Why do you use the image of double carp to refer to letters instead of carp in ancient poetry?

Double carp refers to the ancient people who wrote letters on white silk to avoid damage during transmission. Tied in two pieces of bamboo slips, the slips are carved into fish shapes, hence the name. Later, it became the title of the letter.

The ancient "carp" has another meaning because of the traditional folk auspicious phrase "carp yue longmen".

"yue longmen the Carp" describes the boy in an ordinary family who passed the imperial examination and had a bright future, just like the carp who lived under the water all the year round once jumped out of the water. In ancient times, children always stood in the last line of the family's queue to meet guests, standing in front of the back room, just like carp living underwater, so they were called "children".

The word "Tong" stands from the inside, which means "standing in the innermost part". Therefore, the word "Li" in "Carp" and "Tong" has the same meaning, so the metaphor of "Carp yue longmen" comes into being.

Extended data:

The allusion of double carp comes from the poem "Drinking Horses in the Great Wall Cave" written by Han Yuefu. In ancient times, people often used carp-shaped letters to collect books and letters, so many literati also used carp to refer to letters in their poems. Of course, cooking fish in the poem is not really cooking, but letting their son open a carp-shaped wooden box with a size.

Drinking horses in the Great Wall Cave Han Dynasty: Anonymous

Jiang Chun grass green, endless extension to the distance, makes me miss my husband who travels far away. A husband who is far away from home can not miss him all day, but he can see him in his dream soon. (Yesterday: Yesterday)

I saw him by my side in my dream and woke up to find that he was still in exile. There are different areas in China, and my husband is wandering in China.

Mulberry withered until the wind came, and the sea knew the taste of cold. Fellow travelers home, dear, who will tell me the news of my husband?

A guest came from far away and brought me a carp-shaped wooden box with silk and silk letters in it. Tell the boy to open the wooden box and write a letter with a ruler.

What did you say in your husband's silk letter? The first part of the letter is to increase appetite. It is said that the second half of the letter is often left out.

Explanation:

Looking at the endless green spring grass by the river reminds people of recruiters who travel far away. A husband who is far away from home can't miss him all day, but can only meet him in his dream. I saw him by my side in my dream and woke up to find that he was still in another country. Other towns and villages are different, so I can't see my husband wandering around other places.

Although the dead mulberry has no leaves, it still knows that the wind is blowing, and the sea water is not easy to freeze, but it can also know that the weather is getting cold. Hometown wanderers go home to visit relatives. Honey, who will tell me about my husband? The guests came from far away and gave me a carp-shaped wooden box with silk letters on it. Tell the servant to open the wooden box, which contains a long letter written in plain silk.

Read her husband's letter written in plain silk respectfully. What does it say? The first part of the letter is about increasing your appetite and taking care of your health, while the second part of the letter tells your thoughts.

Baidu encyclopedia-double carp

Baidu Encyclopedia-Carp (CYPRINIDAE)