The Three Faculties Across the Path

T1606 identifies exactly which faculties make up each of these three, and the underlying set turns out to be a single group of ten, simply relabeled at three different points along the path. The not-yet-known-will-know faculty consists of the mental faculty together with the five faculties of faith, diligence, recollection, concentration, and wisdom already examined earlier — plus, depending on the specific meditative level involved, one of the four faculties of pleasure, joy, distress, or equanimity. Distress specifically belongs here because, T1606 explains, a practitioner still on the path of preparation, having already left the mundane path behind but not yet directly realized the supramundane liberation being sought, can still feel a kind of anxious yearning for what has not yet been attained — a real feeling, but one confined entirely to this earliest stretch of the path. These same ten faculties, once the sixteenth mind-instant of the path of seeing has been reached and direct realization has actually occurred, continue on as the already-known faculty throughout the entire remaining path of the trainee, all the way up to the vajra-like concentration that marks its very end — called "already-known" because, from that first moment of realization onward, no object still needing to be known through this path remains yet unknown. And the fully-known faculty is simply the same set again, minus distress alone — since an arhat, having nothing left to be trained in, no longer feels this particular anxious yearning — now belonging entirely to the arhat and to those who share that same accomplishment.

This brief note answers a natural question about how cultivation actually spreads once real mastery has been reached: does progress made on a higher meditative level leave the wholesome roots of the levels already passed through simply behind, untouched from that point on? The treatise's answer is no. Because a practitioner resting on a higher level has already attained genuine mastery over every level beneath it, actual cultivation undertaken from that higher vantage automatically carries the lower levels' own wholesome roots forward as well — cultivating the first dhyāna, for instance, simultaneously strengthens the desire realm's own wholesome roots, and this same pattern repeats at every subsequent level all the way up. Mastery already achieved, on this account, is never left idle behind as cultivation advances; it continues doing active work in support of everything still being built on top of it.