Andrew Kessler, a former hedge fund manager who now authors financial books, urges stock investors to sit tight, better times are on the horizon.

“Stick it out until February,” he told CNBC.

“No one rings a bell at the top of market or the bottom. Trading is irrational, with tax loss selling, mutual fund redemptions, hedge fund redemptions and margin calls.”

In this kind of environment, you have to “forget trying to explain every blip in the market,” Kessler says.

“You just have to go away and let the market do what it’s doing. If you own stocks, sell them, take the tax loss and buy them back in 30 days.”

And what will be the outcome of that strategy?

“You’re going to get a decade’s worth of performance in a week’s time, as the pressure lifts after all this forced selling,” Kessler argues

But the timing is unpredictable, he says. “It could happen five days, five weeks or five years from now.”

Bottom line: “Hunker down and ignore day-to-day gyrations,” Kessler says.

Jeremy Grantham, director of GMO, a Boston investment firm that manages more than $140 billion, has been bearish on stocks for 14 years — until now.

“With the S&P at 900, stocks are cheap in the U.S. and cheaper overseas. We will therefore be steady buyers at these prices,” he told Kiplinger.com.