Therefore, it is said that for the sake of Prince Otomo, whose mother is Iga no Ume, Emperor Tenchi made a law that dictates the direct line as the prerequisite of succession, and Empress Genmei took it up as Fukai-no-Joten/ Fukaijoten for the sake of Emperor Shomu, whose mother was from the Fujiwara clan.
そこで、伊賀采女を母に持つ大友皇子のために天智天皇が直系のみを条件とせよとする法を作り、元明天皇が藤原氏を母に持つ聖武天皇のためにこれを不改常典としてとり上げたとする。