Classification of the Japonic languages
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The classification of the Japonic languages and their external relations is unclear. Linguists traditionally consider the Japonic languages to belong to an independent family; indeed, until the classification of Ryukyuan as separate languages within a Japonic family rather than as dialects of Japanese, Japanese was considered a language isolate.
Among more distant connections, the possibility of a genetic relationship to the non-Korean languages of southern Korea or languages like Austronesian and or Kra–Dai, are discussed. A relation between Japonic and Korean is also considered plausible by some linguists, while others reject any relation between Japonic and Korean. Independent of the question of a Japonic–Korean connection, both the Japonic languages and Korean were sometimes included in the largely discredited Altaic family.
- 1 Primary language family
- 2 Possible external relations
- 2.1 Japonic-Koreanic theory
- 2.2 Altaic theory
- 2.3 Proposals relating Japonic languages to Southeast Asian language families
- 3 Other hypotheses
- 4 See also
- 5 References
- 6 Bibliography
Primary language family
The currently most supported view is that the Japonic languages (sometimes also "Japanic") are their own primary language family, consisting of Japanese, Ryukyuan and Peninsular Japonic. The Hachijō language is sometimes classificated as fourth branch of the Japonic language family but currently seen as a very divergent dialect of Eastern Japanese.
It is suggested that the linguistic homeland of Japonic is located somewhere in south-eastern or eastern China before the proto-Japanese migrated to the Korean Peninsula and the Japanese archipelago. Miyamoto suggests a homeland further north, around modern day Beijing and Liaoning. Koreanic languages, then established in Manchuria expanded southward to the Korean peninsula, displacing Japonic languages that have been spoken there and causing the Yayoi migrations into Japan.
Vovin suggests that Japonic languages were spoken in parts of Korea, especially southern Korea, and were then replaced and assimilated from proto-Korean speakers. Similarly Whitman (2012) suggests that Japonic is not related to Korean but that Japonic was present on the Korean peninsula during the Mumun pottery period (Yayoi people). According to him, Japonic arrived in the Korean peninsula around 1500 BC and was brought to the Japanese archipelago by the Yayoi at around 950 BC. The language family associated with both Mumun and Yayoi culture is Japonic. Koreanic arrived later from Manchuria to the Korean peninsula at around 300 BC and coexist with the descendants of the Japonic Mumun cultivators (or assimilated them). Both had influence on each other and a later founder effect diminished the internal variety of both language families.
Most linguists today see the Japonic languages as own distinct family, not related to Korean, but acknowledge an influence from other language families (and vice versa). Vovin (2015) shows evidence that the early Koreans borrowed words for rice cultivation from Peninsular Japonic. According to him, the middle Korean word psʌr (rice) is loaned from Peninsular Japonic *wasar.
Possible external relations
There is disagreement over the protohistorical or historical period during which this expansion occurs, ranging from the Korean Bronze Age period to the Three Kingdoms of Korea period. As there is disagreement among experts when the expansion of Koreanic languages started, there is room for interpretation on the proto-historical and historical extent of the Japonic language presence in the central and southern Korean peninsula.
Similarities between Japanese and Koreanic languages
Japanese and Korean languages also share some typological similarities, such as an agglutinative morphology, a subject–object–verb (SOV) normal word order, important systems of honorifics (however, the two languages' systems of honorifics are different in form and usage; see Japanese honorifics and Korean honorifics), besides a few lexical resemblances. Factors like these led some historical linguists to suggest a genetic relationship between the two languages.
William George Aston suggested in 1879 in the Journal of the Royal Asiatic Society that Japanese is related to Korean. A relationship between Japanese and Korean was endorsed by the Japanese scholar Shōsaburō Kanazawa in 1910. Other scholars took this position in the twentieth century (Poppe 1965:137). Substantial arguments in favor of a Japanese–Korean relationship were presented by Samuel Martin, a leading specialist in Japanese and Korean, in 1966 and in subsequent publications (e.g. Martin 1990). Linguists who advocate this position include John Whitman (1985) and Barbara E. Riley (2004), and Sergei Starostin with his lexicostatistical research, The Altaic Problem and the Origins of the Japanese Language (Moscow, 1991). A Japanese–Korean connection does not necessarily exclude a Japanese–Koguryo or an Altaic relationship.
