In opposition to the commonly accepted theory, Takeshi UMEHARA adventurously studied and discussed other theories in his "Minasoko no uta: KAKINOMOTO no Hitomaro Ron" (Underwater poems: on KAKINOMOTO no Hitomaro).
その通説に梅原猛は『水底の歌－柿本人麻呂論』において大胆な論考を行った。