ऐ दर्या-ए क़ैद् दर् सीनः-ए मन् ... (اَے دَرْیَا ئ قَیدْ دَرْ سِینۂ مَنْ ۔۔۔): The Hindi-Urdu Dichotomy

The Hindi-Urdu Question

Urdu and Hindi are generally held to be two distinct languages in popular opinion. And, indeed, viewed through the narrow sociolinguistic lens, there is no arguing that these are two distinct languages. However, what about linguists at large? Do they agree?

Much work on addressing this issue has already been done. So, instead of re-inventing the wheel, allow me to simply borrow from existing work and synthesize it in this post. This post remains a work-in-progress and will continue to be updated and augmented as and when I get the opportunity to do so.

Terminology adopted for this post

Hindi: A specific standard register based off the Khari Boli (खड़ी बोली) dialect of the Dehli region. It is now the National Language of India.

Urdu: A specific standard register based off the Khari Boli (खड़ी बोली) dialect of the Dehli region. It is now the National Language of Pakistan, and also accorded the status of an official language in the Constitution of India.

Hindvi: An umbrella term that not only encompasses the varieties of Khari Boli tongues but also non-Khari Boli tongues in the North Indian subcontinent. (Sometimes, the word Hindustani is used for this purpose, and more commonly the umbrella term Hindi is used which can lead to confusion if the distinction is not clear.)

Two Languages or Two Dialects?

The Wikipedia entries which already condense the research and opinions in one place are a good starting point. The introductory section of the Wikipedia page for Urdu states the following (extract 17-Jul-2010, emphasis mine):

Urdu is often contrasted with Hindi, another standardised form of Hindustani. The main differences between the two are that Standard Urdu is conventionally written in Nastaliq calligraphy style of the Perso-Arabic script and draws vocabulary more heavily from Persian and Arabic, while Standard Hindi is conventionally written in Devanāgarī and draws vocabulary from Sanskrit comparatively more heavily. Most linguists nonetheless consider Urdu and Hindi to be two standardized forms of the same language [20]; others classify them separately [21], while some consider any differences to be sociolinguistic [22].
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[20] "Hindi, Hindustani, Urdu could be considered co-dialects, but have important sociolinguistic differences.", Ethnologue Report for Hindi.
[21] Ralph Russell, “Some notes on Hindi and Urdu", The Annual of Urdu Studies, vol. 11, 1996, pg. 204.
[22] Asghar Ali Engineer, "Urdu and its Contribution to Secular Values", May 1998.

I personally lean towards the first and the third options. I agree that at the sociolinguistic level the two languages can easily be argued to be distinct. However, I join the linguists who hold that they are two standard forms of the same Khari Boli (खड़ी बोली) dialect within the Hindvi dialect soup. Effectively, that makes them sister dialects in the Hindvi family of tongues.

The Wikipedia entry for Hindi has a full section devoted to a more formal appreciation of the differences. The paragraphs of interest are (extract 17-Jul-2010, emphasis mine):

Standard Hindi and Urdu are understood from a linguistic perspective to indicate two or more specific dialects in a continuum of dialects that make up the Hindustani language (also known as "Hindi-Urdu"). The terms "Hindi" and "Urdu" themselves can be used with multiple meanings, but when referring to standardized dialects of Hindustani, they are the two points in a pluricentric language.
...
Linguistically, there is no dispute that Hindi and Urdu are dialects of a single language, Hindustani/Hindi-Urdu. However, from a political perspective, there are pressures to classify them as separate languages. Those advocating this view point to the main differences between standard Urdu and standard Hindi:
the source of borrowed vocabulary;
the script used to write them (for Urdu, an adaptation of the Perso-Arabic script written in Nasta'liq style; for Hindi, an adaptation of the Devanagari script);
Urdu's use of five consonants borrowed from Persian script.
Such distinctions, however, are insufficient to classify Hindi and Urdu as separate languages from a linguistic perspective.
...
The rubric "Hindi" is often used as a catch-all for those idioms in the North Indian dialect continuum that are not recognised as languages separate from the language of the Delhi region. Bihari and Chhattisgarhi for example, while sometimes recognised as being distinct languages, are often considered dialects of Hindi. Many other local idioms, such as the Bhili languages, which do not have a distinct identity defined by an established literary tradition, are almost always considered dialects of Hindi. In other words, the boundaries of "Hindi" have little to do with mutual intelligibility, and instead depend on social perceptions of what constitutes a language.

The other use of the word "Hindi" is in reference to Standard Hindi, the Khari Boli register of the Delhi dialect of Hindi (generally called Hindustani) with its direct loanwords from Sanskrit. Standard Urdu is also a standardized form of Hindustani. Such a state of affairs, with two standardized forms of what is essentially one language, is known as a pluricentric language.

