In the pre-Qin period, surnames were separated. Don't marry by surname, and don't rank by surname. Surnames are also the product of feudal system and patriarchal system. The emperor gave fiefs to princes, who took the name of fiefs as their surnames.

Wang's eldest son can inherit his father's surname, while illegitimate children can only take Shiyi or grandfather's official position, posthumous title and font size as their surname. After Qin unified the six countries, surnames became one, and surnames were basically replaced by surnames.

The dispute over the ancestor of Miao surname;

The debates on Miao surname in Song Jinshi, Miao Yu surname in Song Jinshi and Miao surname in Qing Dynasty all indicate that Donghai County, Lanling County and Langya County are all in Lu, so-called "three places to see", and Qin is far away from Lu, so it is inferred that Miao's ancestor came from Lumugong, and his surname is Ji, which is famous all over the world.

Gulanling County originally belonged to Donghai County and was the seat of Tan State. Tan belonged to Lu in a short time, and was occupied by Wu, Yue and Chu after 487 BC.

It shows that before Lu Mugong was born, Lanling had nothing to do with Lu. In addition, Langya County has always been in the ancient times of Qi. 1972 in the silk book "Muhe" unearthed in Mawangdui, Changsha, there is a figure Muhe, who is a student of Confucius. According to Confucius' age, Muhe is older than Lumugong 100 years old and about 50 years younger than Qin Mugong.

Thirdly, we can see that Lu Ji's viewpoint is quite different from the actual situation. According to the principle of patriarchal clan system in Zhou Dynasty, the possibility that Miao ancestors respected posthumous title Lumugong as their surname is controversial.