Buddhism is about to the wholeness and the interaction of our lives and the whole universe, which Dôgen describes as "rail of iron". This is the spiritual indivisible wholeness and not duality of subject and object. He used the same Japanese word for the dropping off of body and mind during the practice of zazen: the constricted meaning that we “have” or “own” the Buddha nature as an object has therefore to be dropped, in order to get to the encompassing entirety of real life.
direct interaction and not a division into subject and object. Dogen adds that this statement illuminates the living beings and the Buddha nature at the same time, so that it denotes the essential of our lives. Thus an objectifying, simple and insufficient understanding of the Buddha nature as a thing, object or substance is dissolved.