How to interpret the old saying of China, that is, three generations are rich but three generations are poor?

In fact, the ancient people were poor, mostly because their education level was too low. Only a large number of rich people could afford to go to private schools. Rich families invited tutors and extremely young children to accompany their sons and daughters to study. It has caused a large number of people to be illiterate and can only do some simple things. I have no knowledge and mind to think about all kinds of strange things. You can only work for landlords and businessmen, or make a living as a soldier. Furthermore, I reclaimed wasteland and planted it for a living. Life is simple, and there is no upward channel. As a result, the poor are getting poorer and the rich are getting richer. Nowadays, most of the poor people are just born poorly, and they can still live a rich life through their own efforts. Here, Xiaobian introduces a book and introduces the ancient private school culture, which interested readers can read.