In the late Joseon Dynasty in Korea, there was a potter named Woo Myeong-ok in a mountain village of Gangwon-do Province. He wanted to make beautiful porcelain beyond the earthenware, so he entered the Bunwon, which produced porcelain for the royal family, with a great ambition. There he learned hard from his teacher and his skill finally reached artistic mastery. As a result, he could earn tremendous wealth and fame. However, forgetting his first resolution, he became arrogant and led a dissolute life. After he lost everything he had, he came to his senses.
Afterwards, he kept his mind and body clean and made a cup with all his strength. The work was called a “Cup Warning of Overflow.” When the cup is more than three quarters full, all the liquid in it spills out of the bottom. As there is a ∩-shaped central column in the cup, when the cup is filled beyond the column, the water flows into a hole at the bottom of the column and drains out.
Today, this cup is regarded as high-quality, probably because it gives us a lesson: “Greed loses everything.”