What Use Is the Mind Consciousness to the Manas?

The mind consciousness, the five sense consciousnesses, and the five aggregates are all tools that the manas must use. Without these tools, the manas would be powerless in the world on its own; it needs the six consciousnesses and the five aggregates to serve it, making use of them to greedily grasp all dharmas in the world. Without the six consciousnesses and the five aggregates, the manas would be helpless.

Therefore, although the manas can know many dharmas, these dharmas must be processed by the mind consciousness. For example, suppose a ghost or spirit appears nearby. The manas feels it is quite frightening, fearing it might threaten itself, but it cannot deal with the ghost or spirit itself, nor can it evade it on its own. So, while the hairs stand on end, it alerts the mind consciousness to this matter. The mind consciousness is puzzled: What on earth is going on? Why do I feel afraid? Why does the surroundings feel eerie, as if something is about to happen? When the mind consciousness is sharp and thinks it over, it may come to know that there is a ghost or spirit nearby, and then it finds a way to avoid it. In this way, the manas achieves its purpose.

Therefore, although the manas has the capacity of knowing, matters still need to be handled by the mind consciousness and the five aggregates. After the manas realizes the Dharma, the pure bodily, verbal, and mental actions must be carried out by the mind consciousness and the five aggregates; thus the pure bodily, verbal, and mental actions of the six consciousnesses manifest the purity of the manas. However, after one cultivates to a considerably high level, having developed the four dhyānas and eight samādhis and possessed immeasurable supernatural powers and powers of the Path, the manas can substitute for the six consciousnesses. At that point, the six consciousnesses need not arise at all, and all matters are handled by the manas itself—extremely swift and convenient. Therefore, the function and status of the mind consciousness cannot compare with those of the manas; the relationship between the two is forever that of master and servant. The master needs the servant to take care of trivial affairs, but when the master's capabilities are great—everything fully modernized and automated—the servant is no longer needed, and the master can handle everything well and skillfully by itself.