The wind moves? The flag moves? Or is it your mind that moves?

The public case in the Platform Sutra where the Sixth Patriarch said, "It is not the wind moving, not the flag moving, but your own mind moving." This public case involves the movement of the external appearances of the wind and the flag, and also the movement of the conscious mind; moreover, it involves more than these—it also involves the non-movement of the true mind, the eighth consciousness. Our deluded mind of the seven consciousnesses has clinging; when it attaches to the marks of sense objects, it can see the wind moving and the flag moving. As long as the six consciousnesses have seeing and feeling, they have moved; once the conscious mind moves, it perceives marks, and perceiving marks, it grasps at marks. When the six sense faculties contact the six sense objects, the eighth consciousness produces the six consciousnesses; when the six consciousnesses further contact the six sense objects, there is seeing, hearing, awareness, and knowing, and thus everything is known.

Therefore, where there is knowing, there is consciousness; where there is consciousness, it shows that the manas is clinging to the six sense objects, and all seven consciousnesses are moving. If the manas does not cling, it does not seek to contact sense objects, and the eighth consciousness will not produce consciousnesses to discern the six sense objects. The heavier the manas's attachment and clinging, the more the six consciousnesses discriminate, and the less tranquil the mind. Yet amid all this movement of consciousnesses, the true mind, the eighth consciousness, remains utterly unmoved, always tranquil, silent and still. Let the wind move however it will, let the flag move however it will—the true mind neither perceives nor knows, pays no heed at all, does not discriminate, does not give rise to thoughts, and is supremely tranquil. But precisely when the wind and flag are moving vigorously, one can find the fundamentally unmoving true mind, the eighth consciousness—though this depends on the person's merit and his samādhi and prajñā.

That the eighth consciousness does not move while the wind and flag move is said with respect to ordinary people who have not yet awakened to the Way. The eighth consciousness, however, can also be said to move, because the eighth consciousness is never idle; it is always transmitting the seeds of consciousness and discerning the faculties, the body, and the material world. If the eighth consciousness did not function, there would be no arising of the inner representation at all, and no arising of the conscious mind; the conscious mind would then not know that the wind and flag were moving. But the movement of the eighth consciousness is different from the movement of the mind of the seven consciousnesses: He never stirs a thought within the dharmas of the six sense objects in the realm of the three realms, and that is why it is said that suchness does not move—suchness is immovable.