A pair of blanc de chine 'Trick cups', Qing dynasty.

Trick Cups or Gong Dao Bei (dont be greedy cuporfairness cup`) were wine cups where the wine would drain over the lap of heavy drinker. They illustrate the classical Chinese paradigm that modesty brings gain and arrogance results in loss. If you fill the cup to the top, taking more than your share, every drop will drain out onto your lap through a hole in the bottom, but if you are modest and only fill the cup half full you will be able to drink normally. The earliest cups of this type were made during the Song Dynasty (960-1279) but most are 18th or 19th century.