You need humility to say 'I might be wrong.'

When a stock is selling at a discount to liquidation value per share, a near rock-bottom appraisal, it is frequently an attractive investment.

Unlike return, however, risk is no more quantifiable at the end of an investment that it was at its beginning. Risk simply cannot be described by a single number. Intuitively we understand that risk varies from investment to investment: a government bond is not as risky as the stock of a high-technology company. But investments do not provide information about their risks the way food packages provide nutritional data.

As Buffett has often observed, value investing is not a concept that can be learned and gradually applied over time. It is either absorbed and adopted at once, or it is never truly learned.

Having great clients is the key to investment success.

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.

Investing today may well be harder than it has been at any time in our three decades of existence.