When There Is No Mind Consciousness, Does the Manas Have Awareness?

Some say: Since the manas is also a consciousness, it should be able to perceive external objects; so why is it that when a person is unconscious, there is not the slightest perception of external objects? The answer to this question is as follows: the absence of perception during unconsciousness is the mind consciousness no longer perceiving, while the manas still has perception. When the manas perceives, once the mind consciousness has ceased, it cannot know the manas's perception; even if the mind consciousness has not ceased, if it lacks the wisdom to cognize, it still cannot know the manas's perceptive function. This is because the knowing of the manas must be made known to the mind consciousness before sentient beings can know it. Sentient beings all take the knowing of the mind consciousness as their knowing; whatever the mind consciousness does not know, they regard as unknown.

However, the mind consciousness not knowing does not mean the manas does not know either. Therefore, when one is sleeping dreamlessly or is unconscious—that is, when the mind consciousness has disappeared—the manas's knowing cannot be transmitted to the mind consciousness, so the mind consciousness does not know; and when the mind consciousness does not know, sentient beings do not know. Even when the mind consciousness is functioning normally and has not disappeared, if it lacks wisdom, it still does not know the manas's knowing. When the mind consciousness lacks wisdom, it also does not know what kind of mental activity the manas is engaged in or what the manas has perceived. Therefore, whether the manas has the introspection of self-validating cognition (sva-saṃvitti-saṃvitti-bhāga) cannot be observed by the mind consciousness, and whether the manas knows of its own existence also cannot be observed by the mind consciousness. So when the mind consciousness cannot observe these things, one should not make judgments about how the manas is or is not.