As early as the Eastern Han Dynasty historian and writer Ban Gu (AD 32-92) divided the ancient and modern figures into "nine scales" in his Han Shugu Ren Jin Table, which was divided into three categories: upper (intelligence), middle (middle) and lower (stupidity). At each level, it is divided into: upper, upper, middle, lower, lower, upper, lower, middle and lower. This may be the source of later classification.

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Many people in our country are deeply influenced by feudal ethics, especially in some family-centered places, so this hierarchical concept is more obvious. So why is this happening! This is about Confucianism in our country. As we all know, our Confucius strongly advocates the Three Cardinal Principles and the Five Permanent Principles, that is, the monarch is the minister's guide, the father is the son's guide and the husband is the woman's guide.

Of course, in some places, people are also forced to respect their elders, so they have to accept the third, sixth and ninth grades. So now we can understand why people are divided into three categories.