In Youthful Folly, Six at the Beginning represents the foolish youth, yet the line speaks from the perspective of enlightening folly. Nine at the Beginning of Yi likewise speaks from an external voice.
'You' (er) refers to Nine at the Beginning: 'You let go of your sacred tortoise and look at me with drooping jaws.'
'Me' is posited in contrast to 'you'; that which makes the Initial line droop its jaws is the Fourth line, yet it is not the Fourth line actually speaking, but a hypothetical phrasing. Nine is yang, firm, and bright; its talent and wisdom are sufficient to nourish rectitude.
It can swallow breath without eating; the sacred tortoise symbolizes its bright wisdom, capable of not seeking nourishment from without. Though its talent is such, occupying the moving trigram as yang during the time of Yi, seeking nourishment is human desire.
Corresponding above with Six in the Fourth Place, it cannot maintain its composure; its will strives to ascend, taking pleasure in desires and drooping its jaws. Once the heart is stirred, losing oneself is inevitable.
Bewitched by desire and losing oneself, following yin with yang, what extreme would it not reach? Hence it is ominous.
'Drooping the jaws' means twitching and lowering the jaws; moreover, when someone sees food and covets it, their jaws move and saliva drips, hence this image is used. The Image says: 'Looking at me with drooping jaws is likewise not worthy of respect.'
Nine belongs to the moving trigram; 'drooping the jaws' means it delights in yin and its will is stirred. Once stirred by desire, even though it possesses firm, vigorous, bright, and wise talent, it must ultimately lose itself; thus its talent is also not worthy of respect.
That humans prize firmness is because it can stand firm and not bend to desire; that they prize clarity is because it can illuminate and not lose rectitude. Once confused by desire and losing rectitude, what firmness or clarity remains? It becomes base and contemptible.