To observe the mental activities and functions of the manas, as well as the mental factors, one must cultivate to the extent that both the consciousness and manas transform into wisdom, which at minimum corresponds to the stage of a First Ground Bodhisattva. The transformation of consciousness and manas into wisdom requires: First, the eradication of the view of self and the cessation of the arising of afflictions, attainment of meditative concentration at or above the first dhyāna, and becoming a noble one at or above the third fruition. Second, realizing the true mind's inherent nature through enlightenment, possessing profound prajñā wisdom, and attaining the discriminating wisdom of a Mahāyāna Bodhisattva. Third, passing the third barrier in Chan Buddhism, thereby realizing the non-abiding nirvāṇa. Fourth, possessing the wisdom of consciousness-only. Overall, this requires meditative concentration at or above the first dhyāna, along with profound liberating wisdom from both the Mahāyāna and Hīnayāna traditions.
These observations are conducted using consciousness to examine the manas. Eradicating the view of self involves enabling both manas and consciousness to eliminate this view. As long as one can observe and realize that the manas is also a dharma subject to cessation and impermanence, this suffices to eradicate the view of self, without needing to directly observe the particularly subtle mental activities and functions of the manas. Similarly, to eliminate the innate self-attachment of the manas, it is sufficient to enable the manas to realize that neither the self nor what belongs to the self exists within the five aggregates and eighteen elements, and to progressively eliminate afflictions within the first dhyāna. The arrogance, self-attachment, and other defilements of the manas will thereby be eradicated, enabling one to become a fourth-fruition Great Arhat, without needing to directly observe the functions and mental activities of the manas.
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