The idea of the library as theatrical set, where the content of books is secondary to the atmosphere books create, may gain more respect in coming years. This past May marked the centennial of the New York Public Library’s main branch building. The library is celebrating with a yearlong series of programs and exhibitions focusing on the library’s past as well as its next hundred years. These celebrations, launched with a “Find the Future” festival weekend in May, promote the idea of the library as a stage: an environment where things can happen and people can meet, and one that will retain