Why does Liang Wudi want Zhou Xingsi to write thousands of words?

Thousand-character prose is a rhyme composed of 1000 Chinese characters (before Sui and Tang Dynasties, non-rhyming and non-contradictory characters were called "pen" instead of "prose"). During the Southern Dynasties, Liang Wudi (502-549) ordered people to select 1000 non-repetitive Chinese characters from Wang Xizhi's calligraphy works, and asked assistant minister Zhou Xingsi to compile them, which was the first "thousand words" in the history of China. The full text consists of four sentences, which are neat, clear and brilliant, and amazing. Qian Wen Zi is an influential children's enlightenment book in China, with simple sentences and easy memorization.

However, after simplifying Chinese characters and merging variant characters in Chinese mainland, there are only more than 990 different Chinese characters left in the simplified Chinese version (the specific figures vary according to the ownership of variant characters).