No Woulda, Shoulda, Couldas

Editor's note: As a special bonus to TheStreet.com readers, we will be running an updated version of Jim Cramer's "Twenty-Five Rules of Investing," from his latest book, Real Money: Sane Investing in an Insane World. Here's Rule 13.

Your head matters in this game. You need to have it on right every day if you are going to see opportunities and act on them. Yet so many of us have heads clouded with thoughts that genuinely throw us off target and make us do the wrong thing.

The most damaging recurring thought you can have is this: "If only I ..." -- you can fill in the rest. As in, "If only I had acted sooner on Electronic Arts(ERTS Quote)." Or, "I should have pulled the trigger on Nvidia(NVDA Quote) ahead of that quarter." Or, "I could have made a fortune if I had stayed short that Sun Microsystems(SUNW Quote)."

Don't get hung up on the woulda, shoulda, couldas.

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