Hakuin Jenji's Zazen wasan says, "Open the gate of the oneness of cause and effect, don't think that these are two or three vehicles". ... Now in this "oneness of cause and effect," cause-and-effect means that there are differences of clarity and depth in enlightenment. In other words, it points to the fact that there are levels in practice-enlightnement. Oneness means that content of enlightenment is equal and without distinctions. In other words it points to the fact that there are no levels
. Concretely speaking, this means that although there are tremendous differences in the clarity and depth of realization depending on the maturity of a person's practice, the content of realization itself is always one and the same. Levels are no-levels, no-levels are levels.
This is the properly transmitted Zen of the buddhas and ancestors. In other words it is the properly transmitted Zen of Dogen Zenji. This is the meaning of the teaching that there is only one vehicle, not two or three. However, there is a tendancy for Rinzai Zen to present the Zen of levels on the surface with the Zen of no levels as its background, and for Soto Zen to present no-level Zen on the surface with the Zen of levels as its background. So then it seems that the Rinzai stream places emphasis on the Zen of levels and the Soto stream places emphasis on no-level Zen. Those who lack the dharma eye misperceive this. They think that Rinzai Zen is only
the Zen of levels and bad-mouth it, calling it stepladder enlightenment, or else they mistake Soto Zen to be only
no-level Zen that denies realization, and degrade Dogen Zenji's properly transmitted Buddha-dharma, taking it to be intellectual Zen, conceptual Zen, or explanatory Zen.