Is the wind moving? Is the banner moving? Or is your mind moving?

The public case in the Platform Sutra where the Sixth Patriarch said, "It is not the wind that moves, not the flag that moves, but your own mind that moves." This public case involves the movement of the external marks—the wind and the flag—as well as the movement of the conscious mind, and moreover, not only 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 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 one knows all things.

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 wish 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 tranquility (praśama) the mind has. Yet amid all this movement of consciousnesses, the true mind, the eighth consciousness, remains utterly unmoved, always tranquil, silent and unmoving. 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 when the wind and flag are moving violently, one can surely find the true mind, the eighth consciousness, which never moves at all—though this depends on the person's merit and his meditative concentration and wisdom.

When the wind and flag move, the eighth consciousness does not move—this is said with respect to ordinary people who have not yet awakened to the Path. The eighth consciousness can also be said to move, because the eighth consciousness has never been idle; it is always transmitting consciousness-seeds and discerning the faculties, the body, and the material world. If the eighth consciousness did not function, there would be no production of inner object-aspects at all, and no production of the conscious mind; the conscious mind would 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 His thoughts within the dharmas of the six sense objects in the three realms' world, and that is why it is said that suchness is unmoved, that suchness is immovable (tathatā-acalita).