Jōdai Tokushu Kanazukai
Jōdai Tokushu Kanazukai (上代特殊仮名遣?) is an archaic kana orthography system used to write Japanese during the Nara period. Its primary feature is to distinguish between two groups of syllables that later merged.
The existence and meaning of this system is a critical point of scholarly debate in the study of the history of the Japanese language.
The following are the syllabic distinctions made in Old Japanese.
Those syllables marked in gray are known as jōdai tokushu kanazukai.
The two groups merged by the 9th century. It predates the development of kana, and the phonetic difference is unclear. Therefore, an ad hoc transcription system is employed.
Syllables written with subscript 1 are known as type A (甲 kō?) and those with subscript 2 as type B (乙 otsu?) (these are the first two celestial stems, and are used for such numbering in Japanese).
There are several competing transcription systems. One popular system places a dieresis above the vowel: ï, ë, ö. This typically represents i2, e2, and o2, and assumes that unmarked i, e, and o are i1, e1, and o1. It does not necessarily have anything to do with pronunciation. There are several problems with this system.
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