Ikeda changed the very fundamentals of Nichiren Lotus Sutra Buddhism

"To merely repeat the four dictums simply because they came from the Daishonin, while ignoring people’s feelings and the changing times, is to overlook the Daishonin’s spirit. The four dictums are then nothing but dogma. That is what gives rise to the devilish aspects of religion. It is people and the heart that count. The four dictums are the manifestation of the Daishonin’s firm conviction to resolutely battle the devilish functions that serve to confuse people." -- Daisaku Ikeda

Nichiren writes: 

"...I say that the non-Buddhist scriptures are easier to believe and understand than the Hinayana sutras, the Hinayana sutras are easier than the Mahāvairochana and other [Correct and Equal] sutras, the Mahāvairochana and other sutras are easier than the Wisdom sutras, the Wisdom sutras are easier than the Flower Garland Sutra, the Flower Garland is easier than the Nirvana Sutra, the Nirvana is easier than the Lotus Sutra, and the theoretical teaching of the Lotus is easier than the essential teaching. Thus there are many levels of comparative ease and difficulty.

Question: What is the significance of knowing them?

Answer: The great lantern that illuminates the long night of the sufferings of birth and death, the sharp sword that severs the fundamental darkness inherent in life, is none other than the Lotus Sutra. The teachings of the True Word, Flower Garland, and other schools are categorized as those expounded in accordance with the people’s capacity. They are, therefore, easy to believe and understand. The teachings expounded in accordance with the people’s capacity are the sutras that the Buddha preached in response to the wishes of the people of the nine worlds, just as a wise father instructs an ignorant son in a way suited to the child’s understanding. On the other hand, the teaching expounded in accordance with the Buddha’s enlightenment is the sutra that the Buddha preached directly from the world of Buddhahood, just as a sage father guides his ignorant son to his own understanding.

In the light of this principle, I have carefully considered the Mahāvairochana, Flower Garland, Nirvana, and other [provisional] sutras, only to find that all of them are sutras expounded in accordance with the people’s capacity."

and again:

"Again, someone might object, saying: “Rather than insisting on preaching the Lotus Sutra when it does not accord with the people’s capacity, and thus causing them to slander it so that they fall into the evil paths, it would be better to preach the Nembutsu, which does suit their capacity, and thus awaken in them the aspiration for enlightenment. If someone not only fails to bring benefit to others, but on the contrary causes them to commit slander and fall into hell, he is no votary of theLotus Sutra but rather a person of false views.”

In reply to such objections, you should point out that in the Lotus Sutra the Buddha states that, whatever the people’s capacity may be, in the Latter Day of the Law one should persist in preaching the Lotus Sutra. Ask the questioner how he interprets that injunction. Does he claim that Shakyamuni Buddha, Bodhisattva Never Disparaging, T’ien-t’ai, Miao-lo, and Dengyō are persons of false views or non-Buddhists?

Then again, with regard to persons of the two vehicles, who have not fallen into the evil paths and have also escaped from rebirth in the threefold world, the Buddha declares that it is better to arouse in oneself the mind of a dog or a fox than to have the mind of the two vehicles. He also warns that it is better to commit the five cardinal sins or the ten evil acts and fall into hell than to have the mind of the two vehicles. Not falling into the evil paths might appear to be a considerable benefit, but the Buddha did not regard this as his true intention. Even if one should fall into hell, because one has heard the Lotus Sutra, which leads to Buddhahood, with this as the seed, one will invariably become a Buddha.

Thus, T’ien-t’ai and Miao-lo, following this principle, state in their commentaries that one should persist in preaching the Lotus Sutra. For instance, a person who stumbles and falls to the ground pushes himself up from the ground and rises to his feet again. In the same way, though persons [who slander the Lotus Sutra] may fall into hell, they will quickly rise up again and become Buddhas.

The people of today in any event already turn their backs on the Lotus Sutra, and because of that error they will undoubtedly fall into hell. Therefore, one should by all means persist in preaching the Lotus Sutra and causing them to hear it. Those who put their faith in it will surely attain Buddhahood, while those who slander it will establish a “poison-drum relationship” with it and will likewise attain Buddhahood.

In any event, the seeds of Buddhahood exist nowhere apart from the Lotus Sutra. If it were possible to attain Buddhahood through the provisional teachings, then why would the Buddha have said that one should insist on preaching the Lotus Sutra, and that both those who slander it and those who believe in it will benefit? Or why would he say, “We care nothing for our bodies or lives [but are anxious only for the unsurpassed way]”? Persons who have set their minds upon the way should clearly understand these matters."