Pressure to produce over the short term - a gun to the head of everyone - encourages excessive risk taking which manifests itself in several ways - fully invested posture at all times, the use of leverage, and a market centric orientation that makes it difficult to stand apart from the crowd and take a long term perspective.

The latest trade of a security creates a dangerous illusion that its market price approximates its true value. This mirage is especially dangerous during periods of market exuberance. The concept of "private market value" as an anchor to the proper valuation of a business can also be greatly skewed during ebullient times and should always be considered with a healthy degree of skepticism.

Rather, risk is a perception in each investor's mind that results from analysis of the probability and amount of potential loss from an investment. If an exploratory oil well proves to be a dry hole, it is called risky. If a bond defaults or a stock plunges in price, they are called risky. But if the well is a gusher, the bond matures on schedule, and the stock rallies strongly, can we say they weren't risky when the investment after it is concluded than was known when it was made.

When all feels calm and prices surge, the markets may feel safe; but, in fact, they are dangerous because few investors are focusing on risk.

Literally draw a detailed map-like an organization chart-of interlocking ownership and affiliates, many of which were also publicly traded. So, identifying one stock led him to a dozen other potential investments. To tirelessly pull threads is the lesson that I learned from Mike Price.

Beware leverage in all its forms. Borrowers - individual, corporate, or government - should always match fund their liabilities against the duration of their assets. Borrowers must always remember that capital markets can be extremely fickle, and that it is never safe to assume a maturing loan can be rolled over. Even if you are unleveraged, the leverage employed by others can drive dramatic price and valuation swings; sudden unavailability of leverage in the economy may trigger an economic downturn.

In investing it is never wrong to change your mind. It is only wrong to change your mind and do nothing about it.