Bill Fleckenstein says that investors who buy into the stock market at all-time highs are making a grave error. Comparing the current situation to the infamous bubbles of 1999 and 2007, the noted contrarian and short seller says that bulls are ignoring fundamentals at their own peril.
"People are, once again, being fooled," Fleckenstein said on Thursday's episode of "Futures Now." "In the stock mania in 1999, people were bullish because stocks were going up. In 2007, people were bullish because stocks and real estate were going up. They didn't look at—Why are they going up? Is this sustainable? Is this healthy?—and in both cases, it was not."
In this case, the bubble Fleckenstein points to is powered not by tech stocks or real estate, but by the Federal Reserve's quantitative easing program.
(Read more: What is the Fed talking about?)
"Now we have the Fed suppressing the bond market such that rates are ridiculously low, and capital is being misallocated everywhere, and the price of nearly everything is out of whack," Fleckenstein said.
But he says the Fed is starting to lose control already—meaning that stocks could crack even if the Fed continues to buy $85 billion worth of assets each month.