The Five Stages of the Yogic Ground

T1606 explains why "support" is the right name for the first stage: extensive learning about the four noble truths, gathered by a practitioner who has already built up the necessary provisions for awakening, is what all the subsequent stages of concentration will be built upon and supported by — hence the name. The second stage, application, is simply the correct, deliberate mental attention that then takes what has been learned as its own working object, thinking it through without distortion. The third stage, mirror, is called this because the concentration reached at this point, though it still bears a sign — meaning it still carries a mental image of its object rather than the object's own bare, unmediated nature — is nonetheless capable of clearly reflecting back what is being examined, the way a mirror reflects an image without itself being the thing reflected.

T1606 walks through this verse as a literal step-by-step meditation instruction, matching each line to a specific stage of insight. A bodhisattva seated in meditative concentration first observes the image appearing within that concentration and recognizes it as nothing other than mind itself, dependent entirely on that mind rather than existing as some external object being separately perceived. Once the very notion that this image corresponds to a real external object has thereby dissolved, the practitioner examines closely and finds only one's own thought remaining — the image was never anything but a projection of mind all along. Dwelling with the mind fixed on this recognition, one first comes to know that the grasped object simply does not exist. Since grasping and what is grasped are correlative — there being no grasper without something grasped — one next comes to know that the grasping subject is equally absent. And once both the grasped object and the grasping subject have in this way fallen away together, what remains is direct contact with utter non-attainment itself: a mind no longer divided into a knower standing over against a known.

T1606 notes that this five-stage ground is best understood as explained through two distinct halves: the first four stages — support, application, mirror, and illumination — explain the ground's own cause, the successive cultivation that actually produces it, while this fifth and final stage, basis, explains the ground's own fruit, the transformation of basis already examined at length in the treatise's account of the culminating path. What began, at the first stage, as ordinary extensive learning about the noble truths thus culminates, by the fifth, in the very same permanent removal of coarse heaviness and attainment of a purified basis that marks the path's own completion — the whole sequence forming a single continuous arc from hearing the Dharma to being transformed by it entirely.