"Stealing books" definitely means stealing books. In modern Chinese, "stealing" means stealing. Kong Yiji said this sentence in order to find that meaningless excuse for himself. Although Lu Xun didn't explicitly say that he was stealing books, he told it in a sarcastic way, and the phrase "stealing books is not stealing books" also enriched the image of Kong Yiji.

In fact, when Lu Xun wrote this description of Kong Yiji, the so-called book stealing had a certain realistic basis. This happened in the Shi Jing Library at that time. There is a song blackboard book hidden in the library. This Song blackboard book is very precious, so the library stipulates that this book cannot be checked out. At that time, a master with certain academic attainments wanted to proofread books, so the library set aside a room for him to proofread books.

Then the library sent a librarian to find the master and help him get some books. This task fell to Lu Xun. Later, in a collection of books, the master packed the books and waited for Lu Xun to take them back. As soon as Lu Xun passed, the host was anxious to take his entourage away. Lu Xun felt that something was wrong, and immediately checked it. The Song blackboard book was still there, but it was really gone. At this time, the master noticed that something was wrong and scolded his followers for not putting the books away. Then the entourage looked for his carry-on bag, and Song's blackboard writing was in it.

Because of such a thing, Lu Xun thinks that the master stole the book, which he thinks is an insult. Later, he changed the story a little and added it to Kong Yiji, to some extent to satirize the master. So I think that in Lu Xun's view, stealing books is actually stealing books, which is how he expressed it in Kong Yiji. I personally think that stealing books is stealing books, and the identity of a literate person cannot be a shield for stealing books.