Even the best stock pickers make mistakes.

But it's not by an specific wrongdoing, Billionaire investor and Fisher Investments founder and chairman Ken Fisher told TheStreet founder Jim Cramer. Rather, it's just the human condition.

"From the Fed, to the person who's 65 and thinks they're old...What is it about people that they constantly make mistakes?" Cramer asked Fisher.

"It's real simple," Fisher answered, followed by an impression of a jungle primate. "Monkeyism."

Fisher has everything you need to know about the forces driving the market, even when you don't realize they are. 

Watch Ken Fisher's and Jim Cramer's Full Interview, just click here to sign in for free.

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