Funes is a most remarkable man, superhuman in some respects, proto-human in others. He has perfect memory and remembers every sensation he has ever experienced but these hyper-detailed recollections torment him and he suffers from chronic insomnia. To mitigate his insomnia he sets himself nocturnal projects, one of which involves giving every (whole) number a unique name. "...in a very few days he had gone beyond twenty-four thousand". This is a completely crazy project, of course, "precisely the contrary of a system of enumeration" and requiring an infinite length of time for its completion. It makes a charming footnote, completely optional as such footnotes are, to the introduction of the natural numbers.
Consistent with his perfect recollection of every experience, Funes is almost incapable of abstraction. He would struggle to understand why the word, "dog" could apply to both a Scots terrier and an Irish wolfhound. If each object we meet in the world is unprecedented, why would we even need numbers at all? They could become a game of the sort that Funes plays.
It's typical of Borges that a story of just a few pages should contain such rich, deep ideas. The story was first included in the collection, Ficciones, translated in English as Fictions, and can be found in other collections. I think the first translation of Fictions was published in 1962, so these stories are probably still copyrighted. I will leave it to you and Google if you want to try to find a free copy online.
Last Thursday, discussing functions, I wanted to underline the idea of "dummy variable", that we use a letter like f to stand for a function, not its value or its operation, and that once we have temporarily introduced a symbol, e.g. x to stand for "the number we are going to give to f", we don't really care about x again after that; x is just a placeholder and we discard it once it's done its job, of explaining how the function works. So we can write, e.g.
f(x) = 2x-1
but then ask, what is the value of f(2), f(-14.7), f(a), f(p2), etc. We can even suppose that a more modern Ireneo Funes has chosen to call one number, Bobdylan and write
f(Bobdylan) = 2*Bobdylan-1
We supposed that Bobdylan was Funes' name for 17. Then the result of this operation would be 33. From the class came the suggestion that Funes would have named 33, Batman. So we were able to write,
f(Bobdylan) = Batman
Of course there was a reaction: "Please leave that on the board for the next class."
