Gui Zhi, Luoyang: Zuo Si, a writer in Jin Dynasty, was a naughty boy when he was a child, and he didn't like reading. Father often loses his temper, but Xiao Zuosi is still very naughty and refuses to study hard.

One day, Zuo Si's father was chatting with his friends, who envied him for having a clever and lovely son. Zuo Si's father sighed and said, "Stop talking about him. Zuo Si's study in childhood was not as good as that in my childhood. It seems that there is not much promise. " Said, and a look of disappointment appeared on his face. All this was seen and heard by Xiao Zuosi. He is very sad and thinks it is really useless not to study hard. So, I secretly made up my mind that I must study hard.

Day after day, year after year, Zuo Si grew up gradually. Because of his persistent hard work, he finally became a knowledgeable person, and his articles were very good. He spent a year writing Du Fu of Qi, which showed his talent in literature and laid the foundation for him to become an outstanding writer. After that, it is planned to write Sandu Fu with the customs and products of the capitals of Wei, Shu and Wu in the Three Kingdoms as the content. In order to reach a certain level in content, structure and language, he devoted himself to research, carefully wrote and forgot to eat and sleep for ten years, and finally wrote the literary masterpiece Sandu Fu.

Sandu Fu has always been criticized, and people compare it with Sandu Fu, a literary masterpiece of Han Dynasty. Because printing had not been invented at that time, people who loved Sandu Fu had to scramble to copy it. Because there were too many people copying it, the supply of paper in Luoyang, the capital, was in short supply, and the price of paper in the whole city once rose sharply.

This story comes from the biography of Jin Shu Wen Yuan Zuosi. The idiom "Luoyang paper is expensive" is to praise the popularity of excellent works.