The elements weighing on the market range from a crackdown on margin financing to a flood of initial public offerings locking up liquidity. The question now is whether a crash is looming. The Chinese Securities Journal said the Shanghai Composite Index may further "dive to 3,300 points if it can't find support at 4,100", citing an analyst at Guotai Junan Securities.

It was just weeks ago when "everyone" knew the market would power through 6,000 points.

Didn't Peng Wen-sheng, global chief economist at CITIC Securities Co Ltd, say just two weeks ago: "It's too early for investors to talk about a turning point in the market"?

And didn't Minsheng Securities promise that a crash like the one on May 30, 2007 would never recur? (The benchmark index dived 900 points in a few trading days in that "correction" before it headed to a record high of 6,124 points.)

Stock prices follow a "random walk", and history repeats itself. Anyone who claims that they can predict stock prices is either crazy or a prophet.