Invest in businesses any idiot could run, because someday one will.

Your ultimate success or failure will depend on your ability to ignore the worries of the world long enough to allow your investments to succeed.

When people discover they are no good at baseball or hockey, they put away their bats and their skates and they take up amateur golf or stamp collecting or gardening. But when people discover they are no good at picking stocks, they are likely to continue to do it anyway.

Never buy anything that you can't illustrate on the back of a napkin.

There's no use diversifying into unknown companies just for the sake of diversity. A foolish diversity is the hobgoblin of small investors. That said, it isn't safe to own just one stock, because in spite of your best efforts, the one you choose might be the victim of unforeseen circumstances. In small portfolios, I'd be comfortable owning between three and ten stocks.

The junior high schools and high schools of America have forgotten to teach one of the most important courses of all. Investing.

You only need a few good stocks in your lifetime. I mean how many times do you need a stock to go up ten-fold to make a lot of money? Not a lot.