Why Is the Wisdom of the Mind Consciousness Greater Than the Wisdom of the Manas?

The wisdom of the mind consciousness is far greater than that of the manas. One reason is that the objects cognized by the mind consciousness are far fewer than those of the manas; He is not the master consciousness, and does not need to take charge of anything, so He does not have so many concerns and can easily focus on thinking through problems, and His discernment of states is relatively clear. The dharmas that the manas cognizes, concerns itself with, and discerns are numerous: whatever dharmas the tathāgatagarbha gives rise to, the manas can reach and cognize them; all matters related to oneself throughout past and present, and even the minute changes in the physical body at every instant, the manas can discern and know them all; even things unrelated to oneself, due to the habit of grasping, the manas will still grasp at and worry about them. Therefore the mind's thoughts cannot easily be concentrated, its discerning wisdom is weak, and its understanding of the Dharma is not clear.

Another reason the mind consciousness's wisdom is greater than that of the manas is that the mind consciousness exists for only one lifetime, is only very lightly influenced by environmental conditioning, does not have the manas's many afflictions and ignorance, nor so many karmic obstructions, and has fewer obscurations; therefore the mind consciousness is more intelligent than the manas.

If the manas cognized relatively few objects, if the ignorance in the mind were not very deep and heavy, and if over beginningless kalpas it had not accumulated boundless karmic obstructions of birth and death, then the manas would be as wise as the mind consciousness, and even with insufficient evidence it could still arrive at a reasonable conclusion, thereby realizing the truth. But the manas is not like this, and that is precisely why practice and realization are so difficult for us.