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

Sometimes buying early on the way down looks like being wrong, but it isn't.

Value investors will not invest in businesses that they cannot readily understand or ones they find excessively risky. Hence few value investors will own the shares of technology companies. Many also shun commercial banks, which they consider to have unanalyzable assets, as well as property and casualty insurance companies, which have both unanalyzable assets and liabilities.

Ultimately, nothing should be more important to investors than the ability to sleep soundly at night.

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.

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.

I think Buffett is a better investor than me because he has a better eye toward what makes a great business. And when I find a great business I'm happy to buy it and hold it. Most businesses don't look so great to me.