Scholars have called attention to the Shoshin kangaku shō (Encouraging beginners in study), a Muromachi period introductory text written and studied at the Senba dangisho. Under the heading “Oneness of the true and provisional teachings,” it reads:

Right at hand we have the transmissions passed down from virtuous teachers of the past, who have said, “The Lotus Sūtra itself has no essence. It takes as its essence the teachings expounded before it.” Nonetheless, in the present age, the followers of Nichiren profoundly revere only the Lotus and deeply reject the teachings expounded before it. This is a grave error. While the Lotus is indeed to be revered, to slander other sutras in fact destroys the intent of the Lotus. …

Question: In their repudiation of the provisional teachings, we find that the Nichiren followers cite as their proof texts these passages from [the “Skillful Means” chapter] of the Lotus: “Honestly discarding skillful means, I will expound only the unexcelled Way” and “[There is the Dharma of only one vehicle, there are not two or three,] excepting the Buddha’s preaching of skillful means.” How do you respond?

Answer: When one reads the character for “to discard” (sha) in “hon estly discarding skillful means” as “to place” (oku), then it means that the skillful means of the provisional teachings, just as they are, are placed within the Lotus. This being the case, the fact that the “Skillful Means” chapter is placed among the [sūtra’s] twenty-eight chapters expresses the meaning of skillful means being precisely true reality. As for “excepting the Buddha’s preaching of skillful means,” this is interpreted to mean that attachment to these teachings is to be removed, not the dharma-teachings themselves. In other words, one is simply to remove emotional attachment to the [notion of] skillful means expounded before the Lotus as provisional teachings.

The Kantō Tendai of Senba and Hokke positions on this issue can be seen as representing two poles in the interpretation of the notion of kaie, or the “opening and integration” of all other teachings into the one vehicle of the Lotus Sūtra. The Senba side, as represented in the above passage from the Shoshin kangaku shō, took this to mean that since all teachings are encompassed by the one vehicle, to practice other teachings is in effect to practice the Lotus Sūtra. This interpretation is sometimes termed “absolute integration” (or zettai kaie) and has enjoyed a prominent place in the history of Japanese Tendai thought. The Hokke side, on the other hand, maintained that Lotus is, quite simply, superior to all other teachings; when integrated into it, they lose their separate identity. This is the interpretation of “relative integration” (sōtai kaie) that Nichiren had emphasized. The idea that all practices may be understood as aspects of the one vehicle and are thus the practice of the Lotus Sūtra had been well established in Tendai circles since Heian times. The invocation “Namu-Amida-butsu,” for example, was often referred to as the “six-character Lotus Sūtra.” The fact that the scholars of Senba felt compelled to argue this already well established position in such detail suggests that they were being hard pressed by their Hokke counterparts. (Page 307-308)