My favorite
Piers Anthony short story (and one of his first two to be published, thus falling in the better part of his career), the title “
Possible To
Rue” references the
old-timey practice of titling volumes of multivolume reference works by their first and last words.
In the story, a rich man promises his six-year-old whatever (it's a
boy, not a
whatever, but whatever) whatever the child desires as a
birthday present. But when the kid wants a
pegasus, the father feels obliged to demonstrate, by reference to an
encyclopedia, that the creature is mythical, and so cannot be had. The father then cycles through various other animals, demonstrating that
unicorns were equally false, but becoming surprised to see that the encyclopedia similarly describes the
zebra as a creature of myth. The father, increasingly confused, turns to several other animals, confirming in turn that (again, per his encyclopedia) the
mule and even the
horse only exist in the imagination -- the latter despite the father's own memory of having gambled on horses.
As the story progresses, the suggestion being raised is that the father's reticence to buy an exotic animal for his child is itself the motive force behind their disappearance from reality. It ends with the boy asking about the
roc, with the father dutifully looking in the title-drop volume which would contain that
creature.
The story flows crisply and somewhat wittily, enough to combine with the novel premise to make it utterly memorable. Anthony saw the publication of the story in 1963, a time that was just at the beginning of the era of the human
environmental concern that man might extinguish
animal life. The same year he published another short story, "Quinquepedalian," wherein explorers discover a massive and intelligent five-legged life form, itself a metaphor for the human tendency to underestimate the capacity for thought in things different from themselves. Both were later republished in Anthony's 1986 short story collection,
Anthonology, which was where I discovered them, many years ago.