How do we know enlightenment? (Hennegen)

While we might expect a philosophical or religious text to present wisdom as the result of concerted effort and practice as the continued application of this wisdom, Dogen posits a more supple and elusive nature of knowing and practicing. We tend to think of wisdom as an accumulative process, one of applying information and experience toward some higher form of knowing, often done under the guidance of some sort of mentor. We imagine "enlightenment" entails some sort of "aha" moment, the realization achieved at the culmination of all of our converting information into knowledge into wisdom, as though we reach a final stage of enlightenment that we then maintain for the rest of our days.

This approach treats wisdom as though it can be broken down into constitutive steps that, were one to follow them closely, assure the ultimate achievement: enlightenment. But Dogen thwarts our tidy process-driven conceptualization of enlightenment and its relationship to the "enlightened one" or the one who attains enlightenment:

“Enlightenment is like the moon reflected on the water. The moon does not get wet, nor is the water broken. Although its light is wide and great, the moon is reflected even in a puddle an inch wide. The whole moon and the entire sky are reflected in dewdrops on the grass, or even in one drop of water.

Enlightenment does not divide you, just as the moon does not break the water. You cannot hinder enlightenment, just as a drop of water does not crush the moon in the sky. The depth of the drop is the height of the moon. Each reflection, however long or short its duration, manifests the vastness of the dewdrop, and realizes the limitlessness of the moonlight in the sky."

In this metaphor, man is the water, reflecting enlightenment. He is not divided by enlightenment nor is it something he can wield. It is not under his control or mastery. The moon doesn't get wet and the water is unbroken: enlightenment doesn't change by man's attainment, nor is man changed from a "before" into an "after" by means of enlightenment. Enlightenment is not a singular event, but a continuous reflection. The size of the man, his intellect, his standing (aka the size of the pool of water) does not determine the possibility of reflection, for even the smallest drop reflects the moon's light.

I am curious about the association of "duration" with reflection. Do we attain moments of reflection, but they are fleeting, changing, subject to disappear and return? If we extend the metaphor, perhaps a cloudy night obscures the moon, thus the pool of water reflects no light. What might these clouds be? Our own "knowing" intellect? Our desire to wield or master the light?

“Here is the place; here the way unfolds. The boundary of realization is not distinct, for the realization comes forth simultaneously with the full experience of buddha dharma. Do not suppose that what you attain becomes your knowledge and is grasped by your intellect. Although actualized immediately, what is inconceivable may not be apparent. Its emergence is beyond your knowledge.”

The compelling thing here is that it seems possible to be reflecting the light ("realization") without our conscious understanding, perhaps without even knowledge of the fact that we have "achieved." It is not a gradual process, but something that "comes forth simultaneously" and is "actualized immediately."

I suppose that the questions that remain for me here are: am I conflating "enlightenment" and "realization" when Dogen intends for them to be distinct? How do we understand enlightenment in terms of permanence or impermanence (how can it have a duration that may be short or long?) and how do we reconcile its duration with the immediacy and simultaneity of realization?

8.7.3