The two languages have previously been thought to not share any cognates (other than loanwords), for their vocabularies do not phonetically resemble each other. However, a recent 2016 paper proposing a common lineage between Korean and Japanese claims to trace around 500 core words that show a common origin including several numerals such as 5 and 10.
The possible lexical relationship between Korean and Japanese can be briefly exemplified by such basic vocabulary items as are found in the tables below.
|we||wuli||wareware, warera||The Japanese forms are plurals (by reduplication and suffixation, respectively) of Japanese first-person singular personal pronoun ware. The Korean form may be from an earlier *ur-hŭi, with -hŭi as in the second-person plural personal pronoun nə-hŭi and the humble first-person plural personal pronoun jə-hŭi, but the plain first-person singular personal pronoun in Korean is na rather than *ur.|
|not||ani, an||-na-, -nu|
|sun||hay||hi, -bi||IPA approximates /hɛ/ and /hi/, respectively. The Korean word may also mean "year." The Japanese word may also mean "day" or "fire."|
|to be hard||kut-||kata-|
Both languages also have similar elaborate, multilevel systems of honorifics. They are cited as the two most elaborate honorific systems, perhaps unrivaled by any other languages. It has been argued that certain honorific words share a common origin.
Martine Robbeets and Remco Bouckaert from the Max Planck Institute for the Science of Human History used in 2018 for the first time a Bayesian phylogenetic inference analysis about "Transeurasian". Their study resulted in a "high probability" for a "Koreano-Japonic" group, but has not gained acceptance among mainstream linguists.
This theory has been criticized for serious methodological flaws, such as rejecting mainstream reconstruction of Chinese and Japanese and using different owns[clarification needed] instead. Other critics, like Alexander Vovin and Toh Soo Hee, argued that the connections between Japanese and Goguryeo are due to earlier Japonic languages that were present in parts of Korea, and that the Goguryeo language was closer to Sillan and Korean. Further studies (2019) deny and criticize a relation between Korean and Japanese. Vovin also argues that the claimed cognates are nothing more than early loanwords from when Japonic was still spoken in southern Korea.
The idea of a Japanese–Korean relationship overlaps the extended form of the Altaic hypothesis (see below), but not all scholars who argue for one also argue for the other. For example, Samuel Martin, who was a major advocate of a Japanese–Korean relationship, only provided cautious support to the inclusion of these languages in Altaic, and Talat Tekin, an Altaicist, includes Korean, but not Japanese, in Altaic (Georg et al. 1999:72, 74).
Possible connection between Japonic and Koguryoic
The Japanese–Koguryoic proposal dates back to Shinmura Izuru's (1916) observation that the attested Goguryeo numerals—3, 5, 7, and 10—are very similar to Japanese. The hypothesis proposes that Japanese is a relative of the extinct languages spoken by the Buyeo-Goguryeo cultures of Korea, southern Manchuria, and Liaodong. The best attested of these is the language of Goguryeo, with the more poorly attested Koguryoic languages of Baekje and Buyeo believed to also be related.
A monograph by Christopher Beckwith (2004) has established about 140 lexical items in the Goguryeo corpus. They mostly occur in place-name collocations, many of which may include grammatical morphemes (including cognates of the Japanese genitive marker no and the Japanese adjective-attributive morpheme -sa) and a few of which may show syntactical relationships. He postulates that the majority of the identified Goguryeo corpus, which includes all of the grammatical morphemes, is related to Japanese.
The Altaic language family is a theoretical group composed of, at its core, languages categorized as Turkic, Mongolic, and Tungusic. G.J. Ramstedt's Einführung in die altaische Sprachwissenschaft ('Introduction to Altaic Linguistics') in 1952–1957 included Korean in Altaic. Roy Andrew Miller's Japanese and the Other Altaic Languages (1971) included Japanese in Altaic as well. The most important recent work that favored the expanded Altaic family (i.e. that Korean and Japanese could both be included under the Altaic language family) is An Etymological Dictionary of the Altaic Languages (3 volumes) by Sergei Starostin, Anna V. Dybo, and Oleg A. Mudrak (2003). Robbeets (2017) considers Japonic to be a "Transeurasian" (Altaic) language that is genetically unrelated to Austronesian, and argues that lexical similarities between Japonic and Austronesian are due to contact.
