It was the last nostalgia: that he
Should understand.

In these lines, “nostalgia” is treated not as a simple longing for the past but as a final, distilled yearning—something like the last remaining desire that persists when other attachments have fallen away. The phrasing “that he / Should understand” suggests a wish for comprehension rather than possession: the speaker (or an observing voice) frames understanding itself as the ultimate object of longing. The line break isolates “Should understand,” giving it the weight of a concluding aim or verdict. Read this way, the quote points to a late-stage, almost elegiac impulse: the mind’s last backward-looking hunger is to make sense of what has been lived, felt, or lost.