What are the reasons why ancient books in Song and Yuan Dynasties are valued and sought after by the world? Expect a profound and organized view.

The answer upstairs is relatively simple, but it is also correct. Hehe, although paper books began to appear in the Tang Dynasty before the Song Dynasty, most of them were Buddhist books. It was not until the invention of printing in Song Dynasty accelerated the birth of books that later generations had the cultural heritage of butterfly clothes. On the one hand, the literary works recorded in books are closer to the original documents (that is, closer to the newly generated documents) and are not prone to errors and omissions. Moreover, the Song Dynasty was the peak of the development of literature and culture, and scholars came forth in large numbers. With the changes, many literary works that can be seen everywhere have become trivial for various reasons and can only be seen occasionally in excerpts from other books. As a result, later generations began to collect previous editions, proofread them, and upgrade and expand out-of-print literary books. In this process, people discovered the advantages of Song edition books through constant proofreading, and slowly began to pay attention to Song edition. By the Yuan and Ming Dynasties, the awareness of books in the Song Dynasty had been quite precious, and there was a saying that "one page in the Song Dynasty was worth one or two ounces of gold". In modern times, compared with the Song version, some contents can be said to have completely changed into two meanings. Therefore, books in Song Dynasty became the first choice for literati to pursue collection. With the recovery of the modern economy and the recovery of the collection market, people's first choice for the market of ancient books collection will of course be the Song edition: first, because the literati in the past dynasties attached importance to the Song edition and praised the Song edition books in the long river of history, and second, because of the age change of the Song edition books in books, it has become a rare collection, even if there are books at home, it is hidden. After all, the world of collection is rare! The above is my personal understanding, I hope it will help you!