Which Consciousness Achieves Perfect Comprehension Independent of Mental Activities?

In the Śūraṅgama Sūtra, there is a statement: "Mahākāśyapa in this assembly has long extinguished his mental faculty, yet with perfect clarity he knows without relying on mental processes." Question: When it is said that Mahākāśyapa has long extinguished his mental faculty, which consciousness is being referred to as extinguished? And what does "extinguished" mean?

Answer: A person with the knowledge of others' minds can perceive the thoughts of others at any time and place, provided the other person has thoughts. If the other person is deep and thoughtless, or if they are in meditative concentration and do not casually give rise to thoughts, then their thoughts cannot be perceived, rendering the knowledge of others' minds useless. Which mind's thoughts are being referred to here?

The knowledge of others' minds perceives the mental processes of the conscious mind, because the mental processes of the conscious mind involve language, words, or sounds—including inner speech—thus giving form to the mental activities of consciousness, making them easier to discern. In contrast, the mental processes of the mental faculty lack language, words, or sounds; they have no distinct form and are not easily discerned. Discerning the mental activities of the mental faculty requires observing bodily, verbal, and mental actions—through the actions of the body and the workings of consciousness.

So, what did Mahākāśyapa extinguish when it is said he "long extinguished his mental faculty," enabling him to know with perfect clarity without relying on mental processes? Here, "mental processes" refers to those of the conscious mind. Mahākāśyapa’s perfect clarity of knowing did not come through the knowing of consciousness; it was the mental faculty directly knowing—perceiving both internal and external objects of the six dusts—directly replacing the knowing of the six consciousnesses. Therefore, what Mahākāśyapa extinguished was consciousness and the mental processes of consciousness, not the mental faculty itself. If the mental faculty were extinguished, Mahākāśyapa’s five aggregates would cease to exist, and he would have entered complete nirvana.