future, and instead pursue strategies that can survive whatever may occur.

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.