"Thirty years in Hedong, thirty years in Hexi" is a folk proverb, which originated from the natural phenomenon that the Yellow River often changed its course in history. In the past, the Yellow River was not fixed. It often changed its direction (it happened countless times in history). A place used to be on the east side of the river, but in a few years, due to the diversion of the Yellow River, this place will become on the west side of the river. This sentence is a metaphor for the rise and fall of personnel, which is changeable, sometimes changing in the opposite direction and unpredictable.
Related historical allusions:
Guo Ziyi's grandson had to beg after losing all his property. Once, he begged to visit his wet nurse in Hexi Zhuang. I asked a lot of people and said I didn't know. It was getting dark when a farmer came. When he asked, he found that the farmer was the son of his wet nurse. When he went to other people's homes, he saw grain shops and cattle and horses.
He asked the farmer, "Your family is so rich, why do you have to work by yourself?" The wet nurse's son said, "No matter how big the property is, it will be empty. When my mother was alive, she led us to start a business, and this family business came into being. It's fun to be diligent and keep a house! " Guo Sun felt ashamed after hearing this. The master didn't forget his past feelings, so he asked Guo Sun to take care of the accounts at home, but he knew nothing about accounting. The master could not help but sigh: "Indeed, in the past 30 years, Hedong has enjoyed endless prosperity, and in the past 40 years, Hexi has been attached to others."