Cup of Confucius

Name used in Asia for a Pythagorean Cup, i.e. a cup that looks like a normal drinking cup, except that the bowl has a hollow central column in it, in the Asian version often a Chinese bearded figure that represents Confucius (fig.). The cup works on the principle of communicating vessels. The Chinese figure or central column is positioned directly over the stem of the cup which has a tiny hole at the bottom that is connected to a small open pipe that runs from this hole almost to the top of the central column. At the foot of the central column in the bottom of the bowl, is another tiny hole through which the liquid will rise inside the hollow central column to the same level as in the cup. When the cup is filled partially, nothing happens and the cup functions normally, as long as the liquid does not rise above the top of the open pipe in the chamber. However, if the level rises to the over the top of the open pipe inside the chamber of the central column, the liquid spills through the first chamber and out of the bottom of the cup through the second pipe that is connected to the bottom of the central column. Hydrostatic pressure then creates suction which pulls the stream of liquid into the syphon, thus emptying the entire cup through the base. Legend has it that when Confucius almost died of hunger and thirst in the desert, he was given a cup to scoop water from a well, but when he scooped up a full cup of water it turned out to be empty. The cup only held the water if it was partially full. This corresponds to an ancient Chinese practice. In China, tea is a symbol for friendship and camaraderie (fig.), and Chinese people always use tea to welcome guests in their home, filling a cup of tea for only seven-tenths of its capacity, believing that the other thirty percent will be filled with friendship and affection, which is in line with Confucius' wisdom that propagates to behave toward everyone as if receiving a great guest, and his doctrine that humans need to control their behaviour by keeping balance and not live in extremes. Also referred to as Confucius Cup, and in the West, it is also known by the names Pythagoras Cup, Greedy Cup, Cup of Justice, and Tantalus Cup. 回