The birth of any dharma requires the manas as a condition

The manas pervasively conditions all twelve āyatanas and eighteen dhātus; the arising of any dharma requires the manas as a condition. Without the manas as a condition, the tathāgatagarbha cannot directly give rise to any dharma—the manas itself excepted. The six faculties include the eye faculty, ear faculty, nose faculty, tongue faculty, and body faculty; without the condition of the manas, these five faculties simply cannot arise. The six sense objects include form, sound, smell, taste, touch, and dharma; without the manas as a condition, the tathāgatagarbha simply cannot give rise to them.

How were the body faculty and the other five faculties initially brought forth? Only when the manas entered the womb together with the tathāgatagarbha were the five faculties produced. After birth, regarding any situation of the five faculties, the manas knows it all by means of the tathāgatagarbha. If a situation is somewhat unusual or severe and the manas cannot handle it, then the six consciousnesses will be produced to discern and deal with it. If it is unimportant and ordinary, the six consciousnesses will not be produced—it is enough for the manas to know it by itself. The same applies to the six sense objects of form, sound, smell, taste, touch, and dharma: the manas can contact them all through the tathāgatagarbha. Only if it wishes to discern and deal with them will the six consciousnesses be produced; if fine-grained discernment and processing are not needed, no six consciousnesses arise, and the six consciousnesses do not know the sense objects.

Unexpected situations lie outside of the mind consciousness: karmic power arrives too quickly for the six consciousnesses to be produced for discernment, and even though the manas knows what is happening, it is of no use—He cannot handle anything. The Śūraṅgama Sūtra says: 意根默容一切法. The scope of all these dharmas is fixed, without exception.