The First Moon, the Second Moon, and the Shadow Moon

In the Śūraṅgama Sūtra, the World-Honored One defines the second moon as the moon formed by pressing on the eye, which is more real than the reflected moon. The wondrous pure luminous mind spoken of in the Śūraṅgama Sūtra refers to the substance of the eighth consciousness, which is the first moon, the original moon. The functions arising from the substance of the eighth consciousness are the second moon, existing in dependence upon the substance. For example, the seeing nature—the Buddha-nature—by which the eighth consciousness sees all dharmas through the six faculties, is the second moon, not the function of the substance of the eighth consciousness. The operation of the mental factors (caittas) of the eighth consciousness—the function of discerning all dharmas—is the second moon, not the function of the substance of the eighth consciousness. The substance of the eighth consciousness, the first moon, cannot be seen by anyone, including the Buddha; one can only see the second moon and the reflected moon.

The reflected moon is all the illusory dharmas manifested by the eighth consciousness through the second moon, by employing karmic seeds and the seven intrinsically existing great seeds (earth, water, fire, wind, space, seeing, consciousness). This includes material form as well as mind, and mental factors.