This second chapter of the Lotus Sūtra represents the Buddha as declaring, “I will now definitely expound the truth” and “having openly set aside skillful means, I will teach only the highest path.” These statements, together with the passage from the Lotus Sūtra’s introductory scripture, Sūtra of Immeasurable Meanings — “For more than forty years I have expounded the dharma in all manner of ways through adeptness in skillful means, but the core truth has still not been revealed” — constituted for Nichiren significant proof that the Lotus Sūtra superseded all prior, provisional teachings. They were, he said, like a great wind scattering dark clouds, the full moon appearing in the heavens, or the orb of the sun blazing in the blue sky, revealing the possibility of buddhahood for all.

The interpenetration of ten realms reveals that, in principle, there is no difference between an ordinary person and a buddha; both embody the three thousand realms in a single thought-moment. But in ordinary, deluded persons the buddha realm remains dormant and unrealized, and they are trapped by suffering. In the case of a buddha, the buddha realm is fully expressed; that is, all the other nine realms are illuminated, elevated, and redirected by it to work in an enlightened way. For Nichiren, this fully realized state was embodied in the daimoku. We could say that chanting the daimoku aligns or “syncs” the ten realms and three thousand realms of the practitioner with those of the Buddha, enabling direct realization in the very act of practice.

Like other Buddhists of his day, Nichiren understood the six paths as actual cosmological realms into which beings are born repeatedly in accordance with their deeds, and the four holy paths of śrāvakas, pratyekabuddhas, bodhisattvas, and buddhas, as higher states achieved through cultivation. But at the same time, he understood all ten realms as lying “within ourselves.” In his major treatise “On the Contemplation of the Mind and the Object of Worship” (Kanjin honzon shō), Nichiren explains this by way of illustration. When one looks at another person’s face, they appear sometimes ecstatic, sometimes furious, and sometimes calm, or they might wear expressions of foolishness or perversity. Rage, he explains, is the hell realm; greed, the realm of hungry ghosts; foolishness, the realm of beasts; perversity, the asura realm; joy, the heavenly realm; and calm, the human realm. The four holy paths do not appear outwardly but can be known by introspection. Our understanding that all things are insubstantial and fleeting reflects the realms of the two vehicles of śrāvakas and pratyekabuddhas within our own mind. The affection that even a hardened criminal feels for his wife and children is an expression of the inner bodhisattva realm. Because the nine realms within one’s own mind can thus be demonstrated, Nichiren says, one should believe that the buddha realm is present as well.

In the above quotation, “seeing” the Buddha in one’s mind might suggest a specific cognition or insight, but for Nichiren, this meant chanting the daimoku, the expression of faith in the Lotus Sūtra. Though he encouraged study and intellectual understanding of the Buddhist teachings, the benefits of the daimoku, he said, are the same whether chanted by a wise person or a foolish one. He illustrated this by the analogies of fire that burns without intent to do so, or a newborn infant nourished unknowingly by its mother’s milk. At the beginning of [Chapter 2], when Śākyamuni Buddha first begins to speak, his opening words are: “Profound and immeasurable is the wisdom of the buddhas.” “What is this wisdom?” Nichiren asks. “It is the embodiment of the real aspect of all dharmas, the ten suchnesses realized by the Buddha. What is that embodiment? It is Namu Myōhō-renge-kyō.”

Nichiren took the ichinen sanzen concept that Zhiyi had briefly delineated and made it the foundation of his teaching. For Nichiren, ichinen sanzen was “the father and mother of the buddhas.” He often referred to it in its “short form,” so to speak, as the mutual inclusion of the ten dharma realms… . Because the “ten suchnesses” (referred to at the beginning of the “Skillful Means” chapter) and the mutual inclusion of the ten realms are both concepts integral to the single thought-moment that is three thousand realms, the one implied the other, and Nichiren could take “the real aspect of all dharmas” or the ten suchnesses as pointing to the mutual inclusion of the ten realms. For him, this teaching was unique to the Lotus Sūtra and was what qualified it as the “wonderful dharma.” In one passage, he writes: “The sūtras that the Buddha preached for more than forty years before the Lotus do not set forth the mutual inclusion of the ten realms. And because they do not set forth the mutual inclusion of the ten realms, one cannot know the buddha realm within one’s own mind, and because one does not know the buddha realm within one’s own mind, the buddhas do not manifest externally either. … But now with the Lotus Sūtra, the buddha realm within the nine realms was opened, and those who had heard the Buddha’s forty and more years of preaching — bodhisattvas, persons of the two vehicles, and ordinary beings of the six paths — could for the first time see the buddha realm within themselves.”