Central to Zweig's core beliefs was his investing thesis of "don't fight the Fed." Meaning, when the Fed raises rates, investors must be aware that the wind has gone from your back to your face. He found that interest rate movements and Federal Reserve policy were dominant factors in determining the overall direction of the market. So when the Fed tightened, it was bearish for stocks and when it cut rates it was bullish.
But that doesn't mean that it's game over now just because the Fed has tightened.
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Another principal that Cramer described is to be flexible and non-dogmatic. He did not want investors to leave the market when the Fed started raising rates — he just wanted them to be less positive.
"So now I'm less positive. I can't help it. Marty made me too much money with that philosophy and I can't go against it," Cramer said.
Ultimately, Zweig taught Cramer not to fight the Fed, but to be flexible at the same time. Many stocks are still accessible and gains are obtainable if the proper homework is done.
Cramer recommended keeping an eye out for good companies and waiting until their stocks dip to bargain prices. Just don't be as aggressive as you once were, and don't let gains turn into losses because of overconfidence and greed.