In his works 'Himitsu Mandala Jujushinron' and 'Hizohoyaku,' Kukai expressed appreciation for another Buddhist sect, Dharma, which was at that time established to some extent, and built that thinking into a rating system of 1 to 10 by placing the Shingon sect above the Dharma.
空海は著作「秘密曼荼羅十住心論」（ひみつまんだらじゅうじゅうしんろん）、「秘蔵宝鑰」（ひぞうほうやく）で、空海が執筆していた当時に伝来していた仏教各派の教学に一応の評価を与えつつ、真言宗を最上位に置くことによって十段階の思想体系の中に組み込んだ。