How can one prove that the manas has ceased to grasp at objects?

When the manas does not engage in grasping, the mind abides in samādhi. As long as there is meditative concentration, it indicates that the manas's grasping has weakened. From the second dhyāna and above, there is only the faint discernment of the mind consciousness, which shows that the manas grasps even less. The reduction or cessation of the mind consciousness's functions indicates that the manas no longer relies on the mind consciousness to discern mental sense-objects, and thus the manas has little grasping nature left. A concentration without the mind consciousness is the concentration of no-perception (asaṃjñi-samāpatti); when the mental factors and functions of the mind consciousness are reduced, it is the concentration of neither-perception-nor-non-perception (naivasaṃjñānāsaṃjñā-samāpatti); and when the manas has reduced even its own mental factors and functions, it is the cessation of perception and feeling (nirodha-samāpatti). When the manas has completely and thoroughly ceased all grasping, one will enter nirvāṇa without remainder (anupadhiśeṣa-nirvāṇa).