The Altaic proposal has largely been rejected (in both its core form of Turkic, Mongolic, and Tungusic as well as its expanded form that includes Korean and/or Japanese) but is still a discussed possibility. The best-known critiques are those by Gerard Clauson (1956) and Gerhard Doerfer (1963, 1988). Current critics include Stefan Georg and Alexander Vovin. Critics[who?] attribute the similarities in the putative Altaic languages to pre-historic areal contact having occurred between the languages of the expanded group (e.g. between Turkic and Japonic), contact which critics and proponents agree took place to some degree.
However, linguists agree today that typological resemblances between Japanese, Korean and Altaic languages cannot be used to prove genetic relatedness of languages,[failed verification] as these features are typologically connected and easily borrowed from one language to the other (e.g. due to geographical proximity with Manchuria). Such factors of typological divergence as Middle Mongolian's exhibition of gender agreement can be used to argue that a genetic relationship with Altaic is unlikely.[failed verification]
According to Robbeets (2017) Japanese (and Korean) originated as a hybrid language, in the today Liaoning province, between an Austronesian-like language and Altaic (Transeurasian) elements. She suggests that proto-Japanese had an additional influence from Austronesian on the Japanese archipelago.
She lists the following agricultural vocabulary in proto-Japonic with parallels in Austronesian languages:
- proto-Japonic *kəmai ‘dehusked rice’
- proto-Austronesian *Semay ‘cooked rice’
- Old Chinese 糜 *C.maj ‘rice gruel; destroy, crush’
- early ripening crop
- proto-Japonic *wasara ~ *wǝsǝrǝ ‘early ripening crop, early ripening rice’
- proto-Austronesian *baCaR ‘broomcorn millet (Panicum miliaceum)’
- proto-Koreanic *pʌsal ‘hulled variety of grain, rice’
But her view is not uncontroversial as she takes the Altaic/Transeurasian theory for granted.
Proposals relating Japonic languages to Southeast Asian language families
Several linguists have proposed that the Japonic language are genetically related to the Austronesian languages. Some linguists think it is more plausible that Japanese was instead influenced by Austronesian languages, perhaps by an Austronesian substratum. Those who propose the latter scenario suggest that the Austronesian family once covered most of southern Japan. The phonological similarities of Japanese to the Austronesian languages, and the geographical proximity of Japan to Formosa and the Malay Archipelago have led to the theory that Japanese may be a kind of mixed language, with a Korean (or Altaic) superstratum and an Austronesian substratum.
Similarly Juha Janhunen claims that Austronesians lived in southern Japan, specifically on Shikoku, and that modern Japanese has an "Austronesian layer". The linguist Ann Kumar (2009) believes that some Austronesians migrated to early Japan, possibly an elite group from Java, and created the "Japanese-hierarchical society", and identifies 82 plausible cognates between Austronesian and Japanese. The morphology of Proto-Japanese shows similarities with several languages in South East Asia and southern China.
Itabashi (2011) claims that similarities in morphology, phonology and basic vocabulary point towards "a strong genealogical connection between Japanese and Austronesian".
Paul K. Benedict (1992) suggests a genetic relation between Japanese and the Austro-Tai languages, which include Kra-Dai and Austronesian. He proposes that Kra-Dai and Japanese form a genetic mainland group while Austronesian is the insular group.
Vovin (2014) says that there is typological evidence that Proto-Japonic may have been a monosyllabic, SVO syntax and isolating language; which are features that the Kra-Dai languages also exhibit. He notes that Benedict's idea of a relation between Japanese and Kra-Dai should not be rejected out of hand, but he considers the relationship between them not to be genetic, but rather a contact one. According to him, this contact must be quite old and quite intense, as the borrowed words belong partially to a very basic vocabulary. He further says that this evidence refutes any genetic relations between Japanese and Altaic.
