What Are Mind-Matter Separation and Mind-Mind Separation?

Once contemplative practice (vipaśyanā-caryā) gains strength, at first the mind and material objects separate, and then mind separates from mind. The separation of mind and matter is easy to understand and observe, but what is the state of mind separating from mind, and how can it be observed?

He Qianxing: I myself do not know whether mind has separated from mind; I suppose it has not yet completely separated. I only feel that the mind of fear has faded a great deal. In the past, I feared physical harm, feared the future, feared that my body would not be cared for. Now I feel that the body is a wooden tool; touching my body is like touching an external object, so there is no more fear. As for how to observe it: when the mind quiets down, the arising of mental thoughts is very obvious—arising and then vanishing, with the mind standing outside the thoughts, and the thoughts drift to and fro like dust. This disciple's level is still very low, so I do not even know how to describe it.

Assessment: Why was there fear in the past? Because there was worry. Why was there worry? Because of fear of losing and fear of not gaining—worrying over gains and losses. Why worry over gains and losses? Because the body and mind and the five aggregates (pañca-skandha) are taken as one's own, clinging to the gains and losses of the five-aggregate body and mind; when the mind cannot let go of itself, one will worry over gains and losses, and the mind will have worry and fear. When one's practice reaches the point of seeing the body and mind as empty and seeing the five aggregates as empty, there will be no more fear.

The separation of mind and matter is the mind leaping outside the body to objectively observe the physical body, just like observing a piece of wood unrelated to oneself—without emotion, not regarding the physical body as one's possession. At this point, one is not far from eradicating the view of self (satkāya-dṛṣṭi) regarding the body. The separation of mind from mind is likewise the mind leaping outside of itself, objectively and dispassionately observing the mind's various activities, various thoughts, various ideas, and various emotional fluctuations—wholesome, unwholesome, and neutral (avyākṛta) thoughts and emotions can all be observed, just as if observing someone else's. The conclusions drawn in this way are objective and truthful, impartial and upright. Thus one comes to understand the wholesome and unwholesome attributes of one's own thoughts, and will consciously or unconsciously correct and transform one's own mind. If mind has separated from mind, one is not far from seeing the Path.
These observations all belong to the contemplation of the four foundations of mindfulness. Regardless of whether a person has studied and practiced the four foundations of mindfulness, as long as they can observe truthfully, they will unknowingly enter into the contemplative practice of body, feeling, mind, and dharmas of the four foundations of mindfulness, and only afterward can they see the Path. The contemplation of the four foundations of mindfulness is the contemplative practice that must be cultivated before seeing the Path; therefore, the contemplative practice of any Hīnayāna dharma cannot be separated from the contemplation of the four foundations of mindfulness. The contemplation of the four foundations of mindfulness is the expedient method, the swift method, for reaching liberation, and it is also the expedient and swift dharma gate leading to the Mahāyāna.

Ru Chun: This disciple has observed that at certain times when afflictive habits arise, it is like using fire to ignite wet firewood—the flame flickers for a moment, but real fire cannot be kindled. Does this mean the mind has achieved a slight separation from the afflictions?

Assessment: Because the mind has seen the five-aggregate world as empty, the afflictions are no longer so many or so heavy. Like wet firewood encountering a spark—because water overcomes fire, the causes for kindling fire are incomplete, so fire cannot start; afflictive karmic formations naturally do not arise, and afflictive karma cannot be created. What is the cause for kindling fire? It is taking the five aggregates as real, as truly existent, as "mine." When one observes that the five aggregates are not self and not real, they have nothing to do with oneself—then what reason is there to kindle fire?

Ru Chun: It is indeed so. Without needing the mind consciousness to instruct it, the fire simply cannot be kindled, naturally and spontaneously. The state of mind is fairly stable and peaceful; it is just that sometimes a strong sense of renunciation suddenly arises, wishing one could immediately leave the present environment for a place isolated from the world, requiring no food or drink, no attendants, and free of all sorts of worries. I always want to find some place like deep mountains and old forests to stay alone in quiet purity. But wishing is one thing—reality does not permit it, so I can only stay honestly and helplessly at home, passing the days.