Why can the manas and the mind consciousness communicate intentions to each other?

For example, when the manas wants to eat something, the tathāgatagarbha complies with the manas's wish and gives rise to the mind consciousness; the manas then conveys to the mind consciousness the task of discerning the various dishes before it, and among these dishes to choose the ones it likes to eat. The mind consciousness can grasp the manas's intent, and after the mind consciousness has discerned them, the manas can likewise grasp the mind consciousness's intent; the two can communicate with each other in an instant. However, when the manas discerns dharmas from past lives and conveys them to the mind consciousness, the mind consciousness cannot grasp them, or only understands a tiny bit. Why is this? Because there has been no experience of past lives, there are no memories of them, and thus they cannot be discerned.

When the manas decides to discern the various dishes in order to determine which one to eat, once the mind consciousness arises it discerns on behalf of the manas. After the mind consciousness has discerned and judged the special features of each of the various dishes, it conveys this to the manas, and once the manas is informed, it decides what to eat. It is also possible that the mind consciousness, relying solely on observation together with the eye consciousness, cannot discern everything comprehensively, so the manas decides to eat a little and taste it, whereupon the tongue consciousness and nose consciousness join in the discernment and judgment. Once the manas is informed, it knows which dish is delicious and to its own liking, and so it eats heartily, while not touching the dishes that do not taste good.

These dishes can be contacted presently by the mind consciousness together with the five sense consciousnesses, and so there is feeling, perception, and volition, and judgment can be made. As for the dharmas of past lives, without supernormal powers the five sense consciousnesses simply cannot contact them at all; the mind consciousness lacks the power of knowing others' minds, and also lacks experience and insufficient wisdom, so it cannot know what the manas is thinking in its mind. If the mind consciousness possesses great wisdom, it can clearly discern the dharmas that the manas is thinking of, contemplating, and hinting at in its mind.

Why can the mind consciousness and the manas convey their intentions to each other? Because the manas contacts the mental sense-objects and gives rise to the mind consciousness, and then the three together engage in combined contact. Regarding the mental sense-objects, not only can the manas discern them, the mind consciousness can also discern them; it is only a matter of the degree of discernment and whether it is clear. And throughout this process, the mind consciousness and the manas are also constantly in contact with each other; when mind contacts mind, of course each can come to know the other's intentions. It is only a matter of the degree of knowing, which differs in depth and scope. As long as the mind consciousness exists, it is necessarily in contact with the manas, so their respective intentions can be conveyed and exchanged anytime and anywhere. When the exchange goes poorly, the mind becomes sulky and at odds; when the exchange flows smoothly, the mood is pleasant. This is somewhat similar to the relationship between two people interacting with each other.