In Tlön, Uqbar, Orbis Tertius, Borges discovered an important clue to toe secrets of Tlön when he found a letter hidden in a book:

In March of 1941, a handwritten letter from Gunnar Erfjord was discovered in a book by Hinton that had belonged to Herbert Ashe.

Gunnar Erfjord and Herber Ashe are both fictional characters who are members of the Orbis Tertius secret society, but who is Hinton? Hinton is mentioned only once in the entire story, so he must be a historical figure. But which Hiton is so famous that he could be referred to just by the last name?

Interestingly, it is the mathematician Charles Howard Hintin, whose fictional and non-fictional writings had inspired the public’s interest in the fourth dimension. He was name-checked in two other stories by Borges (The Secret Miracle and There Are More Things), and was mentioned by H.P. Lovecraft and Aleister Crowley.