If we only look at the value of cultural relics, the paper version of ancient literature is indeed not suitable to be opened to readers on a large scale, otherwise, frequent reading and the resulting bacterial invasion will certainly affect their preservation to a great extent. However, from the perspective of the value of historical materials, it should have been open to the society, because only in this way can the literature value of ancient books be fully realized and great progress can be made in academic research.
 The passage that focuses on the description of ancient literature is 'Whether it is open or not is a difficult problem.'