We returned home one year from a worldcon (world science fiction convention, for those who may not know the nomenclature)—I forget which year—and promptly I lost a book. Or a box of books. You see, we’d early on gotten into the habit of mailing our purchases home rather than try to take boxes of books on the plane. (The first worldcon we went to in 1984 resulted in about three hefty boxes going back, all of which cost around a hundred and fifty dollars. Today that much would fit in one (small) box.) This system worked pretty well until this time.…