“‘—All You Zombies—’” (1959)
Robert A. Heinlein (writer).
The very finest solipsist SF, cleaning up “By His Bootstraps” (1941). Granted, the perspective on gender transitions is clearly dated and Heinlein has too much fun with the idea of the “WENCHES” in this story written for Playboy, but the details are rendered incidental by the thought experiment, culminating in the protagonist lying awake, gripped by the sort of high-power speculation that prompted the author. I wonder whether the sexist joke was influenced by reading the British WW2 “Women’s Auxiliary Air Force” (WAAF) acronymically, as “waif” or “wife”. I also wonder whether some looped structuralist ontology brought Playboy into existence just to carry this one story.