The second half of this chapter and the whole of chapter twenty-four are the same four propositions, once in the positive and once in the negative, and the pairing is close enough that some readers treat them as a single unit split by the chapter divisions.
Here: he does not show himself and is therefore seen, does not consider himself right and is therefore distinguished, does not boast and therefore has merit, does not take pride and therefore lasts. There: one who shows himself is not seen, who thinks himself right is not distinguished, who boasts has no merit, who is proud does not last.
The four terms are identical and the order is identical. What differs is the frame. This chapter puts them under the sage who holds to the one and ends on the standing formula that because he does not contend, nobody in the world can contend with him. Chapter twenty-four puts them under two images of physical overreaching, standing on tiptoe and taking long strides, and ends by calling the behaviour leftover food and a tumour of an action.
The doubling tells you something about how the text was assembled. Repeated formulae, near duplicate passages and stock closing lines are what a collection of transmitted sayings looks like, not what a single continuous composition looks like. The final line of this chapter appears again almost word for word at the end of chapter sixty-six, in a completely different setting about rivers and valleys.
The chapter closes by defending the six opening clauses against the charge of being merely clever: what the ancients said about the bent being kept whole was not an empty phrase. That defensiveness is unusual and suggests the sayings were already old, and already being dismissed, when the chapter was put together.