Nine in the Fifth Place attains the honored position and dwells in centrality and correctness, fully embodying the goodness of the way of pleasing; yet the sage once again sets down the warning of danger.
Even in the flourishing of Yao and Shun, warnings were never absent; one simply warns where caution is due. Even when sages and worthies are above, petty persons never cease to exist under Heaven; yet they dare not unleash their wickedness.
The sage also rejoices that they can make an effort to reform their appearance. Those petty persons never fail to recognize that sages and worthies can be pleased; like the Four Evils in Yao's court, who concealed their malice and obeyed orders, this was the case.
It is not that the sage did not know they were ultimately wicked; he merely took advantage of their dread of punishment and forced benevolence.
If Five sincerely trusts the petty person's fake goodness as true goodness, failing to see what lies concealed, that is the road to danger. If preparations against petty persons are not thorough, they harm the good. The sage's intent in giving warning is profound.
Bō (Splitting Apart) is the name for the waning of yang, where yin strips away yang; it refers to Six at the Top, hence trusting in Splitting Apart brings danger. Because Five is in a time of pleasing and intimately adjacent to Six at the Top, the warning is given.
Even Shun's sagehood feared clever words and an insinuating appearance—how could one not take warning? Pleasing deludes people, entering easily and inspiring such dread.