The Deliberation (manana) of the Manas Is Difficult to Observe

The deliberation (manana) of the mind consciousness is manifest and easy to observe, whereas the deliberation of the manas is hidden and not easy to observe. Because the mind consciousness has a relatively strong power of introspection, the solitary consciousness (mano-vijñāna-eka-citta) can observe some of the running modes of activity of both the mental consciousness accompanying the five sense consciousnesses (pañcavijñāna-sahagata-manovijñāna) and the solitary consciousness itself, but it cannot observe them all, because the mind consciousness has not yet achieved the transformation of consciousness into wisdom. The Buddha can observe them all, and the wisdom of the varieties of paths of bodhisattvas who have attained the bhūmis can observe most of them.

However, when the solitary consciousness is obscured by afflictions, lacks sufficient meditative concentration (samādhi), and has not transformed consciousness into wisdom, it cannot observe the running modes of activity of the manas. This is why it must be said that the deliberation of the manas is hidden. In fact, for the Buddha and for bodhisattvas who have transformed consciousness into wisdom, the modes of activity of the manas are still easy to observe. Whether hidden or manifest depends entirely on the observational wisdom of the mind consciousness, not on the manas itself.

The manas also has self-validating cognition (sva-saṃvitti-saṃvitti-bhāga) and possesses a weak power of introspection, capable of observing the manas' own modes of activity, but the manas cannot express them, so the mind consciousness (that is, what we call "we") does not know. Since the mind consciousness does not know the modes of activity of the manas, whether the manas' power of introspection is strong or weak, the mind consciousness still does not know.

Regarding things the mind consciousness does not know, many people's mind consciousness habitually denies them, saying they do not exist. Then, since the mind consciousness cannot observe the Earth's revolution around the sun and its rotation, one could also say the Earth is motionless. Saying so would cause no harm, but it would not accord with the facts. How many facts and truths can an ordinary person's mind consciousness actually observe? Not many—ignorance is too abundant and too thick, the obstructions too heavy. And precisely those with the most ignorance are the least willing to admit their own ignorance and the most trusting of their own judgments. This is truly helpless.