The Lotus Sūtra of the fifth period consists of one fascicle of the Sūtra of Infinite Meaning as an introduction, eight fascicles of the Lotus Sūtra, and one fascicle of the Sūtra of Meditation on the Universal Sage Bodhisattva as the conclusion, bringing the total number of fascicles to ten.
The reason for my commentaries on the Four Teachings (Tripiṭaka, Common, Distinct, and Perfect) and the Four Periods (Flower Garland, Agama, Expanded, and Wisdom) is to help others learn what the Lotus Sūtra is. For one cannot correctly understand the teaching of the Lotus Sūtra without learning the pre-Lotus Sūtras, although one may study the pre-Lotus Sūtras without learning about other Sūtras.
In support of this, Grand Master T’ien-t’ai stated in his Profound Meaning of the Lotus Sūtra, “When attempting to spread various sūtras other than the Lotus Sūtra, the essential part of the teaching will not be lost even if a doctrinal analysis of all the teachings of the Buddha is not rendered. When attempting to spread the Lotus Sūtra, however, the essence of the teaching may be lost if a doctrinal analysis is not made.” It is preached in the Lotus Sūtra (chapter 2, “Expedients”), “Although the Buddhas expound various teachings, it is for the purpose of leading the people into the world of the One Buddha Vehicle.” “Various teachings” here refer to all the pre-Lotus Sūtras. “For the purpose of leading the people into the world of the One Buddha Vehicle” means to expound all the scriptures of Buddhism to reveal the Lotus Sūtra.
Ichidai Shōgyō Tai-I, Outline of All the Holy Teachings of the Buddha, Writings of Nichiren Shōnin, Doctrine 3, Page 81