Evidence That the Manas Possesses Self-Validating Cognition (sva-saṃvitti-saṃvitti-bhāga)

First, the behavior of repentance and regret can prove that the manas possesses self-validating cognition (sva-saṃvitti-saṃvitti-bhāga). Repentance occurs because previously, when the manas lacked the wisdom to discern, it blindly trusted the mind consciousness's analysis and guidance and made a hasty decision. Later, the manas discovered that things were not as expected—the original decision had been made wrongly—and so a sense of regret arose in the mind. The manas discovering that the decision it made was wrong is precisely the function of the manas's self-validating cognition: after observing itself, it discovered its own erroneous decision.

Second, from the perspective of the transformation of the manas's mental activities, the manas possesses self-validating cognition. Through studying Buddhism and cultivating practice, and through the continual permeation by the mind consciousness, the manas gradually comes to recognize the truth, realizes its own former foolishness, makes a vow to correct itself, and embarks on the path to buddhahood. Continually raising one's self-understanding in the course of practice is the function of the manas's self-validating cognition; continually correcting oneself is the function of the manas's self-validating cognition; changing one's own mental activities and changing the mental factors (caittas) is the function of the manas's self-validating cognition.

If the manas lacked the power of introspection and lacked self-validating cognition, then the manas would be unable to correct itself. It is true that the manas relies on the permeation and guidance of the mind consciousness, but the one who ultimately recognizes the truth and changes itself must be the manas itself, not the mind consciousness. If the mind consciousness could change the manas, there would be no need to permeate and guide the manas—one could simply change it directly. The meaning of permeation is that the mind consciousness's ideas and views are accepted and agreed to by the manas, so that the manas also comes to hold the same ideas and views, and with these transformed ideas and views it makes correct decisions and actions; then the bodily, verbal, and mental actions are transformed.

The mind consciousness can only change itself; it cannot change the manas. If the manas does not want to change itself, it is impossible for the mind consciousness to forcibly change it. If the mind consciousness could forcibly change the manas, then studying Buddhism, cultivating practice, and even attaining buddhahood would be easy. But changing oneself must be an active behavior, not a passive one. Passivity may work for a moment but can never last forever; otherwise, anyone could be changed by the Buddhas and Bodhisattvas, escape the suffering of the six realms of saṃsāra, and embark on the path to buddhahood, and everyone would not be far from buddhahood. But the facts are not so. This principle can be understood through careful contemplation; it is not difficult to comprehend.