From Richard Russell:

Primary trends can be likened to the power of the ocean tides. Build a sand castle against the ocean tide, and the first wave will wash your castle away. Build a cement wall against the tide, and in a matter of years the cement wall will be reduced to sand and rubble…primary trends, one way or another, go to completion. Or to put it another way, a primary trend will go to completion, no matter what..I said from the beginning, “let the bear market fully express itself.” One way or another it will express itself regardless of the wishes of Washington or the Fed or the Treasury. Interfering with the primary trend will just drag out the situation and make it worse — it will be turning a menace into a Frankenstein…According to Dow Theory, neither the depth nor the duration of a bear market can be predicted in advance. In this bear market, the Dow could fall to 4,000 or 400. I honestly don’t know the answer. In my experience, primary trend tend to carry further than anyone expects. I do know this — yesterday the following broke below their June lows — the Dow, the Transports, the NYSE Composite (which includes ALL NYSE stocks), the S&P Composite, the NASDAQ and the Russell 2000. Any way you look at it, that’s bad action. Maybe just as bad, new lows on the NYSE surged to 164. Hundreds of stocks are breaking down, and even more are hovering just above their 52-week lows. The lower depths of this market are opening up like a giant graveyard. It is said that in a big bear market, stocks return to their original homes — Wall Street.”

Can it happen? Yes. Does anyone know for sure? No. Follow trends.