Heinlein was writing again by November—a new novel, kicked off by something Ginny had said about “Gulf,” written thirty years earlier: Kettle Belly Baldwin, she said, had been one of his juiciest characters, and he hadn’t done nearly as much with him as he could have. Heinlein seems to have combined that comment with a bit he had mentioned in passing in Time Enough for Love, about assembling people out of genes from many different sources: His protagonist was a composite of the genes of both Gail and Joe Green, who had never had a chance to procreate in “Gulf.” His protagonist for Friday is a genetic composite of the best of humanity, in a balkanized United States, which symbolically reflects Friday’s own genetic balkanization—a true human who is nevertheless a true superhuman and who gains interior unity by the end of the book. Friday naturally led back to the subject of bigotry—and in the era of the Equal Rights Amendment, who better to represent humanity as a whole and the damage done by bigotry—and the possibility of self-healing that had always fascinated him—than a woman, Friday…

…He started writing in November 1980, while Ginny began researching the current generation of computers to replace typewriters and paper files… Heinlein finished Friday in late March—just in time for the April 1981 issue of Omni…

Robert A. Heinlein: In Dialogue with His Century, Volume 2: The Man Who Learned Better (1948-1988) by William H. Patterson