Re: Was there a “continental Japanese”?
The term relative, in parlance of Academe, implies that study of the origin of Japanese can be equated with a quest for a family tree of languages à l'Indo-Europrean wherein Japanese is a branch of. Ever since Altaic theory was considered largely defunct, this approach is not very popular. Recent studies on the origin of Japanese allow a lot of room for mixed languages and creolisation or both; neither of which can be supported or refuted from the perspective of traditional comparative linguistics (family tree model). A standard view in Japanese academic circles is that Japanese was developed as a mixed language between an Austronesian substratum and an Altaic (or "Northern" by the more doubtful) superstratum. None the better for the general agreement, different researchers propose lists of correspondence that do not agree with each other.
Originally Posted by Anatoli
Beckwith's list of Koguryo vocabulary finds that traditional comparative approach is insufficient for Koguryo classification; little or no relation to Altaic or Korean.
That Koguryo has the strongest similarity with Japanese is further explored by Yoshizō Itabashi:
（アレキサンダー・ボビン/長田俊樹共編 日文研叢書31『日本語系統論の現在』所収 2003年12月 国際日本文化研究センター）.
Itabashi (2003) is based on research by several Japanese Altaic experts dating back to 1970s. An earlier paper by Beckwith is considered as well. Koguryo documents were surveyed to extract 115 Koguryo words. Out of the extracted items, 71 were determined to have cognates in other languages. The number of cognates with Japanese is 47, that with Korean is 32, that with Tungusic languages is 25, and that with Austronesian languages is 8 (categorisation not mutually exclusive). In contrast to Beckwith, Koguryo's relation with Korean is not refuted. Itabashi concludes (the excogitation between the list and the conclusion is beyond my understanding) that Koguryo and Japanese have the closest relationship but the relatedness of the former to Korean cannot be neglected.
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