The Eighth Consciousness's Accordant Cooperation with the Sixth and Seventh Consciousnesses and Karmic Seeds

If the first six consciousnesses wish to discern the six sense objects, they are not active on their own; they are passive, directed and governed by the seventh consciousness, the manas. The six consciousnesses have a seeking nature with regard to the six sense objects, and whether they can find them depends on the conditions and causes. The eighth consciousness merely accords with the seventh consciousness, and in accordance with causes and conditions, in accordance with karmic seeds, manifests the six sense objects, allowing the six consciousnesses to discriminate, choose, and reject. First, the eighth consciousness delivers seeds of consciousness to the six consciousnesses so that they can become manifest. Whatever the seventh consciousness intends to do, the eighth consciousness accords with it—without choice, without conditions, without seeking any return—yet it must attend to the karmic seeds. No consciousness can control the eighth consciousness; the eighth consciousness has a nature of accordant compliance, with its own operating principles. However, after enlightenment, one can observe the eighth consciousness's nature of accordant compliance through various methods, to see whether He is obedient. Upon observation, one finds that indeed, no matter what you do, He accords and cooperates with everything, without the slightest resistance.

This is the realm of the aggregate of perception (saṃjñā), which is extremely illusory. For a detailed explanation, it has already been discussed in detail in the Tathāgatagarbha. It seems to be in the miscellaneous discussion chapter.