One of the worst things you can do after you win is to start losing. The worst thing is to give back all your spoils, Jim Cramer told listeners on his

"RealMoney" radio show Thursday.

Cramer related a story about a visit to a casino with his mother 25 years ago to illustrate why he changed his thinking on oil this week. They had won $100 by 10:30 a.m., at which time his mother led her protesting son out of the casino and bought a $100 sweater. She wore it for years.

"I got a lifetime's worth of financial knowledge out of

that situation," Cramer said. "We had gambled, and we had won. Worth a gazillion sweaters."

Whether gambling or investing, discipline is discipline, Cramer said. "I came to play and to win. I believe to say that oil could double, to say that oil could go from 5% to 10% of the

S&P 500

over a couple of years, and then to have that happen, and to then

keep pressing after you have won

, seems foolish."

Cramer mentioned

Jarden

(JAH)

, a small appliance maker.

"It's better to be lucky than good," said Cramer. "I think Jarden is about to get real lucky." Cramer noted the company is in a war for shelf space at stores like

Wal-Mart

(WMT) - Get Report

with its two competitors,

Applica

( APN) and

Salton

( SFP).

Cramer says because Applica and Salton have overextended themselves, they're at risk of going bankrupt. Wal-Mart will likely be concerned about those two companies' ability to deliver products in time for Christmas.

"That means that even if Jarden just stands still, it wins," he said. "It doesn't need to be wide-eyed and grow the business by leaps and bounds. It just needs to show up. And show up it will."

A listener asked Jim to expound on energy. Cramer said until this week, he had a tremendous amount of energy in his portfolio, and he now thinks energy has peaked.

"The great trade in energy... is now probably wrong," said Cramer. Fourteen percent of his portfolio was in energy, which would mean oil would have to go to $80 to achieve the performance he expects, and he doesn't think it will.

Again, Cramer reiterated the importance of discipline, with the energy sector having grown to 10% of the S&P 500. "I'd rather be right, even if it means I have to contradict a view that I held in the last few days."

In his "Stump Cramer" segment where listeners ask about obscure and semi-obscure stocks, Cramer was asked about

Hoku Scientific

( HOKU),

LanOptics

(LNOP)

,

Immunicon

( IMMC),

Insteel Industries

(IIIN) - Get Report

,

PowerDsine

( PDSN) and

Airtrax

(AITX)

. Cramer said Hoku, which is involved in fuel cells, seemed "interesting." He thought LanOptics was a "dynamite Israeli company," which is just now beginning to have a revenue breakout.

Cramer was stumped by Immunicon, Insteel Industries and Airtrax. However, Cramer advised caution with regard to speculative stocks like Airtrax. Take care of retirement first, he said. After you've taken care of retirement, it's fine to build a "mad money" portfolio where 20% is allocated to speculation.

Finally, commenting on

Google

(GOOG) - Get Report

, Cramer said everyone has a "curmudgeon value-investor demon" inside them that must be exorcized occasionally in order not to miss investment opportunities. The curmudgeon says you should never buy a stock for a multiple of more than 20 times earnings. But, the mutual fund manager's short-hand rule is to pay twice the growth rate for a growth stock.

Google has been growing at a rate of about 35%. Paying twice Google's growth rate would yield a P/E multiple of 70. Cramer believes Google is capable of earning $9 a share, which would equate to a stock price of $630.

While that may sound ridiculous, Cramer said, consider that

Yahoo!

(YHOO)

is trading at a P/E of about 70, with a growth rate less than Google's.

Whole Foods

( WFMI) is trading at almost a 70 multiple, with only two-thirds the growth rate of Google's.

What's more, in a slowing economic environment, Cramer believes a stock like Google, which doesn't have much economic sensitivity, is worth a super-premium, perhaps three times its growth rate. That would equate to a stock price of $810.

The bottom line, Cramer says, is that even if Google's growth rate slows to 25% next year and one pays a multiple of twice its growth rate -- and even if Google only earns $7 a share -- 50 times $7 equals a stock price of $350. And, that is Cramer's target.

"I think you should use the weakness to go buy some Google."

At the time of publication, Cramer was long Yahoo!.

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

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