As described below, it can be said that Umayadono-Oji (Prince Umayado) is a different person from `Hiizurutokoronotenshi' (Prince Shotoku), and `Hiizurutokoronotenshi' was a person of the Kyushu dynasty who was deeply devoted to Kan I junikai (twelve grades of cap rank), the establishment of the Seventeen Article Constitution, the dispatch of Ken-suishi, and Buddhism.
以下のことから厩戸王子と「日出處天子」（聖徳太子）は別人であり、「日出處天子」は九州王朝の人物で、冠位十二階、憲法十七条制定、遣隋使派遣、仏教に深く帰依した。