The functions and roles of the manas are inherently complete in itself.

Question: Can the manas provide delusive seeds to the mind consciousness? And apart from the mind consciousness, are the manas's functions and roles reduced?

Answer: The mind consciousness's delusions are indeed triggered by the manas; the content and direction of the delusions are provided by the manas and are regulated by the manas, manifesting the manas's wishes and intentions. However, these seeds, as well as all seeds, are still provided by the tathāgatagarbha. Only the tathāgatagarbha can store the seeds of consciousness and the seeds of dharmas used for deluded thinking; the manas cannot store any seeds, because it is not a substantial entity, because it arises, ceases, and changes, and because it cannot act freely or autonomously. If the manas could provide seeds, there would be two mind-essences capable of storing, and everything would fall into chaos. In reality, when the manas has formed a plan and made a decision to engage in deluded thinking, the tathāgatagarbha, knowing this, will cooperate by outputting the seeds needed for the delusion, including the seeds of the mind consciousness, and only then can the mind consciousness engage in deluded thinking. The manas only needs to first engage in deluded thinking and grasping, and this will bring about the appearance of the delusion; He is the driving force and source of deluded thinking. The ultimate source is still the tathāgatagarbha—all dharmas ultimately flow forth from within the tathāgatagarbha.

Apart from the mind consciousness, are the manas's functions and roles reduced? We should know that the manas has an extremely great many functions and roles. With regard to its functions and roles in relation to the six sense objects, if separated from the body of the five aggregates and the six consciousnesses, even if the manas had a thousand wishes and a thousand clever schemes, they would be difficult to display and difficult to exercise, because there would be no executor and no implementer, because there would be no subordinates and no hands or feet. Therefore, from this point of view, the manas is an indeterminate consciousness (avyākṛta): its wholesome and unwholesome mental actions cannot be realized, wholesome and unwholesome deeds cannot be committed, wholesome and unwholesome seeds cannot be stored, and wholesome and unwholesome karmic retribution cannot come to fruition. Therefore, before beginningless kalpas ago, before there were the inanimate world and bodies of the five aggregates, even though the manas had countless afflictive ignorances, it had no karmic actions of ignorance and affliction, and together with the tathāgatagarbha it dwelt in vast, unfathomable darkness. Therefore, apart from the mind consciousness, the manas still has just as many functions and roles; they simply cannot be displayed and cannot operate.