I was first exposed to Jorge Luis Borges in college, where I read most of the stories in *Labyrinths *instead of spending time on any of the other classwork I had that quarter. It was the first time I realized you could write fiction about ideas. I was spellbound.

Among my favorite stories was the “The Library of Babel,” which conjures a fictional library that contains every possible permutation of a book that fits certain constraints (each and every book in the library has 410 pages, and each page has a fixed number of characters, including spaces).

Because every possible permutation of the book exists in the library, some magical things result. As is the case when an infinity of monkeys bang away on typewriters for all eternity, most of the books are pure gibberish. But (by definition) there also exist copies of every story ever written in every language in history; and likewise copies of this blog (come to think of it, if I could comb the library easily, it might improve my posting rate).

“The Library of Babel” relies on at least one fancy trick of language — that a finite number of symbols and ideas can be assembled to represent concepts that are infinite (any linguists in the audience care to comment?) It works because the universe Borges crafted is finite, but the atomic units (characters) can be assembled into something that feels infinite.

But why 410 pages and (say) 25 lines per page, and (just guessing here) 80 characters per line?

Why not update the idea in modern terms and reduce the universe to just 140 characters? In other words, what happens if we rethink Borges’ “Library” in terms of tweets?

Well, here’s what we can say more or less definitively:

- Twitter is pretty serious about the 140 character limit. So we have to stick with that.
- We have a limited number of “choices” as to what character can be put into each available slot in the tweet, but its a little hard to figure out exactly how many choices we have. Twitter says that it counts characters based after a tweet has been normalized to something called normalization form c. That’s all fine and well, but what does it really mean? Well, it looks like there are 109,975 graphics characters defined in unicode, which is a lot.
- The total possible number of tweets is therefore 140^109975 (easiest way to think about this is that there are 109,975 possibilities for the first slot and 109,975 for the second slot, which means 109,975 * 109,975 possibilities for the first two characters alone; add another character slot and you multiply by 109,975 again; and 109,975 * 109,975 * 109,975 is 109,975^3; that means for 140 characters, we get 109,975^140. More on permutations here)

This turns out to be a very big number — the library of Babel, Twitter style, has 6.042X10^705 possible tweets. For those keeping track, that’s a number that is a little more than a 6 followed by 705 zeros.

When you compare it to the number of tweets that have happened so far (a little more than 29 billion as of today, per Gigatweet’s counter) its clear we’ve got a ways to go.

But just how far do we have to go?

Well, if we exclude the fact that a lot of tweets are retweets, we discover something discouraging. 29 billion tweets can be written as 2.9×10^10. That’s a drop in the bucket compared to 10^705. Actually, its much less than a drop in the bucket — there is no bucket large enough nor drop small enough that would make the metaphor fit. Even the difference between the smallest theoretical distance (the Planck length, or 1×10^-35 meters) and the estimated diameter of the universe (8.8×10^26 meters) is a mere 61 orders of magnitude, whereas the difference between tweets to date and the number of tweets we’d need for all possible tweets to be . . . er . . . tweeted is 695 orders of magnitude.

So I’m afraid that the only way that we can hope for a Twitter library of Babel is for the rate of tweets to continue to rise exponentially — maybe someone wants to take a crack at figuring out how long it would take if the tweet rate continued to grow exponentially? In the meantime, keep tweeting . . .

I do not know which of us has written this tweet.