With uncertainty shaking European and U.S. stock markets, investors must take the "leap of faith that you’re willing to risk some capital, that we’re going to muddle our way through this and find the companies that are hitting new highs," Robert Doll, BlackRock chief equity strategist, told CNBC Tuesday.

"Good companies that produce good results will be rewarded in the marketplace, and you just have to work a little harder to find them and maybe have a little more patience," he said. "I think the 'short-termism' has spooked a lot of people."

He thinks markets have priced in a possible Greek default, as long as it's "an organized default, not a chaotic one."

Similarly, U.S. markets have priced in any possible action by the Federal Reserve , following its two-day meeting ending Wednesday.     

Doll said the Fed has "got to do a little something to tip the hat to the markets. If they do nothing...I don’t think the markets are going to like that very much—but I don’t think he has to do a lot," he said.

One thing the Fed could do would be "traditional QE3, , which virtually nobody’s talked about. [Bernanke will] save that for a rainy day if he needs it. Let’s hope he doesn’t."

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Disclosures:

Disclosure information was not available for Robert Doll or his company.

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