The Old in the Black Box

The black box matures gradually along with the progressive maturation of the physical body. The five external sense faculties, as one ages, continuously mature and then age, stiffen, and degenerate; the five supreme faculties (indriya) within the black box likewise gradually age and degenerate with increasing age. The seeds of the four great elements are constantly being renewed, and the functions of the five supreme faculties go from initial delicacy and frailty, to strength, and then to stiffness and degeneration. Among these, the transmitting nerves of the five faculties gradually become less sensitive, the four-great-element particles they transmit gradually diminish and become distorted and deformed, and the six consciousnesses become slow in discerning the inner six sense-objects (ṣaḍāyatana); their discrimination gradually becomes blurred and indistinct, and reactions become sluggish.

What the six consciousnesses discern about the condition of one's own body faculty is not the actual condition of one's original physical body, but rather the images formed within the black box of the supreme faculties from the original physical body—combinations of various particles such as electrons, atoms, neutrons, and so on. It is an illusory false body, not the original real, three-dimensional physical object. Therefore, there is no need at all to grasp at the physical body; these are merely combinations of bioelectric signals, with no body and no five gross sense faculties of the body faculty. If there were a real physical body, then there should not be the various superknowledges such as passing through mountains and entering water.