"The dovish comments from both Fed Chairwoman Janet Yellen and People's Bank of China Governor Zhou Xiaochuan are giving markets a big lift, and in the absence of negative data or news, I imagine this will continue to buoy the markets throughout the session," Erlam said in emailed comments.

Yellen said gradual hikes are likely this year, but that the central bank will move cautiously……. the PBOC governor said he saw "more room" for China to ease policy if the economy stays soft and inflation continues to weaken.

Its just that frightfully simple. If any of the major central banks anywhere on the planet ease or even hint they might, the robo machines and day traders unleash an avalanche of buy orders and the stock averages jerk higher.

Indeed, Zero Hedge captured the motion succinctly this AM. In keeping with Bernanke's inaugural blog revelation that 98% of monetary policy consists of "open mouth" operations, the markets leapt upwards on cue. That is, if central banker jaws are flapping, then buy!