L. Sprague de Camp and Fletcher Pratt’s The Mathematics of Magic has adventurer Harold Shea discovering a way to travel to the realms of fantasy using math. Following that, we argue about the difference between fantasy and science fiction.
Links:
The Mathematics of Magic by L. Sprague de Camp and Fletcher Pratt [Unknown August 1940]:
https://archive.org/details/Unknown_v03n06_1940-08_unz.org/
John Thomas’s Cube [The Armchair Science Reader, 1959 p.78]:
https://archive.org/details/armchairsciencer0000unse/mode/1up
