Josei Toda and SGI are those who suppose they have attained what they have not

"Deluded and shameless as the mind is, to declare that “the mind itself is the Buddha” is to be a person who supposes he has attained what he has not attained, who supposes he has understood what he has not understood, is it not?" -- Nichiren

Mind or even life itself [as asserted by Josei Toda and the SGI] is not the Buddha.