How Lewis Carroll computed determinants (2023)
148 points
9 hours ago
| 6 comments
| johndcook.com
| HN
esafak
8 hours ago
[-]
> Arrange the given block, if necessary, so that no ciphers [zeros] occur in its interior.

I forgot that cipher used to have a different meaning: zero, via Arabic. In some languages it means digit.

reply
sundarurfriend
7 minutes ago
[-]
In Tamil, it still means a zero. It's usually pronounced like 'cyber' though, because Tamil doesn't have the 'f'/'ph' sound natively.
reply
pinkmuffinere
8 hours ago
[-]
lol I never made that connection — in Turkish, zero is sıfır, which does sound a lot like cipher. Also, password is şifre, which again sounds similar. Looking online, apparently the path is sifr (Arabic, meaning zero) -> cifre (French, first meaning zero, then any numeral, then coded message) -> şifre (Turkish, code/cipher)
reply
cgio
5 hours ago
[-]
The Turkish password word may be the same used for signature? I suspect so, because in Greek we have the Greek word for signature but also a Turkish loan word τζίφρα (djifra).
reply
esafak
4 hours ago
[-]
imza is signature while şifre is password. I imagine the conflation occurred because signatures are used like passwords for authentication...
reply
NextHendrix
4 hours ago
[-]
Likewise, the monogram of the sitting english monarch (as seen on postboxes and so forth) is the "Royal Cypher".

https://en.wikipedia.org/wiki/Royal_cypher

reply
pinkmuffinere
4 hours ago
[-]
Hmm i don’t think that one is related in Turkish — i only know of “imza” as signature, but there could also be other variants.
reply
celaleddin
7 hours ago
[-]
Nice! Imagine the second meaning going back to Arabic and now it's a full loop! It can even override the original meaning given enough time and popularity (not especially for "zero", but possibly for another full-loop word).
reply
jacquesm
7 hours ago
[-]
Dutch too: "Cijfer", German, "Ziffer", French: "Chifre", Spanish: "Cifra".
reply
estomagordo
6 hours ago
[-]
Swedish: "Siffra"
reply
BobbyTables2
1 hour ago
[-]
Wow, I never realized the cofactor method wasn’t the only one.

I loathed it and it put me off wanting to get into advanced matrix topics.

reply
howling
2 hours ago
[-]
reply
kazinator
7 hours ago
[-]
> Dodgson’s original paper from 1867 is quite readable, surprisingly so given that math notation and terminology changes over time.

Given that Jabberwocky is also quite readable, we shouldn't be too astonished.

reply
01jonny01
5 hours ago
[-]
When I'm not cognitively depleted from over working and kids I'd really like to sit down and read this properly.
reply
messe
9 hours ago
[-]
HN title filter cut off the initial "How".

You can manually edit it back in.

reply
marcusestes
8 hours ago
[-]
“Drop the ‘how.’ It’s cleaner.”
reply
vharuck
8 hours ago
[-]
It gives it a different implication. As I read it, an article titled "Lewis Carroll Computed Determinates" has three possible subjects:

1. Literally, Carroll would do matrix math. I know, like many on HN, that he was a mathematician. So this would be a dull and therefore unlikely subject.

2. Carroll invented determinates. This doesn't really fit the timeline of math history, so I doubt it.

3. Carroll computed determinates, and this was surprising. Maybe because we thought he was a bad mathematician, or the method had recently been invented and we don't know how he learned of it. This is slightly plausible.

4. (The actual subject). Carroll invented a method for computing determinates. A mathematician inventing a math technique makes sense, but the title doesn't. It'd be like saying "Newton and Leibnitz Used Calculus." Really burying the lede.

Of course, this could've been avoided had the article not gone with a click-bait style title. A clearer one might've been "Lewis Carroll's Method for Calculating Determinates Is Probably How You First Learned to Do It." It's long, but I'm not a pithy writer. I'm sure somebody could do better.

reply
miltonlost
7 hours ago
[-]
"How Lewis Carroll Computed Determinates" is fine and not clickbait because it provides all the pertinent information and is an accurate summary of its contents. Clickbait would be "you would never guess how this author/mathematician computed determinants" since it requires a clickthrough to know who the person is. How is perfectly fine IMO to have in the title because I personally would expect the How to be long enough to warrant a necessary clickthrough due to the otherwise required title length.
reply
867-5309
5 hours ago
[-]
it's not quite McKean's Law so I'll settle for contagious
reply