Of course, we all know that rulers usually block books and public opinions that are different from their own political views. In fact, this situation is very common and normal. There is no doubt that rulers want to consolidate their rule. For example, Qin Shihuang burned books for this reason. Yongle Grand Ceremony, as the netizens said above, once banned many books. The most obvious is "Siku Quanshu". It's all written in middle school textbooks. Qianlong sent ministers to edit Sikuquanshu. He once looked for the reference of Yongle Dadian, but finally found a few, so he went to the folk to find books to copy. Meanwhile, isn't the literary inquisition in Daxing? Then you can find an excuse to ban books. If it doesn't meet the taste of the Qing Dynasty, you can ban books with the year number of the Ming Dynasty. Later, Sikuquanshu became the largest series in China, but its disadvantage was that many books were destroyed and changed, which made the ancient books or modern books we saw distorted and lost their original appearance.
We all know that the first eighty chapters of A Dream of Red Mansions in the four classical novels were written by Cao Xueqin and the last forty chapters were written by Gao E. However, the manuscript of Red is a manuscript. Some people borrow manuscripts from bibliophiles, some copy them, and some just don't return them. In the process of copying, mistakes appeared again. This is how the well-known interchangeable words are produced, which leads to the mistakes and losses of books.
As a result, China's ancient works were destroyed in the Ming and Qing Dynasties, so that some of his current works were not original works at that time. This phenomenon is normal, which is not only caused by poor preservation of book collectors, but also caused by readers' weak awareness of protecting books.