Is the Activity of the Manas in the Brain or in the Void Outside the Brain?

If the manas were outside the brain, it would have nothing to do with oneself; and if the manas could be in empty space, whose manas would that be? Who would execute the results of its deliberation (manasikāra/manana)? How could the faculties and sense-objects come into contact to give rise to the six consciousnesses, so as to feed back the manas's deliberation? Therefore it is said that the manas cannot possibly be in the empty space outside the brain. What lies outside the brain? Must it necessarily be empty space? The Śūraṅgama Sūtra says: 虚空生汝心内，如片云点太清里。This mind, of course, refers to the tathāgatagarbha, but does the manas also, following the tathāgatagarbha, cognize empty space? Then is empty space inside or outside the manas? Or is the manas inside or outside empty space? The manas silently encompasses and cognizes all dharmas, and is not confined or obstructed within the material body; the dharmas of the ten directions and three periods of time can all be cognized through the tathāgatagarbha. From this, one can see: how large, in the end, is our mind? It encompasses the great void.

The manas is also a conscious mind. The conscious mind does not operate inside the material body, outside it, or in between, because the conscious mind is formless and without mark; one cannot say that the conscious mind is inside the material body or outside it. And the manas, this conscious mind, can govern all dharmas inside and outside the material body, operating together with the tathāgatagarbha. Wherever the tathāgatagarbha is, the manas is certainly there following it. The tathāgatagarbha cannot operate any dharma on its own—except for the underlying realm of reality itself. Where the manas is absent, there is no phenomenon of life. If the manas were no longer in the brain, not only would the brain cease to function, the entire material body would cease to function, and life would no longer exist. The dharmas that the body of the five aggregates (pañca-skandha) can come into contact with are all operated by the tathāgatagarbha, and all have the manas following along; the manas, relying on the tathāgatagarbha, can cognize them all. And the dharmas that the body of the five aggregates cannot come into contact with are likewise operated by the tathāgatagarbha, and likewise have the manas following along; the manas can equally cognize and apprehend these dharmas.

For example, if someone practices recollection of the Buddha (buddhānusmṛti) and attains meditative absorption (samādhi), and truly aspires to be reborn in the land of bliss (sukhāvatī), then a lotus flower will appear for him in the lotus pond of the land of bliss. This lotus flower is not merely manifested by his tathāgatagarbha; rather, it is built in the lotus pond of the land of bliss by the tathāgatagarbha following the manas that has made the vow of rebirth there. So does the manas operate inside the brain or outside it? At this moment, the manas is neither apart from the brain nor apart from the material body, and yet is also in the land of bliss. If one says the manas can only operate inside the brain, then what about the lotus flower in the land of bliss? To whom does it belong? The mind-made bodies (manomaya-kāya) of all the great bodhisattvas are all governed by a single manas—are the manas of their various emanation-bodies inside the material body or outside it?

Take another example: when the eye consciousness sees ten people in front of it, upon which person's physical form is the eye consciousness actually contacting? Since it sees all ten people simultaneously, the eye consciousness has simultaneously contacted the physical forms of all ten people; it is not the case that it can only contact one person and not contact the others at the same time. The manas is likewise: relying on the tathāgatagarbha, it can simultaneously contact all the dharmas held and sustained by the tathāgatagarbha, without distinguishing inside, outside, or in between. Inside and outside the supreme faculty (indriya) there are the same dharmas; inside and outside the brain there are the same dharmas, and the manas can take them all as its object and deliberate upon them all. But the actual situation is that sentient beings who possess a supreme faculty, no matter where they go, cannot run beyond their own supreme faculty; even if they run to the edge of the sky, they still cannot get out of the supreme faculty. The manas's constant, attentive deliberation is upon all dharmas: it deliberates not only on the dharmas within the supreme faculty, but also on the dharmas outside the supreme faculty. He not only grasps at the body, but also grasps at dharmas—and this grasping is the hardest to deal with. The grasping attachments of the mundane world of the three realms—we are still unable to free ourselves from them even now; all of our thinking is constrained, because our insight is limited.