ChengYu: 二分明月 Meaning

Traditional: 二分明月

Simplified: 二分明月

Pinyin: èr fēn míng yuè

The idiom, 二分明月, combines the meaning of “flourishing” and “bustling” into one, essentially describing places like New York, Los Angeles, Beijing, and Shanghai, all of which are incredibly prosperous cities.

二分: second part; two parts of (a number)

明月: bright moon

二分明月 has its origins in a poem by 杜牧 (dù mù): 天下三分明月夜， 二分明月在扬州 (tiān xià sān fēn míng yuè yè, èr fēn míng yuè zài yáng zhōu). Translated, the verse means “the world is split up into three and of those three parts; two are in 扬州 (yáng zhōu).”

Throughout Chinese history, the city of Yangzhou has been a symbol of prosperity. Present-day Yangzhou spans much more land than its present location in Jiangsu (江苏；jiāng sū), and because the city was and is near the Yangtze River, trade flourished and continues to flourish in Yangzhou.

The origins of this city start in myth. 大禹 (dà yǔ), a mythical leader made water and started Chinese civilization. As he was making water, DaYu began to split China up into nine sections (九州; jiǔ zhōu), and one of those sections was named Yangzhou. The name Yangzhou referred to the section of Chinese land below the Yangtze River, termed 江南 (jiāng nán). Throughout various time periods and dynasties in Chinese history, Yangzhou encompassed present-day provinces including, 江苏 (jiāng sū), 安徽 (ān huī), 江西 (jiāng xī), 浙江 (zhè jiāng), and 福建 (fú jiàn.)

Because of Yangzhou’s proximity to the Yangtze River, trade was always successful. As such, the living standards of people in Yangzhou were much higher than those living further inland because of the amount of money going in and out of Yangzhou. The idiom 二分明月 specifically describes this prosperity.
Later on, people expanded the restrictions of the idiom to describe any prosperous city.