It's probably a collection of extras and the author's thoughts.
The backgrounds of "Can I Stop Reading" and "The Years She Pursued the Medical Saint" are similar. One is focused on the court, and the other is focused on the Jianghu. They are connected in time (not entirely). Some characters will appear in both books, with different degrees of importance, but the plots are almost unrelated.
Chapter 14 and before are all about the contents of the above two ancient books. Chapter 15 will begin with other ancient sayings.
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