原: 孔子家語, 三恕/4 中
孔子曰：吾聞宥坐之器，虛則欹，中則正，滿則覆。

有坐之器 (유좌지기,yǒuzuòzhīqì,ゆうざの－き), nearby [of] bowl
Moderation in all things. Heart should not be emptied nor be overflowing.

Gong-ja was visiting an ancestral shrine (祠堂) of Hwan-gong (桓公) of the country of Ju (周). Inside was a bowl (儀器) used in ritual ceremonies, and it was fixed in a way so that it could tilt freely. Gong-ja asked the keeper of the shrine, “What is this bowl for?”  And he replied, “It is a bowl you always look at nearby (有坐之器)”  At this, Gong-ja nodded and said, “I did hear about the bowl. It tilts to the side if it’s empty, and it stands upright only if it has just enough water, and if it’s completely filled, it would spill over.”