In “The Heritage of the Ultimate Law of Life,” the Daishonin says that through the spirit of faith of many in body but one on mind, “even the great desire for widespread propagation can be fulfilled” (WND, 217). And in “Many in Body, One in Mind,” he states that his followers “will definitely accomplish their great mission of widely propagating the Lotus Sutra” (WND, 618) through the unity of many in body, one in mind.
In light of these passages, it is clear that “mind” means faith aimed at realizing kosen-rufu. Kosen-rufu is the great wish of the Buddha who seeks to lead all people to enlightenment. It is the cornerstone of the Lotus Sutra. “One in mind” means making this great wish of the Buddha one’s own and courageously working for kosen-rufu.

This guidance is an abstract from 'The World of Nichiren Daishonin Writings' with universal value and application

Nichiren Daishonin’s life flows in the Soka Gakkai, the organization dedicated to accomplishing kosen-rufu, the Buddha’s will and decree. The lifeblood of the Daishonin and the heritage of faith are found only in the harmonious community of practitioners that is the Soka Gakkai.
To protect the Soka Gakkai is to protect the heritage of the Daishonin’s faith. It is to cause the lifeblood of faith to flow in one’s own life. Only in the Soka Gakkai is the practice of the correct teaching of Buddhism found.

This guidance is an abstract from 'The World of Nichiren Daishonin Writings' with universal value and application

President Makiguchi stated the following in the guiding principles of the Soka Kyoiku Gakkai: “The Soka Kyoiku Gakkai shall neither be a gathering devoted to selfish individualism based on a myopic worldview that ignores the welfare of others, nor a gathering ruled by the fallacious dictates of totalitarianism that divests the individual of his identity. Instead, it shall take as its highest honor to be a living testimony to a truly holistic way of life that is based on a correct and undistorted worldview, and that aspires for both the self and others to dwell peacefully in a Land of Tranquil Light.”
By “myopic worldview,” he meant the egoism to think only about personal gain. “Totalitarianism,” on the other hand, indicated the sacrifice of the individual for the sake of one’s state or ethnic group. In contrast to these, the “correct and undistorted worldview” that President Makiguchi espoused referred to the path of striving for the happiness of oneself and others. By “holistic way of life” he meant creating harmony between the individual and the whole. He was talking about a situation in which each person, while bringing his or her potential to full bloom, strives at the same time to contribute to the peace and prosperity of society in its entirety.
President Makiguchi did not stop at mere ideals; rather, he aimed to realize them in society and prove their validity. He understood that this was possible through the Daishonin’s Buddhism, the great teaching of value-creation that reveals the fundamental Law of life. Herein lies the departure point of the Soka Gakkai.

This guidance is an abstract from 'The World of Nichiren Daishonin Writings' with universal value and application

The Soka Gakkai is neither held together by economic interest nor controlled by power. It is the embodiment of the essence of humanity united by the great ideal of realizing the widespread propagation of the Daishonin’s Buddhism, a teaching that brings the potential of the individual to shine. It is the crystallization of profound heart-to-heart bonds of trust.

This guidance is an abstract from 'The World of Nichiren Daishonin Writings' with universal value and application

Many in body, one in mind is indeed the supreme organizational principle that cherishes each individual. It enables all people to realize their full potential.
“Many in body” reflects the understanding that each of us has a unique mission, talent and set of circumstances. “One in mind” means that, despite our individuality, we need to unite in spirit.
In contrast, “many in body and many in mind” is utter disunity, while “one in body and one in mind” is group thinking in which individuality is ignored and totalitarianism ultimately results. Neither situation allows people to manifest their unique abilities.

This guidance is an abstract from 'The World of Nichiren Daishonin Writings' with universal value and application