Possible Austroasiatic substrate
- *(z/h)ina-Ci 'rice (plant)'
- koma-Ci '(hulled) rice'
- pwo 'ear of grain'
According to him early Japanese assimilated Austroasiatic tribes and adopted some vocabulary about rice cultivation. On the other hand, John Whitman (2011) does not support that this words were loanwords into proto-Japonic, but that these words are of Japonic origin and must be rather old.
A 2015 analysis using the Automated Similarity Judgment Program resulted in support for an Austroasiatic-Japonic link. The study did not find evidence for a relation to Altaic languages. According to this analysis, Japanese has its closest linguistic relation with Austroasiatic languages, such as Khmer and Vietnamese. Note however that ASJP is not widely accepted among historical linguists as an adequate method to establish or evaluate relationships between language families.
Another theory was raised by the Japanese linguist Īno Mutsumi (1994). According to him, Japanese is closely related to the Sino-Tibetan languages, especially to the Lolo-Burmese languages of southern China and Southeast-Asia. Because of similar grammar rules (SOV word order, syntax), similar non-loan basic vocabulary and the fact that some Sino-Tibetan languages (including proto-Sino-Tibetan) were non-tonal, he proposed the "Sinitic" origin theory.
The “Proto-Asian hypothesis” (Larish 2006) argues for a relation between languages of Southeast and East Asia. Japanese is grouped together with Korean as one group of the descendants of Proto-Asian. The proposal further includes the Austric languages, Kra-Dai, Hmong-Mien and Sino-Tibetan
A more rarely encountered hypothesis is that Japanese (and Korean) are related to the Dravidian languages. The possibility that Japanese might be related to Dravidian was raised by Robert Caldwell (cf. Caldwell 1875:413) and more recently by Susumu Shiba, Akira Fujiwara, and Susumu Ōno (n.d., 2000). The Japanese professor Tsutomu Kambe claimed to have found more than 500 similar words about agriculture between Tamil and Japanese in 2011.
The Japanese linguist Kanehira Joji believes that the Japanese language is related to the Uralic languages. He based his hypothesis on some similar basic words, similar morphology and phonology. According to him early Japanese got influenced from Chinese, Austronesian and Ainu. He refers his theory to the “dual-structure model” of Japanese origin between Jōmon and Yayoi.
The Japanese linguist Tatsumine Katayama (2004) found many similar basic words between Ainu and Japanese. Because of a great amount of similar vocabulary, phonology, similar grammar, and geographical and cultural connections, he and Takeshi Umehara suggested that Japanese was closely related to the Ainu languages, and was influenced by other languages, especially Chinese and Korean.
A linguistic analysis in 2015 resulted in the Japonic languages being related with the Ainu languages and to the Austroasiatic languages. However, similarities between Ainu and Japonic are also due to extensive past contact. Analytic grammatical constructions acquired or transformed in Ainu were likely due to contact with Japanese and the Japonic languages, which had heavy influence on the Ainu languages with a large number of loanwords borrowed into the Ainu languages, and to a smaller extent, vice versa.
- Linguistic reconstruction
- Comparison of Japanese and Korean
- Common words for Korean and Japanese, mostly loanwords found.
- Eurasiatic languages
- Nostratic languages
- Proto-Korean-Japanese: A New Reconstruction of the Common Origin of the Japanese and Korean Languages, by Alexander Takenobu Francis-Ratte
- Vovin, Alexander (2013). "From Koguryo to Tamna: Slowly riding to the South with speakers of Proto-Korean". Korean Linguistics. 15 (2): 222–240.
- "While 'Altaic' is repeated in encyclopedias and handbooks most specialists in these languages no longer believe that the three traditional supposed Altaic groups, Turkic, Mongolian and Tungusic, are related." Lyle Campbell & Mauricio J. Mixco, A Glossary of Historical Linguistics (2007, University of Utah Press), pg. 7.
- "When cognates proved not to be valid, Altaic was abandoned, and the received view now is that Turkic, Mongolian, and Tungusic are unrelated." Johanna Nichols, Linguistic Diversity in Space and Time (1992, Chicago), pg. 4.
