Although we deal with probabilities and expectations, the actual results can deviate substantially from such expectations, particularly on a short-term basis.

One of the ironies of the stock market is the emphasis on activity. Brokers, using terms such as 'marketability' and 'liquidity,' sing the praises of companies with high share turnover... but investors should understand that what is good for the croupier is not good for the customer. A hyperactive stock market is the pick pocket of enterprise.

Investors should be skeptical of history-based models. Constructed by a nerdy-sounding priesthood using esoteric terms such as beta, gamma, sigma and the like, these models tend to look impressive. Too often, though, investors forget to examine the assumptions behind the models. Beware of geeks bearing formulas.

You’d get very rich if you thought of yourself as having a card with only twenty punches in a lifetime, and every financial decision used up one punch. You’d resist the temptation to dabble. You’d make more good decisions and you’d make more big decisions.

You can lose leverage, and it's the only way a smart guy can go broke.

The Fed is the greatest hedge fund in history.

Risk comes from not knowing what you're doing.