The above extracts outline the nominal linguistic opinion on this 'false' dichotomy between Hindi and Urdu; i.e. the linguistic consensus is that they are both dialects in a 'clinal continuum'.

But don't different scripts mean different languages?

The relationship between a language and a script is many-to-many (M:N). In other words, a single language could adopt multiple scripts (e.g. Konkani is written in Roman, Kannada, Devanagari scripts depending on the where the speaker is located), or a single script may be used by multiple languages (e.g. Devanagari is used by both Marathi and Hindi). Further, many languages do not have any form of writing at all. As a result, a script does not form a basis for distinguishing between dialects and languages.

Also, consider that writing, and thus scripts, are relatively modern inventions compared to language. If scripts were the primary way to distinguish between languages, then for the era prior to the invention of scripts one would be hard-pressed to argue about language and dialect variation.

Finally, the script question is a non-issue linguistically because linguistic analysis relies on phonology, morphology, syntax, pragmatics, and semantics.

A Comparative Grammar

A good starting resource on comparative studies of modern Indic languages is the three volume book "A Comparative Grammar of the Modern Aryan Languages of India" by John Beames. I reproduce below some of the relevant extracts from that book. Some of the contextual information is dated, though the linguistic aspects pertaining to Hindi/Urdu are not. (Again, all emphasis mine.)

{pp. 31-32}: Under the general head of Hindi are included many dialects, some of which differ widely from one another, though not so much so as to give them the right to be considered separate languages. Throughout the whole of this vast region, though the dialects diverge considerably, one common universal form of speech is recognized, and all educated persons use it. This common dialect had its origin apparently in the country around Delhi, the ancient capital, and the form of Hindi spoken in that neighbourhood was adopted by degrees as the basis of a new phase of the language, in which, though the inflections of nouns and verbs remained purely and absolutely Hindi, and a vast number of the commonest vocables were retained, a large quantity of Persian and Arabic and even Turkish words found a place, just as Latin and Greek words do in English. Such words, however, in no way altered or influenced the language itself, which, when its inflectional or phonetic elements are considered, remains still a pure Aryan dialect, just as pure in the pages of Wali or Sauda, as it is in those of Tulsi Das or Bihari Lal. It betrays therefore a radical misunderstanding of the whole bearings of the question, and of the whole science of philology, to speak of Urdu and Hindi as two distinct languages. When certain agitators cry out that the language of the English courts of law in Hindustan should be Hindi and not Urdu, what they mean is that clerks and native writers should be restrained from importing too many Persian and Arabic words into their writings, and should use instead the honest old Sanskrit Tadbhavas with which the Hindi abounds. By all means let it be so, only let it not be said that the Urdu is a distinct language from Hindi. [The most correct way of speaking would be to say "the Urdu dialect of Hindi," or "the Urdu phase of Hindi." It would be quite impossible in Urdu to compose a single sentence without using Aryan words, though many sentences might be composed in which not a single Persian word occurred.]
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{page 39}: By a curious caprice, Hindi, when it uses Arabic words, is assumed to become a new language, and is called by a new name - Urdu; but when Panjabi or Sindhi do the same, they are not so treated.

Further Reading

There are other published works that trace the development of Hindi/Urdu literature, the evolution of these two dialects under the Hindvi umbrella, and related topics.

Alok Rai, "The Persistence of Hindustani", The Annual of Urdu Studies, vol. 20, 2005, pp. 135-144.
T. Grahame Bailey, "Urdu: The Name and the Language", Journal of the Royal Asiatic Society of Great Britain and Ireland, no. 2, 1930, pp. 391-400.
T. Grahame Bailey, "The Pronunciation of Urdu and Hindi", Bulletin of the School of Oriental Studies, vol. 2(3), 1922, pp. 539-547.
Ralph Russell, "Some Notes on Hindi and Urdu", The Annual of Urdu Studies, vol. 11, 1996, pp. 203-208. (Russell advocates the two-language theory but largely on the basis that the standard/literary forms are mutually unintelligible. However, this is not the nominal linguistic consensus.)
David Lelyveld, "Zuban-e Urdu-e Mu`alla and the Idol of Linguistic Origins", The Annual of Urdu Studies, vol. 9, 1994, pp. 57-67.
Barz, Yadav, "An Introduction to Hindi and Urdu", Munshiram Manorharlal Publications, 2000.
Shackle, Snell, "Hindi and Urdu since 1800 - A common reader", Heritage Publishers, 1990.
Shantanu Phukan, "The Rustic Beloved: Ecology of Hindi in a Persianate World", The Annual of Urdu Studies, vol. 15, 2000, pp. 3-30.