- "Careful examination indicates that the established families, Turkic, Mongolian, and Tungusic, form a linguistic area (called Altaic)...Sufficient criteria have not been given that would justify talking of a genetic relationship here." R.M.W. Dixon, The Rise and Fall of Languages (1997, Cambridge), pg. 32.
- "...[T]his selection of features does not provide good evidence for common descent....we can observe convergence rather than divergence between Turkic and Mongolic languages--a pattern than is easily explainable by borrowing and diffusion rather than common descent," Asya Pereltsvaig, Languages of the World, An Introduction (2012, Cambridge). This source has a good discussion of the Altaic hypothesis on pp. 211-216.
- Thomas Pellard. The comparative study of the Japonic languages. Approaches to endangered languages in Japan and Northeast Asia: Description, documentation and revitalization, National Institute for Japanese Language and Linguistics, Aug 2018, Tachikawa, Japan. ffhal-01856152
- Vovin, Alexander. "Origins of the Japanese Language". Cite journal requires
- Vovin, Alexander. 2014. "Out of Southern China? – Philological and linguistic musings on the possible Urheimat of Proto-Japonic". Presentation given at Journées de CRLAO 2014. June 27–28, 2014. INALCO, Paris.
- RECONSTRUCTING THE LANGUAGE MAP OF PREHISTORICAL NORTHEAST ASIA - Juha Janhunen Studia Orientalia 108 (2010)
- Lee Sean; Hasegawa Toshikazu (2011-12-22). "Bayesian phylogenetic analysis supports an agricultural origin of Japonic languages". Proceedings of the Royal Society B: Biological Sciences. 278 (1725): 3662–3669. doi:10.1098/rspb.2011.0518. PMC 3203502. PMID 21543358.
- Bellwood, Peter (2013). The Global Prehistory of Human Migration. Malden: Blackwell Publishing. ISBN 9781118970591.
- Archaeological Explanation for the Diffusion Theory of the Japonic and Koreanic Languages - MIYAMOTO Kazuo
- Lee, Ki-Moon; Ramsey, S. Robert (2011). A History of the Korean language. Cambridge: Cambridge University Press. ISBN 978-0-521-66189-8.
- Whitman, John (2011). "Northeast Asian Linguistic Ecology and the Advent of Rice Agriculture in Korea and Japan". Rice. 4 (3–4): 149–158. doi:10.1007/s12284-011-9080-0.
- Unger, J. Marshall (2009). The role of contact in the origins of the Japanese and Korean languages. Honolulu: University of Hawai?i Press. ISBN 978-0-8248-3279-7.
- Whitman, John (2011-12-01). "Northeast Asian Linguistic Ecology and the Advent of Rice Agriculture in Korea and Japan". Rice. 4 (3): 149–158. doi:10.1007/s12284-011-9080-0. ISSN 1939-8433.
- Vovin, Alexander. "On The Etymology of Middle Korean psʌr 'rice'". Cite journal requires
- Sohn (2001), p. 29.
- Kornicki, Peter (December 2005). "Aston, Cambridge and Korea" (PDF). Archived from the original (PDF) on May 29, 2008.
- Martin 1966, 1990
- Takenobu, Francis-Ratte, Alexander (2016). Proto-Korean-Japanese: A New Reconstruction of the Common Origin of the Japanese and Korean Languages (Thesis). The Ohio State University.
- Brown, Lucien (2008). "Contrasts Between Korean and Japanese Honorifics". Rivista Degli Studi Orientali. 81 (1/4): 369–385. JSTOR 41913346.
- "Grammaticalization in Sentence-Final Politeness Marking in Korean and Japanese".
- Robbeets, Bouckaert, Martine, Remco (2018). "Bayesian phylolinguistics reveals the internal structure of the Transeurasian family". Journal of Language Evolution.
- Pellard, Thomas (2005). "Koguryo, the Language of Japan's Continental Relatives: An Introduction to the Historical-Comparative Study of the Japanese-Kgouryoic Languages with a Preliminary Description of Archaic Northeastern Middle Chinese (review)" (PDF). Korean Studies. 29: 167–170. doi:10.1353/ks.2006.0008.
