 Zen however thinks that the preceding is still a partial understanding of “here and now.” To fully understand it, it is helpful to examine the following often-quoted phrase, as it is particularly illustrative. Zen demands that the practitioner “show one’s original face before one’s parents were born.” This demand points to an experiential dimension prior to the bifurcation between the subject and the object—and hence “not two”—where “prior” means negation of the spatial-temporal ordering principles such as in Kant’s understanding of time and space as a priori forms of intuition. It points to a non-dualistic experiential dimension that is zero-time and zero-space, by which Zen means that neither time nor space is a delimiting condition for Zen-seeing. In zero-time there is no distinction between past, present, and future, or between “before” and “after”; in zero- space there is no distinction between the whole and its parts. One can also say that both time and space, experienced from the point-of-view of the everyday standpoint, is relativized when zero-time temporizes and zero-space spatializes, where zero time and zero space characterize the bottomless ground. Accordingly, Zen contends that zero-time and zero-space are the natural and primordial being of all things including human beings, for they are all grounded in it. Taking these points together, the Zen enlightenment experience suggests a leap from a causal temporal series. 