Question: Is the doctrine of the Lotus School based on the explanations of Grand Masters T’ien-t’ai, Miao-lê and Dengyō?

Answer: It is based on the clear mirror of Śākyamuni Buddha (the Lotus Sūtra) supplemented by their explanations.

Shoshū Mondō-shō, Questions and Answers Regarding Other Schools, Writings of Nichiren Shōnin, Doctrine 3, Page 176