Does the Tathāgatagarbha’s Mental Factors Continue to Exist and Function in Parinirvāṇa?

If an Arhat can emerge from Nirvana without residue, it must be due to the maturation of certain karmic seeds. The Tathagatagarbha, relying on these karmic seeds, resumes functioning, giving rise to the manas (mental faculty). Then, the manas and the Tathagatagarbha together take rebirth, producing the five aggregates and the eighteen dhatus (sense realms). When karmic seeds mature, the Tathagatagarbha necessarily knows it; when karmic seeds are not mature, the Tathagatagarbha should also know it. So, what is this knowing of the Tathagatagarbha?

When the Tathagatagarbha functions based on karmic seeds, it is the operation of the mental factor of volition (cetanā). Before the volition operates, the mental factor of perception (saṃjñā) operates. Perception involves discerning and grasping characteristics—discerning the karmic seeds and grasping the characteristic of whether they are mature or not. Before perception is the mental factor of sensation (vedanā), which receives and experiences the karmic seeds. Before sensation is the mental factor of contact (sparśa) touching the karmic seeds. Before contact, there must be attention (manasikāra) directed towards the karmic seeds. Within Nirvana without residue, the Tathagatagarbha has nothing else to do; this is the only matter it attends to.

Moreover, for the Tathagatagarbha to operate this matter, it must have its own existence and continuous functioning to ensure the operation of this matter. The very existence of the Tathagatagarbha and its continuous functioning rely on the uninterrupted flow of its own seeds of consciousness. This continuous flow forms an unbroken stream of Tathagatagarbha consciousness. The five universal mental factors (pañca sarvatraga) accompany the Tathagatagarbha’s ceaseless operation. This is the meaning of the Tathagatagarbha being continuous and unbroken, neither arising nor ceasing.