- Toh Soo-Hee (2005). "About Early Paekche Language Mistaken as Being Koguryo Language". Journal of Inner and East Asian Studies. 2(2): 10–31.
- Vovin, Alexander (26 September 2017). "Origins of the Japanese Language". Oxford Research Encyclopedia of Linguistics. Oxford University Press. doi:10.1093/acrefore/9780199384655.013.277. Retrieved 29 November 2019.
- Shinmura, Izuru (1916). "國語及び朝 鮮語の數詞について [Regarding numerals in Japanese and Korean]". Geibun. 7.2-7.4.
- Vovin 2008: 1
- Trask 1996: 147–51
- Rybatzki 2003: 57
- Vovin 2008: 5
- Robbeets, Martine (2017). "Austronesian influence and Transeurasian ancestry in Japanese: A case of farming/language dispersal". Language Dynamics and Change. 7 (2): 210–251. doi:10.1163/22105832-00702005.
- Benedict (1990), Matsumoto (1975), Miller (1967).
- Lewin (1976), Matsumoto (1975), Miller (1967), Murayama (1976).
- ユハ・ヤンフネン 「A Framework for the Study of Japanese Language Origins」『日本語系統論の現在』(pdf) 国際日本文化センター、京都、2003年、477-490頁。
- Kumar, Ann (2009). Globalizing the Prehistory of Japan: Language, Genes and Civilization. Oxford: Routledge.
- Vovin, Alexander (2008). "Proto-Japanese beyond the accent system". In Frellesvig, Bjarne; Whitman, John (eds.). Proto-Japanese: Issues and Prospects. Current Issues in Linguistic Theory. 294. John Benjamins. pp. 141–156. doi:10.1075/cilt.294.11vov. ISBN 978-90-272-4809-1.
- Itabashi, Yoshizo (April 2011). "An examination of a possible correlation between the tone distinction of the word-initial mora of Old-Japanese words and the voicing distinction of the word-initial consonant of the putative matching Austronesian words" (PDF). Language and Lingustics in Oceania. 3. Archived from the original (PDF) on 2019-04-23. Retrieved 2019-04-23.
- Solnit, David B. (1992). "Japanese/Austro-Tai By Paul K. Benedict (review)". Language. 68 (1): 188–196. doi:10.1353/lan.1992.0061. ISSN 1535-0665.
- Vovin, Alexander (1998). "Japanese rice agriculture terminology and linguistic affiliation of Yayoi culture". In Blench, Roger; Spriggs, Matthew (eds.). Archaeology and Language II: Archaeological Data and Linguistic Hypotheses. Routledge. pp. 366–378. ISBN 9781134828692.
However, the above evidence suggests that mounted invaders from the mainland subjugated the native Yayoi population once and for all, assimilating them linguistically... (Page 375 and 376)
- Jäger, Gerhard (2015). "Support for linguistic macrofamilies from weighted sequence alignment". PNAS. 112 (41): 12752–12757. Bibcode:2015PNAS..11212752J. doi:10.1073/pnas.1500331112. PMC 4611657. PMID 26403857.
- Cf. comments by Adelaar, Blust and Campbell in Holman, Eric W., et al. (2011) "Automated Dating of the World’s Language Families Based on Lexical Similarity." Current Anthropology, vol. 52, no. 6, pp. 841–875.
- 飯野睦毅 (1994)『奈良時代の日本語を解読する』東陽出版
- Taw Sein Ko 1924, p. viii.
- Larish, Michael D. (January 2006). Possible Proto-Asian Archaic Residue and the Statigraphy of Diffusional Cumulation in Austro-Asian Languages (PDF). Tenth International Conference on Austronesian Linguistics. Retrieved 2019-01-07.
- "Researchers find Tamil connection in Japanese - Times of India". The Times of India. Retrieved 2017-05-21.
- "日本語の意外な歴史" (in Japanese). Retrieved 2018-08-21.
- 日本語の意外な歴史 第1話 金平譲司 Joji Kanehira
- Tatsumine Katayama (2004) "Japanese and Ainu (new version)" Tokyo: Suzusawa library
- Gerhard Jäger, "Support for linguistic macrofamilies from weighted sequence alignment." PNAS vol. 112 no. 41, 12752–12757, doi: 10.1073/pnas.1500331112. Published online before print September 24, 2015.
