Dow plunges 500 points

Stocks plunged Thursday, with the Dow tumbling 500 points just before the close, as fear about the global economy spooked investors.

"The conventional wisdom on Wall Street was that the economy was growing -- that the worst was behind us," said Peter Schiff, president of Euro Pacific Capital. "Now what people are realizing is the stimulus didn't work, and we may be headed back to recession."