There seems to be an unwritten rule on Wall Street: If you don't understand it, then put your life savings into it. Shun the enterprise around the corner, which can at least be observed, and seek out the one that manufactures an incomprehensible product.

You have to let the big ones make up for your mistakes.

If you go to Minnesota in January, you should know that it's gonna be cold. You don't panic when the thermometer falls below zero.

There is always something to worry about. Avoid weekend thinking and ignoring the latest dire predictions of the newscasters. Sell a stock because the company's fundamentals deteriorate, not because the sky is falling.

Investing in stocks is an art, not a science, and people who've been trained to rigidly quantify everything have a big disadvantage.

If you're prepared to invest in a company, then you ought to be able to explain why in simple language that a fifth grader could understand, and quickly enough so the fifth grader won't get bored.

Although it's easy to forget sometimes, a share is not a lottery ticket... it's part-ownership of a business.