Multiples
"By the time this present group of stories was written I had passed through the cultural turbulence that engulfed nearly everyone s life in the wild, stormy period we know as 'the Sixties,' which for me had actually lasted from 1968 to 1974 or 1975. I had come through my own angry four-year-long retirement from writing in the middle 1970s, and was working again at a steady pace, though not with the frenetic prolificacy of the pre-retirement years. At the beginning of this period my personal life was still pretty chaotic, a carryover from all that Sixties madness, and plenty of new chaos was going to descend on me while some of these stories were written, but I was tiptoeing toward an escape from the various messes that were complicating my life, and by the time the last five stories of this volume were being written I was heading into the stability of my second marriage."
Robert Silverberg, from his Introduction