Dharmas that the mind consciousness cannot observe are not nonexistent.

Entering meditative concentration through contemplation—in deep meditative concentration, on the surface it seems there are no thoughts, no thinking, no deliberation; yet in fact, although the mind consciousness has no thoughts or deliberations, the manas is still working and deliberating; it is just that the mind consciousness cannot observe this. What the mind consciousness does not know, the dharmas it cannot observe, does not mean they do not exist.

Therefore it is said that the manas has its unique function in the operation of all dharmas; that the mind consciousness cannot observe it does not mean the manas has no function. In investigating Chan, in meditative concentration, in sleep, in a coma—all the functions the manas performs, the operation of the mental factors of the manas—although the mind consciousness cannot observe them, this does not mean the manas has no function, nor does it mean the manas has ceased operating.

Some of us lack sufficient meditative concentration and wisdom; regarding the mental factors of the manas that we cannot understand or observe, we should not declare that they exist or do not exist, should not say yes or no; to remain silent and harbor doubt in the mind is what a wise person does.

The marvelous functions of the manas are extremely numerous, beyond our current thinking and imagination. Only if we do not cling stubbornly to shallow personal views and are not blocked by established, limited theories will it be possible in the future to observe more of the manas's functions.

In fact, the ultimate point of learning Buddhism and cultivating practice is to fully develop and observe all the functions of the manas and the eighth consciousness, and to fully realize them—then one becomes a Buddha. When all the dharmas of the manas and the eighth consciousness have been explored and realized, there is nothing left to cultivate, and one has reached the stage of being beyond training (aśaikṣa) in the Great Vehicle.

Regarding dharmas that one currently lacks the ability to observe and discern, one should not draw conclusions lightly; thus one does not create karma of slander and does not set up obstacles for one's own progress on the Path—this is the choice of a wise person. The Buddha often admonished bodhisattvas that they should hear the profound without fear, hear the profound without slandering it, and should remain patient and accepting toward the profound meaning of the Dharma.