Viktor Frankl spent three years in Nazi concentration camps, including Auschwitz and a subcamp of Dachau, and wrote Man's Search for Meaning in the months after his release, partly to explain how anyone survived that with a mind still intact. One scene from the book is easy to miss because it is so short, but it carries the whole argument. A line of exhausted prisoners was being marched back from a work site at dusk when someone noticed the sky over the Bavarian hills had turned violent colors, and a ripple went through the group as they stopped, mid-stride, to look. A fellow prisoner turned to the man next to him and said simply, "How beautiful the world could be!" These were men who had nothing, who did not know if they would eat that night or wake the next morning, and the sunset reached them anyway. Frankl's larger claim, the one the book is remembered for, follows directly from that moment: "Everything can be taken from a man but one thing: the last of the human freedoms — to choose one's attitude in any given set of circumstances, to choose one's own way."
What makes the scene worth returning to is not that beauty existed in the camp — plenty of true and terrible things existed there too — but that noticing it required no permission from the circumstances. The capacity to register what was good did not wait for conditions to improve. It ran alongside the suffering, on a separate track, available to anyone who still had the strength to lift their eyes. That is a strange kind of freedom, smaller than the freedom to change one's situation, but apparently the last one standing when everything else has been stripped away.
Seneca found a gentler version of the same discipline in an experience nowhere near as severe: getting old. In Letter 12 of his Letters to Lucilius, he describes visiting his old country estate and finding it in decline — walls crumbling, an outbuilding he does not recognize until his steward explains that he planted the trees around it himself, as a boy. The evidence of his own aging is suddenly everywhere, in the bricks and the branches, and for a moment the visit turns sour. Then he catches himself and reverses course. Old age, he decides, is "full of pleasure if one knows how to use it," and he reaches for an image from Epicurus to make the point: the days that please most are the ones nearest their end, the way the last sip of a drink, or the last bite of ripe fruit, carries a sweetness the earlier ones did not have, precisely because it will not come again.
Between them, a burning sky over a work camp and a sagging garden wall make roughly the same case: loss does not automatically cancel what is good in a moment, it just requires the mind to keep looking after most people would have stopped. The sunset was still there whether anyone watched it or not. The only real question was who still had it in them to lift their head.