What is Uninterrupted Mental Application?

"Interval" signifies separation and discontinuity, while "uninterrupted" signifies continuity without break or interruption. "Mental engagement" (manaskāra) refers to directing attention towards a dharma, inclining the mind towards it, and focusing upon it. Mental engagement is one of the five universally active mental factors (caitta) of the conscious mind. All eight consciousnesses possess mental engagement; each can incline towards a particular dharma and focus upon it.

Is the mental engagement of the eighth consciousness (ālaya-vijñāna) uninterrupted or intermittent? We know that all dharmas are produced and sustained by the eighth consciousness. Once the eighth consciousness ceases to engage with a particular dharma, it ceases to operate upon that dharma, ceases to produce seeds related to it, and consequently, that dharma must necessarily vanish and perish. Therefore, the continuous existence of any dharma necessitates the uninterrupted operation of the eighth consciousness's mental engagement. However, the existence of all dharmas arises firstly from the eighth consciousness spontaneously generating them based on ripened karmic seeds, and secondly from the mental engagement and clinging (abhiniveśa) of the manas (the seventh consciousness, or defiled mind). Therefore, at times, the mental engagement of the eighth consciousness is triggered by the mental engagement of the manas. Once the manas ceases its engagement, the eighth consciousness likewise ceases to produce and sustain certain dharmas, and those dharmas must necessarily disappear. Thus, the existence of certain dharmas must also involve the operation of the mental engagement factor of the manas. As long as a particular dharma continues to exist without interruption, the mental engagement factor of the manas must be operating continuously and uninterruptedly; otherwise, those dharmas would inevitably vanish.

Consequently, it is said that the mental engagement of the eighth consciousness can be uninterrupted, and the mental engagement of the manas can also be uninterrupted. Is uninterrupted mental engagement possible for the sixth consciousness (mano-vijñāna, the intellectual consciousness)? We know that the sixth consciousness is interrupted many times throughout the day; it invariably ceases involuntarily. Even if the sixth consciousness achieves uninterrupted mental engagement, it is only sustained for a period of time; it cannot maintain uninterrupted operation twenty-four hours a day. When the sixth consciousness engages uninterruptedly for a period, this is entirely due to the uninterrupted mental engagement of the manas. Once the manas ceases its engagement, the eighth consciousness ceases to project the seeds for the sixth consciousness, and the sixth consciousness must necessarily vanish in relation to that dharma.

Therefore, only under the condition of the manas's uninterrupted mental engagement can the sixth consciousness achieve uninterrupted mental engagement for a period of time. In reality, most of the time, the sixth consciousness becomes fatigued after engaging for a period, becomes scattered, and ceases; it cannot engage for excessively long durations. The mental engagement of the five sense consciousnesses is even more so like this. Without the mental engagement of the manas, and without the mental engagement of the eighth consciousness, the mental engagement of the six consciousnesses would not exist even for an instant. The six consciousnesses all depend on the eighth consciousness and the manas to manifest and operate; they cannot function independently, because they lack autonomy.

Once the manas forms uninterrupted mental engagement towards a particular dharma, it means it has been successfully imbued (vāsanā) by the sixth consciousness. It will then automatically and consciously direct the six consciousnesses to act according to the principles it has realized. The conduct of the mind (citta-caryā) will necessarily change, and physical, verbal, and mental actions will also necessarily change, without requiring further supervision or prompting from the sixth consciousness. Only when the manas has not been successfully imbued is it necessary for the sixth consciousness to constantly supervise, remind, and regulate it. This is because the manas lacks conscious awareness and has not been imbued or realized the dharma.