> This is true for Hindi and Urdu, esp when you're exposed to both. When you study both the languages theologically and linguistically, the differences become ever more apparent. It is only the mash of Hindi-Urdu called Hindustani [1] (popularized in modern day by Bollywood) that's mutually intelligible to both Hindi and Urdu speakers alike, and only in its spoken form.
You make it sound like everyday Hindi and everyday Urdu are far apart, but I'm not sure if that's true: if you took a Pakistani Urdu speaker and an Indian Hindi speaker, both from the middle class with only a modest amount of education (and therefore limited access to specialized technical vocabulary), both would have no trouble at all talking to each other. Occasionally one might use a word where the other might have preferred a different one (like زبان for the Urdu speaker and भाषा for the Hindi speaker for 'language'), but it's only possible to imagine them struggling if both were attempting to speak in the registers that are only used in exceedingly formal, technical, or literary contexts.
And when you ignore vocabulary, it becomes even more clear: the grammar of even highly Sanskritized Hindi is more or less identical to that of everyday Hindi, and while I'm less sure about what high Urdu is like, I don't think it differs grammatically from everyday Urdu either, with the possible exception of ezafe[1] (which both Hindi and Urdu speakers are perfectly able to comprehend, even if they do not produce it).
edit: this is Colin Masica's take in his book The Indo-Aryan Languages (p.27):
> The ultimate anomaly in the what-is-a-language dilemma in Indo-Aryan is presented by the Hindi-Urdu situation. Counted as different languages in sociocultural Sense B (and officially), Urdu and Modern Standard Hindi are not even different dialects or subdialects in linguistic Sense A. They are different literary styles based on the same linguistically defined subdialect.
> At the colloquial level, and in terms of grammar and core vocabulary, they are virtually identical; there are minor differences in usage and terminology (and customary pronunciation of certain foreign sounds), but these do not necessarily obtrude to the point where anyone can immediately tell whether it is "Hindi" or "Urdu" that is being spoken. At formal and literary levels, however, vocabulary differences begin to loom much larger (Hindi drawing its higher lexicon from Sanskrit, Urdu from Arabic and Persian), to the point where the two styles/languages become mutually unintelligible. To the ordinary non-linguist who thinks, not unreasonably, that languages consist of words, their status as different languages is then commonsensically obvious, as it is from the fact that they are written in quite different scripts (Hindi in Devanagari and Urdu in a modified Perso-Arabic).
> You make it sound like everyday Hindi and everyday Urdu are far apart, but I'm not sure if that's true: if you took a Pakistani Urdu speaker and an Indian Hindi speaker, both from the middle class with only a modest amount of education (and therefore limited access to specialized vocabulary), both would have no trouble at all talking to each other.
Hence this from the parent post: It is only the mash of Hindi-Urdu called Hindustani (popularized in modern day by Bollywood) that's mutually intelligible to both Hindi and Urdu speakers alike, and only in its spoken form.
> And when you ignore vocabulary...
That's the crux of my point. The punjabi dialects vary mostly in phonetics and not so much in vocabulary. In my case Gujarati and Lisan ud Dawat aren't exactly mutually intelligible in spoken form and most def not in their written form. As for Hindi-Urdu, it is mutually intelligible when in its hugely popular Hindustani [0] form, which is what your saying as well, I think.
> I don't think it differs grammatically from everyday Urdu either, with the possible exception of ezafe.
That's one difference that has Perso-Arabic tilt to it. The Urdu/Rekhta literature has other elements [1] that diverge from high Hindi that it couldn't possibly pass off as the same language as Urdu, imo. Exhibit A: https://www.rekhta.org/ghazals Most native Hindi speakers would have trouble parsing through most of those Urdu ghazals, I'd reckon.
> At formal and literary levels, however, vocabulary differences begin to loom much larger (Hindi drawing its higher lexicon from Sanskrit, Urdu from Arabic and Persian), to the point where the two styles/languages become mutually unintelligible.
Exactly. For a language like Lisan ud-Da'wat spoken by a much less number of people, there's a common ground with Gujarati which is simply to speak the main language Gujarati itself, even if the core vocabulary and grammar are similar between the two. The only thing working for Hindi-Urdu mutual intelligibility, imo, is that Hindi is spoken by a large number of people who are exposed to Urdu, on a day to day basis, and vice versa.
I guess, like someone mentioned [2], 'a language is a dialect with an army and a navy.'
Punjabi dialects do vary in vocabulary. Just go to Indian Punjab, and converse with people from Majha, Malwa, Doaba or Poadh. You will instantly find differences. Singers from Majha sometimes use vocab that needs help translating.
Legal vocabulary in the sense of interacting with the court or revenue system (patwaris, thanedars, kotwals) is still strongly mutually intelligible IIRC
You make it sound like everyday Hindi and everyday Urdu are far apart, but I'm not sure if that's true: if you took a Pakistani Urdu speaker and an Indian Hindi speaker, both from the middle class with only a modest amount of education (and therefore limited access to specialized technical vocabulary), both would have no trouble at all talking to each other. Occasionally one might use a word where the other might have preferred a different one (like زبان for the Urdu speaker and भाषा for the Hindi speaker for 'language'), but it's only possible to imagine them struggling if both were attempting to speak in the registers that are only used in exceedingly formal, technical, or literary contexts.
And when you ignore vocabulary, it becomes even more clear: the grammar of even highly Sanskritized Hindi is more or less identical to that of everyday Hindi, and while I'm less sure about what high Urdu is like, I don't think it differs grammatically from everyday Urdu either, with the possible exception of ezafe[1] (which both Hindi and Urdu speakers are perfectly able to comprehend, even if they do not produce it).
edit: this is Colin Masica's take in his book The Indo-Aryan Languages (p.27):
> The ultimate anomaly in the what-is-a-language dilemma in Indo-Aryan is presented by the Hindi-Urdu situation. Counted as different languages in sociocultural Sense B (and officially), Urdu and Modern Standard Hindi are not even different dialects or subdialects in linguistic Sense A. They are different literary styles based on the same linguistically defined subdialect.
> At the colloquial level, and in terms of grammar and core vocabulary, they are virtually identical; there are minor differences in usage and terminology (and customary pronunciation of certain foreign sounds), but these do not necessarily obtrude to the point where anyone can immediately tell whether it is "Hindi" or "Urdu" that is being spoken. At formal and literary levels, however, vocabulary differences begin to loom much larger (Hindi drawing its higher lexicon from Sanskrit, Urdu from Arabic and Persian), to the point where the two styles/languages become mutually unintelligible. To the ordinary non-linguist who thinks, not unreasonably, that languages consist of words, their status as different languages is then commonsensically obvious, as it is from the fact that they are written in quite different scripts (Hindi in Devanagari and Urdu in a modified Perso-Arabic).
[1]: https://en.wikipedia.org/wiki/Ez%C4%81fe