- Tranter, Nicolas (25 June 2012). The Languages of Japan and Korea. Routledge. ISBN 9781136446580. Archived from the original on 30 July 2017 – via Google Books.
- Vovin, Alexander. 2016. "On the Linguistic Prehistory of Hokkaidō." In Crosslinguistics and linguistic crossings in Northeast Asia: papers on the languages of Sakhalin and adjacent regions (Studia Orientalia 117).
- Aston, William George (1879). "A comparative study of the Japanese and Korean languages". Journal of the Royal Asiatic Society of Britain and Ireland, New Series. 11: 317–364. doi:10.1017/s0035869x00017305.
- Beckwith, Christopher I. 2004. Koguryo: The Language of Japan's Continental Relatives: An Introduction to the Historical-Comparative Study of the Japanese-Koguryoic Languages. Leiden: Brill.
- Beckwith, Christopher I (2005). "The ethnolinguistic history of the early Korean peninsula region: Japanese-Koguryŏic and other languages in the Koguryŏ, Paekche, and Silla kingdoms" (PDF). Journal of Inner and East Asian Studies. 2 (2): 34–64. Archived from the original (PDF) on 2009-02-26.
- Beckwith, Christopher I (2006). "Methodological observations on some recent studies of the early ethnolinguistic history of Korea and vicinity". Altai Hakpo. 16: 199–234.
- Benedict, Paul K. 1990. Japanese/Austro-Tai. Ann Arbor: Karoma.
- Caldwell, Robert. 1875. A Comparative Grammar of the Dravidian or South-Indian Family of Languages, second edition. London: Trübner.
- Georg, Stefan, Peter A. Michalove, Alexis Manaster Ramer, and Paul J. Sidwell. 1999. "Telling general linguists about Altaic." Journal of Linguistics 35, 65-98. Cambridge: Cambridge University Press.
- Greenberg, Joseph H. 2000–2002. Indo-European and Its Closest Relatives: The Eurasiatic Language Family, 2 volumes. Stanford: Stanford University Press.
- Greenberg, Joseph H. 2005. Genetic Linguistics: Essays on Theory and Method, edited by William Croft. Oxford: Oxford University Press.
- Kanazawa, Shōsaburō. 1910. The Common Origin of the Japanese and Korean Languages. Tokyo: Sanseidō.
- Lewin, Bruno (1976). "Japanese and Korean: The Problems and History of a Linguistic Comparison". Journal of Japanese Studies. 2 (2): 389–412. doi:10.2307/132059. JSTOR 132059.
- Martin, Samuel E (1966). "Lexical evidence relating Korean to Japanese". Language. 12 (2): 185–251. doi:10.2307/411687. JSTOR 411687.
- Matsumoto, Katsumi. 1975. "Kodai nihongoboin soshikikõ: naiteki saiken no kokoromi". Bulletin of the Faculty of Law and Letters (Kanazawa University) 22.83–152.
- Martin, Samuel E. 1990. "Morphological clues to the relationships of Japanese and Korean." In Linguistic Change and Reconstruction Methodology, edited by Philip Baldi. Berlin:de Gruyter.
- Miller, Roy Andrew. 1971. Japanese and the Other Altaic Languages. Chicago: University of Chicago Press.
- Miller, Roy Andrew. 1967. The Japanese language. Chicago: University of Chicago Press.
- Murayama, Shichiro (1976). "The Malayo-Polynesian Component in the Japanese Language". Journal of Japanese Studies. 2 (2): 413–436. doi:10.2307/132060. JSTOR 132060.
- Ōno, Susumu. n.d. "The genealogy of the Japanese language: Tamil and Japanese."
- Ōno, Susumu. 2000. 日本語の形成. 岩波書店. ISBN 4-00-001758-6.
- Poppe, Nicholas. 1965. Introduction to Altaic Linguistics. Wiesbaden: Otto Harrassowitz.
- Riley, Barbara E. 2003. Aspects of the Genetic Relationship of the Korean and Japanese Languages. PhD thesis, University of Hawaii.
