Rule No. 21: Be a TV Critic - TheStreet

Editor's note: Jim Cramer's new book,

Real Money: Sane Investing in an Insane World

, is available in selected bookstores now. As a special bonus to

RealMoney

readers, we will be running Cramer's "Twenty-Five Rules of Investing." For more about the new book and to order it, click here. Today, we present Cramer's twenty-first rule of investing. Read more about his rules:

    Pigs Get Slaughtered It's OK to Pay the Taxes Don't Buy All at Once Buy Damaged Stocks Diversify to Control Risk Do Your Homework Don't Panic Buy Best-of-Breed Defend Some Stocks Don't Bet on Bad Stocks Don't Own Too Many Names Cash Is for Winners No Woulda, Shoulda, Couldas Expect Corrections Watch Bonds Don't Subsidize Losers Check Hope at the Door Be Flexible Quit When Execs Do Patience Is a Virtue

Do you know how financial television really works?

I'll tell you. At times, it can just be a gigantic booking machine. That's right, people are scrambling to get money managers on who can talk, almost regardless of how good they are. And lots of times, executives say whatever they want on air, knowing that they can get away with it.

I accept this as a given. I accept that what I hear on television is probably right, but no more than that. That's the world in which we live. That's the reason I follow this tenet:

Just because someone says it on TV doesn't make it so.

Not long ago, a money manager came on television and knocked down

Sirius

(SIRI) - Get Report

by saying some negative things about it, some of which were true. I accepted the fact that he was short it and that he probably shorted the stock right before he went on and that probably what he said wasn't right. Did you think he was right?

I think you are naive if you simply believe what you hear. The vetting process to get on television simply isn't all that rigorous. When a manager says he likes

EMC

(EMC)

or

Sun Microsystems

(SUNW) - Get Report

, do you ask yourself where he bought it? Do you think he might be selling it?

When someone comes on and says that

Elan

(ELN)

is a buy, do you think, "He's really stuck in that pig"?

If you answered yes to these inquiries, then you are armed for the daily chatter.

James J. Cramer is a director and co-founder of TheStreet.com. He contributes daily market commentary for TheStreet.com's sites and serves as an adviser to the company's CEO. Outside contributing columnists for TheStreet.com and RealMoney.com, including Cramer, may, from time to time, write about stocks in which they have a position. In such cases, appropriate disclosure is made. To see his personal portfolio and find out what trades Cramer will make before he makes them, sign up for Action Alerts PLUS by

clicking here. While he cannot provide personalized investment advice or recommendations, he invites you to send comments on his column to

jjcletters@thestreet.com. Listen to Cramer's RealMoney Radio show on your computer; just click

here. Watch Cramer on "Mad Money" at 6 p.m. EST weeknights on CNBC. Click

here to order Cramer's latest book, "Real Money: Sane Investing in an Insane World," click

here to get his second book, "You Got Screwed!" and click

here to order Cramer's autobiography, "Confessions of a Street Addict."

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