Why Can Manas and Consciousness Communicate Intentions with Each Other?

For instance, when the manas (the thinking mind) desires to eat, the Tathāgatagarbha (Buddha-nature) complies with the manas’s intention, giving rise to consciousness. The manas then communicates to the consciousness to discern the various dishes before it, selecting among them the one it prefers to eat. The consciousness can comprehend the manas’s thoughts. After the consciousness discerns, the manas can also comprehend the consciousness’s thoughts; the two can communicate instantly with each other. However, when the manas discerns dharmas (phenomena) from past lives and communicates them to the consciousness, the consciousness is unable to comprehend them, or only understands a little. Why is this? Because the consciousness has not experienced past lives and thus has no memory of them, it cannot discern them.

The manas decides to discern the various dishes to determine which one to eat, and the consciousness arises to perform the discernment on behalf of the manas. After the consciousness discerns and judges the characteristics of all the dishes, it communicates this to the manas. Once the manas understands, it decides what to eat. It is also possible that the consciousness, relying solely on observation alongside the eye-consciousness, cannot discern everything comprehensively. Therefore, the manas decides to taste a little. Then, the tongue-consciousness and nose-consciousness join in to discern and judge. Once the manas understands, it knows which dish is tasty and to its liking, and thus begins eating heartily, ignoring the unpalatable ones.

These dishes can be directly contacted by the consciousness and the five sense-consciousnesses together, so there are feelings (vedanā), perceptions (saṃjñā), and volitions (cetanā), enabling judgment. Regarding dharmas from past lives, without supernatural powers, the five sense-consciousnesses cannot contact them at all. The consciousness lacks the psychic ability, has no experience, and insufficient wisdom, so it cannot know what the manas is thinking or intending. If the consciousness possesses great wisdom, it can clearly discern the dharmas thought, intended, or implied in the manas’s mind.

Why can the consciousness and the manas communicate their intentions to each other? Because the manas contacts the mental objects (dharmas), giving rise to consciousness. The three (manas, consciousness, and mental objects) then combine and contact. Regarding mental objects, not only can the manas discern them, but the consciousness can also discern them, differing only in the degree of discernment and clarity. Throughout this process, the consciousness and the manas are also constantly in contact, mind contacting mind. Naturally, they can mutually know each other's intentions, with the difference lying in the depth and scope of that knowing. As long as the consciousness exists, it is necessarily in contact with the manas. Therefore, their respective intentions can be transmitted and exchanged anytime, anywhere. If the exchange is poor, the mind will feel unsettled; if communication flows smoothly, the mind will feel pleased. This is somewhat analogous to the interpersonal relationship between two individuals.