While [Nichiren’s] single-practice orientation is itself open to criticism for the ease with which it can translate into dogmatic self-assertion, such observations miss the underlying logic of Nichiren’s aim. This appears to have been not to eradicate the spectrum of religious interpretations current in his day, but to undercut their bases in other traditions and assimilate them to the Lotus Sūtra. This is illustrated in the following passage:

Once they enter the great ocean of the Lotus Sūtra, the teachings preached before the Lotus are no longer shunned as provisional. It is the mysterious virtue of the great ocean of the Lotus Sūtra that, once they are encompassed in the single flavor of Namu-myōhō-renge-kyō, there is no longer any reason to refer to the distinct names “nenbutsu, ” “precepts,” “shingon, ” or “Zen.” Thus the commentary states, “When the various rivers enter the sea, they assume the same unitary salty flavor. When the various kinds of wisdom [represented by the provisional teachings] enter the true teaching, they lose their original names.

Nichiren’s teaching is no less exclusivistic for its attempt to be all-encompassing, but it should be understood as one of a number of contemporaneous attempts at subsuming all teachings, virtues, and possibilities within a single formulation. (Page 297)