“Most of the literary works with which we are acquainted fall into one of two classes, those we have no desire to read a second time—sometimes, we were never able to finish them—and those we are always happy to reread. There are a few, however, which belong to a third class; we do not feel like reading one of them very often but, when we are in the appropriate mood, it is the only work we feel like reading. Nothing else, however good or great, will do instead.”
W.H. Auden, “Don Juan” (courtesy of Anecdotal Evidence)