The master function of the manas determines that the manas has the nature of good and evil.

The manas silently encompasses all dharmas, meaning that the manas corresponds to, accords with, merges with, and conditions all dharmas, including wholesome and unwholesome dharmas—this is quite easy to understand. If the manas did not correspond to wholesome and unwholesome dharmas, how could the mind consciousness correspond to wholesome and unwholesome dharmas? If there are dharmas that the manas does not correspond to and does not condition, how could the mind consciousness correspond to them or condition them?

From the perspective of the manas's actual functions, if the manas had only a neutral (avyākṛta) nature, then neutral karmic acts such as washing clothes and cooking would be decided by the manas, while doing good deeds and taking pleasure in helping others would not be decided by the manas, and stealing, robbing, and lying would likewise not be decided by the manas. That would mean the manas can only make decisions and choices regarding some dharmas, but cannot make decisions and choices regarding other dharmas. Then what causes the manas to be able to make decisions only about some dharmas but not about others? Are the dharmas that the manas cannot decide actually decided by the mind consciousness? Has the mind consciousness also become the deciding consciousness? Splitting the manas apart, splitting the dharmas apart—is there such a principle?

If a person is good, is it the manas that is good, the mind consciousness that is good, or are both good? If a person's goodness is only the goodness of the mind consciousness, and the manas is not good, then after the mind consciousness ceases, with only the manas remaining, is this person still a good person at that moment? If the manas is not good, then at that moment he is no longer a good person. If a good person, once asleep and without the mind consciousness, is no longer a good person, then how do we account for the good deeds he has done? Isn't this matter very bizarre? It is simply inconceivable and can never be explained.

According to this logic, after a good person dies, the mind consciousness of this life vanishes forever, and he even less can be a good person. Someone who did good deeds all his life, yet after death no one acknowledges him as a good person—isn't that unfair? If he died for the country or for the people, his death would not even be glorious, because the glorious mind consciousness is gone, so no glorious title can be posthumously conferred on him, and no spiritual or material compensation can be given to his family. If, along with the disappearance of a good person's mind consciousness, all the good deeds and contributions made by that mind consciousness also vanish, because the remaining manas is not good, then in the future good people might fear death the most and refuse to make sacrifices easily. They might also fear sleeping and falling into a coma, because once the mind consciousness ceases, the label and reputation of being a good person disappear, and after death they would not go to a wholesome destiny to enjoy blessings. Conversely, an evil person, once dead, is no longer an evil person and need not go to the three evil destinies—how worthwhile is doing evil? Such things truly cannot be explained. Therefore, the manas of a good person has a wholesome nature, the manas of an evil person has an unwholesome nature, or the manas of both good and evil people has both wholesome and unwholesome natures, which together with the neutral nature makes three natures.

If only the mind consciousness has wholesome and unwholesome qualities, and the manas has none, then when a good person acts in a play, portraying an evil person and doing evil deeds, is this actor at that moment a good person or an evil person? In work and in daily life, some people are especially good at disguising themselves—one face in public, another behind the scenes. On the surface they behave very well, like upright gentlemen, and their conduct compels praise; yet behind the scenes they scheme and plot to harm others. So is this person actually a good person or an evil person?

When sentient beings do good deeds or commit evil acts, it is a time when the manifest and the hidden operate together: the six consciousnesses are in the open, while the manas is behind the scenes in the dark. How do the two cooperate and connect seamlessly? On the surface it appears that the six consciousnesses are doing good or committing evil, but what is the manas doing? What mental activities is it engaged in? How is it operating? Does it exercise dominion over these wholesome and unwholesome matters, or does it let the mind consciousness decide and create wholesome and unwholesome karma? How does the manas cause the six consciousnesses to arise and operate? How does it cause the six consciousnesses to arise precisely upon the wholesome or unwholesome dharmas being engaged in? If these matters cannot be observed, how can one be certain that the manas has no wholesome or unwholesome mental activities and no wholesome or unwholesome nature?