Only when the manas has dharmas that it is mindful of does it deliberate and examine; first there is mindfulness, then deliberation and examination—without mindfulness, there is no deliberation. If the manas's mind is empty and does not dwell on anything, there is no mental activity, no need to examine or deliberate anything; at such times the manas is pure. However, when the manas has not been subdued, its clinging and engagement are relatively heavy, and the thoughts in the mind are extremely numerous, so the mind will constantly, endlessly deliberate, ponder, examine, judge, and weigh. If it cannot figure things out during the day, it continues examining and deliberating at night; in severe cases, one wakes up in the middle of the night and cannot fall asleep. This is why it is said that sentient beings' manas has the nature of continual scrutiny and deliberation. As for arhats whose manas has been subdued, there are almost no thoughts left in their minds; they hardly dwell on anything. Their manas only occasionally deliberates, but not constantly, so it is not called "continual." Therefore, as long as the manas deliberates on dharmas, there are thoughts; the dharmas being deliberated upon are the thoughts—the objects of mindfulness of the manas.
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