I am not a native speaker, so maybe the question is based on biased or plain wrong observations.
However, it seems to me that “long” and “short” cannot be freely substituted in English time expressions.
For example, you can say
I won’t be long
They will come shortly
They are long gone
But you can’t say
I won’t be short
They will come long(ly) (and by the way, why isn’t “longly” a word?)
They are short gone (though you could say "they are gone shortly, but that has a different meaning)
Is this actually true, or am I making it up? If true, is there some underlying antropological/social/linguistic explanation other than “because usage”?
All of the instances you mention as OK are really fossilized usage patterns. If those usages hadn’t already existed, people would likely not say them that way. All of those situations in the second group can be reworded using the same construction:
I won’t be back for a while
It’ll be a while before they’re here.
They’ve not been gone a while
And in turn, those can lead to alternate methods of saying the first set:
I’ll be back in a while
It won’t be a while before they’re here.
They’ve been gone a while.
All of these are longer phrases, and are more likely to be ones that people come up with spontaneously in absence of a set phrase.
It’s somewhat similar how you might describe someone as “nonplussed” or “uncouth” but never “plussed” or “couth”. The nonnegative versions of those adjectives didn’t survive usage shifts, while the negative versions did. So there might have been a time when those second set of sentences might have been said, but they weren’t used as frequently and thus didn’t become a stock phrase, while those used more frequently became stock phrases. When usage shifted so that the second set of sentences wouldn’t be spontaneously created, that didn’t prevent the first set of stock phrases from still being used.
I’m reminded of the fact that in Indian English, there is a word “prepone” that means the opposite of “postpone”. Why it’s used there and generally not understood elsewhere in the English speaking world, I don’t know.
I do notice that, in all these examples, “long” or “shortly” are used as adverbs. As you note, there is no English word “longly.” “Short” can be used as an adverb, but it’s less common.
Are all examples of short/long asymmetry when they’re used as adverbs?
As in many commonly used phrases, they have been shortened:
** I will not be away for a long time. I will be back soon.
** They left a long time ago.
“They will come shortly” is more colloquial and not generally used in English English. We would use “soon”.
English is full of these expressions and they go a long way to make it more expressive and interesting. In written English an author will often look for different ways to express the same idea, to avoid repetition.
Some people do, but it always sounds slightly off to me. I can’t say it’s wrong but it doesn’t sound quite right either. I would say “a short time ago” instead, which according to a Google search is many times more common. On the other hand “shortly before” and “shortly afterward” both sound perfectly normal to me, as do the corresponding “long before” and “long afterward”.
Nonetheless, it’s peculiar how one form would stay in use and the other not, considering how the underlying meanings should be more or less equally frequent in usage. I also wonder if there are some generalizations that can be drawn
This isn’t unique to English. All languages have idioms; ways in which word are used and/or combined that seem natural and appropriate to native speakers, versus ways that do not. “I won’t be long” is idiomatic in most varieties of English; “I won’t be short” is not. Idiom doesn’t have to be coherent or consistent, and frequently isn’t. You can’t say more than that.
This does get some use. I’m not 100% sure if modern use isn’t a resurrection that has arisen partly from the humour of using a somewhat archaic word. But it is certainly a real word that arises from time to time in conversation.
Some of the asymmetry is not specific to time, either. Among the many meanings of “short,” one is “to be lacking something needed.” The opposite of that isn’t long, and that’s fine.
You can be short on time. But you can also be short on gas and therefore have to pull over. Or you can be trying to make pancakes and be short on blueberries. Or you can hope to buy that book ring but discover that you’re short by three bucks.
Having a surplus of these resources is the opposite condition, but “long” has no obligation to be a universal antonym to “short.” It’s the antonym to some of the definitions of “short” (particularly in a distance/length contexts) but not others.
Some people above note how they use “long” as an antonym in at least some of the above contexts, but I would claim that they typically do so while secretly smiling in their mind at the clever turn of phrase and that an average listener will need to take a micropause to catch the meaning and may even crack a smirk themselves. Which is to say, it’s not actually standard and unremarkable usage, but it doesn’t mean you can’t say it.
If it means the opposite of what “uncouth” has come to mean, then that version of “couth” is new. “Couth” originally meant “well-known” and someone who was unknown was more likely to be uncultured, so that’s where “uncouth” drifted.
I disagree, at least as to US English. To be “short of [something]” may mean a total lack but more often means an insufficiency. When you have 1 cup of blueberries but the recipe calls for three you are “short of blueberries”.
“You’re long in/on [whatever]” is the corresponding usage. Meaning you have a surfeit of whatever.
E.g. Our connection is too long on time to just sit at the stupid airport awaiting the next flight but too short to leave and ride the train downtown to get lunch. We’re short of men but long on women for the line dance. etc. For a hundred examples.
In no sense are these nonstandard smirky usages. At least not in the brand of US English I grew up with.
That is the same sense in which I meant it. “Lacking” was perhaps an ambiguous word choice. My blueberries example, for instance, was in the line of “…therefore not everyone gets to have blueberries in their pancakes.”
But – do people really say “Oh, great, we’re long on blueberries, so let’s make pancakes today”? Only to be cute, right, or as part of a microculture’s argot?
For the time case specifically, here’s the distribution of usage of “short/long on time” over time: Google Ngram Viewer
Clicking into the actual hits shows that the majority of the “long on time” cases are actually “long on-time” (so, a false match to this meaning), but there are examples of the target usage mixed in there, usually in a poetic/parallel construction (“He was short on money and long on time” or similar). Which does make it technically “in use”, but still niche enough to argue that there’s a significant asymmetry present.
So many countries and territories have English as their official language, it would be interesting to learn other instances of usage shift from posters living, or who grew up in those places. Perhaps a different thread (started by one of you linguistically knowledgeable folks) would be fun.