For these years it has been seen in the library world not only to interpret a library itself but also to find out in the history of libraries a new sphere of the library development.
An opposite remark against two theses of Seiji Yamamoto’s “The energy of the library development, a study of the history of libraries” and Yasuhiko Sugiyama’s “A power of creating a library, a method of the history of libraries” are taken here under the three subjects: a new trial of the theory of the library development, some problems concerning the two theses, and preservation and utilization on the library development.