What's the point of writing outside the fence?

Since ancient times, perhaps it is a primitive impulse.

In ancient times, many literati liked to write poems on houses, halls, pavilions, buildings, temples, temples, delivered walls, rock walls and other walls. To show their skills and abilities. Cui Hao's Yellow Crane Tower is inscribed on the pink wall of the Yellow Crane Tower, Li Shangyin's Monk Wall is inscribed on the wall of the temple, and Lu You's Restaurant Wall is inscribed on the wall of the hotel. In addition to the joy of literati, they also want to exchange their poems for drinks, which is equivalent to advertising temples or restaurants and attracting customers. Of course, most poems or articles carved on the wall are very short. After all, the wall is limited, so make it bigger so that some people can't see it. There are also some good people who write a lot of pornographic words on the wall, either writing about the charm of beautiful women or directly going down the road, and some yellow jokes make people laugh. However, some literati disdain to look at these things, and they also disdain to let their poems interact with these things.

The custom of writing on the wall has existed since ancient times. Maybe people see a bare wall and think it is ruined without some words or pictures. Therefore, they will write poems and draw pictures on it, not only to make themselves famous, but also to make the position of the wall famous. And unknown people also want to be famous, but their talents are not enough, so they have to write some limerick or draw a few strokes casually, which is considered graffiti. Some people pretend to be celebrities and write poems on the wall, so that future generations will spread the truth without distinguishing between true and false.

This custom of writing on the wall seems to come from the closing ceremony of the emperor. The emperor is going to Mount Tai to hold a ceremony to close the Zen Buddhism. He wants to remember his achievements and carve words on stones for long-term spread. And the military commander won the battle, he will also remember the merits. Scholars don't have the financial resources to remember their achievements, and they don't carry hammers and chisels with them, only pen and ink, so they can only write poems on the wall, or write them on paper and stick them on the wall. If they want to remember their own achievements, they are likely to be misunderstood by the emperor and commit rebellion. Therefore, literate scholars write on the wall, and people with low educational level should follow suit and write on the wall, resulting in a large number of wall literature and even toilet literature.