- Shibatani, Masayoshi. 1990. The languages of Japan. Cambridge: Cambridge UP.
- Starostin, Sergei A. 1991. Altajskaja problema i proisxoždenie japonskogo jazyka, 'The Altaic Problem and the Origin of the Japanese Language'. Moscow: Nauka.
- Starostin, Sergei A., Anna V. Dybo, and Oleg A. Mudrak. 2003. Etymological Dictionary of the Altaic Languages, 3 volumes. Leiden: Brill. (Also: database version.)
- Trombetti, Alfredo. 1922–1923. Elementi di glottologia, 2 volumes. Bologna: Nicola Zanichelli.
- Vovin, Alexander. 2003. 日本語系統論の現在：これからどこへ 'The genetic relationship of the Japanese language: Where do we go from here?'. In 日本語系統論の現在 'Perspectives on the Origins of the Japanese Language', edited by Alexander Vovin and Toshiki Osada. Kyoto: International Center for Japanese Studies. ISSN 1346-6585.
- Whitman, John Bradford. 1985. The Phonological Basis for the Comparison of Japanese and Korean. PhD thesis, Harvard University.
- Francis-Ratte, Alexander Takenobu. 2016. Proto-Korean-Japanese: A New Reconstruction of the Common Origin of the Japanese and Korean Languages. PhD dissertation: Ohio State University.
- Janhunen, Juha (2003). "A Framework for the Study of Japanese Language Origins" (PDF). In Vovin, Alexander; Osada, Toshiki (eds.). Nihongo keitōron no ima 日本語系統論の現在 [Perspectives on the Origins of the Japanese Language]. International Research Center for Japanese Studies. pp. 477–490. ISBN 978-4-9015-5817-4.
- Katsumi, Matsumoto. 2007. 世界言語のなかの日本語 Sekaigengo no nakano Nihongo, 'Japanese in the World's Languages'. Tokyo: 三省堂 Sanseido.
- Lewin, Bruno (1976). "Japanese and Korean: The problems and history of a linguistic comparison". Journal of Japanese Studies. 2 (2): 389–412. doi:10.2307/132059. JSTOR 132059.
- Martin, Samuel E. 1968. "Grammatical elements relating Korean to Japanese." In Proceedings of the Eighth Congress of Anthropological and Ethnological Sciences B.9, 405-407.
- Martin, Samuel E. 1975. "Problems in establishing the prehistoric relationships of Korean and Japanese." In Proceedings, International Symposium Commemorating the 30th Anniversary of Korean Liberation. Seoul: National Academy of Sciences.
- Martin, Samuel E. 1991. "Recent research on the relationships of Japanese and Korean." In Sprung from Some Common Source: Investigations into the Prehistory of Languages, edited by Sydney M. Lamb and E. Douglas Mitchell. Stanford: Stanford University Press.
- Martin, Samuel E. 1996. Consonant Lenition in Korean and the Macro-Altaic Question. Honolulu: University of Hawaii Press.
- Miller, Roy Andrew. 1980. Origins of the Japanese Language: Lectures in Japan during the Academic Year 1977-78. Seattle: University of Washington Press.
- Miller, Roy Andrew. 1996. Languages and History: Japanese, Korean and Altaic. Oslo: Institute for Comparative Research in Human Culture.
- Robbeets, Martine. 2004a. "Belief or argument? The classification of the Japanese language." Eurasia Newsletter 8. Graduate School of Letters, Kyoto University.
- Robbeets, Martine. 2004b. "Swadesh 100 on Japanese, Korean and Altaic." Tokyo University Linguistic Papers, TULIP 23, 99–118.
- Robbeets, Martine. 2005. Is Japanese related to Korean, Tungusic, Mongolic and Turkic? Wiesbaden: Otto Harrassowitz.
- Robbeets, Martine (2007). "How the actional suffix chain connects Japanese to Altaic". Turkic Languages. 11 (1): 3–58.
- Unger, J. Marshall (2014). "No rush to judgment: the case against Japanese as an isolate". NINJAL Project Review. 4 (3): 211–230. doi:10.15084/00000755.