spa fon

"Spa fon" originated as the exclamation of a space alien visitor to a fragment of what was once Earth, in "The Aliens" by Al Williamson in the comic book Weird Fantasy #17 (1952) The aliens find a comic book on one of the Earth remnant fragments. It tells the story of how humans destroyed their whole planet. The final panels of the comic book show the same alien visitors landing on the same planet fragment and then looking at themselves in a depiction of a comic book within the comic book and so on into an infinite regress. The aliens exclaim in amazement, "Spa fon!" "Squa tront!" These became popular catchphrases in science fiction fandom.

We're in an infinite regress! Spa fon!