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John Baez (Aug 26 2025 at 16:42):What is more widely used: "sub-double category" or "double subcategory"?
(Both seem horrible to me, so I just want to go with what people most often use.)
Mike Shulman (Aug 26 2025 at 16:44):I would use the former.
Kevin Carlson (Aug 26 2025 at 16:45):By Google results it looks like the latter is about 30 times more common.
Mike Shulman (Aug 26 2025 at 16:46):Ugh.
Mike Shulman (Aug 26 2025 at 16:47):How exactly are you running that comparison? I see plenty of both.
Kevin Carlson (Aug 26 2025 at 16:48):Google counts 5740 results for "double subcategory" and "sub-double category" has only 204, when I search.
Morgan Rogers (he/him) (Aug 26 2025 at 16:52):I find both pleasing to say out loud, but agree with Mike about the more appropriate choice.
Mike Shulman (Aug 26 2025 at 17:18):Okay, I had to look up how to get Google to tell me the total number of hits. However, I'm skeptical that those are meaningful numbers. The very first hit for "double subcategory" is irrelevant. The rest of its first two pages of results are mathematical, but on the third page we have a page that lists a database schema including price:double subcategory:string, the fifth page contains only two mathematical ones, and the sixth page ends with a bunch in Chinese.
Mike Shulman (Aug 26 2025 at 17:20):By contrast, I didn't see any nonmathematical results in the first 7 pages of hits for "sub-double category".
Nathanael Arkor (Aug 26 2025 at 17:22):For comparison, nobody says "2-subcategory" or "multisubcategory", so I don't think there's any good reason to use "double subcategory".
Kevin Carlson (Aug 26 2025 at 17:29):Yeah, those seem like fair arguments, it make sense that it’s easier to get a collision on double subcategory.
Mike Shulman (Aug 26 2025 at 17:32):FWIW I would actually probably say "sub double category" or "sub-double-category", not "sub-double category", since the latter looks to me like "(sub-double) category" rather than the desired "sub-(double category)".
John Baez (Aug 26 2025 at 18:02):Okay, I'll either use "sub double category" or "sub-double-category" or "sub-(double category)"... and probably not the last one, since it's typographically ghastly.
I certainly don't want to convey the impression that it's a "sub-double category", whatever that means.
One-and-a-hafle categories? :face_with_spiral_eyes: Well, we already have sesquicategories.
Mike Shulman (Aug 26 2025 at 18:13):I didn't mean to imply that "(sub-double) category" means anything.
John Baez (Aug 26 2025 at 18:26):I didn't think you had. I was just talking through the evil thoughts that naturally come to my mind whenever I see "sub-double category".
Jonas Frey (Aug 26 2025 at 18:38):I don't know if anybody takes that seriously, but according to the Chicago Manual of Style:
En dashes are also used to connect a prefix to a proper open compound: for example, pre–World War II. In that example, “pre” is connected to the open compound “World War II” and therefore has to do a little extra work (to bridge the space between the two words it modifies—space that cannot be besmirched by hyphens because “World War II” is a proper noun).
Jonas Frey (Aug 26 2025 at 18:39):So it should be sub-category, but sub–double category. Note the subtle difference in length of the lines!
(but maybe the rule doesn't apply since double category isn't a proper noun and thus the space is besmirchable)
Mike Shulman (Aug 26 2025 at 18:48):That's interesting, thanks. I have on occasion written something like "sub–double-category", reasoning that the shorter hyphen would bind tighter than the longer en-dash. But it never occurred to me that a space could bind tighter than any kind of dash.
John Baez (Aug 26 2025 at 18:49):Besmirchable, eh?
I care about the correct use of emdashes and endashes, as in the Birch–Swinnerton-Dyer conjecture, so this is very interesting. But I sure hope nobody ever talks about both sub-double categories and sub–double categories in the same paper. :upside_down:
Mike Shulman (Aug 26 2025 at 18:51):Jonas Frey said:
space that cannot be besmirched by hyphens because “World War II” is a proper noun).
I have no idea what "besmirched" means in that phrase, or what being a proper noun has to do with it.
Mike Shulman (Aug 26 2025 at 19:09):Jonas Frey said:
So it should be sub-category, but sub–double category.
Of course, actually it's just "subcategory".
Kevin Carlson (Aug 26 2025 at 20:15):Mike Shulman said:
Jonas Frey said:
space that cannot be besmirched by hyphens because “World War II” is a proper noun).
I have no idea what "besmirched" means in that phrase, or what being a proper noun has to do with it.
I took it that sticking a hyphen in the middle of a proper noun appearing as a phrase would besmirch its honor, or some such tongue-in-cheek sense that one shouldn't interrupt such an apparent phrase.
Mike Shulman (Aug 26 2025 at 20:22):I guess that makes sense. But would that mean that for an improper noun like "double category" we should besmirch the spaces and write perhaps "sub-double-category"?
Nathanael Arkor (Aug 26 2025 at 21:17):John Baez said:
I certainly don't want to convey the impression that it's a "sub-double category", whatever that means.
(I personally think "sub-double category" reads fine.)
Nathanael Arkor (Aug 26 2025 at 21:24):Jonas Frey said:
I don't know if anybody takes that seriously, but according to the Chicago Manual of Style:
I wonder whether this is a convention in British English too... From a cursory search, I only saw American English style guides recommending it.