2. Source: This sentence was said by Confucius, and the original text is:

Confucius said, "After my death, the heavier my career, the worse my manners." Zeng Zi said, "What is it?" Confucius said, "Business is good for virtue, and giving is good for non-self. I don't know if a son looks after his father, a man looks at his friends, a gentleman looks at actions, and the land looks at vegetation. Therefore, some people say that living in kindness is like walking into Lan Zhi's room. If you don't smell it for a long time, you will melt with it. If you don't live well, if you enter the place of abalone, you won't smell it for a long time, and you will blend in with it. " Dan hides red and paint hides black. A gentleman must be careful where he is. "

This passage is a dialogue between Confucius and his disciple Ceng Zi. It warns people to choose friends and environment carefully and make friends carefully. In the article, "Living with goodwill is like entering Lan Zhi's room. If you don't smell its fragrance for a long time, you will blend with it. " Being with people who are not easy to get along with, such as entering abalone's place, is like not smelling it for a long time. Being with people of noble character forever is like being bathed in a room full of fragrance when planting Lan Zhi. After a long time, I can't smell the fragrance, but it is full of fragrance; Being with people with bad conduct is like going to a place selling salted fish, and it won't stink after a long time, which has become a famous sentence throughout the ages. In addition, "Dan is red when it is hidden, and lacquer is black when it is hidden" is also extended to the idiom "black when it is near ink".