Drawn as a changing line, the opening nine of Nourishment tells a querent that something already in their possession is being neglected because a neighbour appears to hold better. The verdict is unusually blunt, misfortune with none of the conditional escapes other lines attach, and the reason is not scarcity. The stroke is strong and correctly placed at the base of the lower trigram Zhen, so the person in this position is not short of means. They have simply stopped counting the means they have.
The practical content sits in the comparison the image describes. Watching another set of jaws move is a measurement of oneself against somebody else, and the discarded tortoise stands for whatever the querent has quietly written off as inadequate because it does not resemble what is being consumed across the way. A reading landing here is usually asking about an opportunity, a skill, or a relationship that looks poor only beside a chosen rival. The counsel is to name that abandoned thing plainly and go back to it, not to acquire a better version of whatever is being envied.
When this line changes, the lower trigram Zhen becomes Kun and the figure becomes Splitting Apart, King Wen 23. The transformation makes the warning concrete. The one firm stroke that was the querent's own capacity is gone, and what remains is a structure being worn away from underneath. Envy in this reading does not merely fail to feed. It removes the solid thing that was standing under the person indulging it.