Vice-President Xi Jinping, the presumed heir of President Hu Jintao, vanished from public view for two weeks this month, and his meetings with several foreign leaders were cancelled. As is usual in the murky world of Chinese politics, many chose not to believe the statements citing a back injury, and all sorts of rumours swirled. In time, the truth - if there is such a thing in the mainland - about his disappearance may be revealed, but for now most people are just relieved to see a healthy looking Xi back in the limelight.

The Wanli Emperor of the Ming dynasty, who reigned from 1572 to 1620, must surely hold the record for the length of time that a state leader has been absent from duty. For 30 years, from 1589 until a couple of years before his death, he shut himself up in his palace and refused to communicate with his government. At a time when almost all executive power was vested in the emperor, Wanli's neglect almost crippled China. For three decades, reports made to the throne were not answered or acted upon, criminal cases were not heard and officials simply left their posts with no replacements appointed.

It's a testament to the strength of the bureaucracy that the empire didn't im-plode. Explanations about Wanli's strange behaviour range from opium addiction to clinical depression, but none have ever been verified.