When the right moment came, he jumped. As he fell, the folly of his haste occurred to him with merciless clearness, the vastness of what he had left undone.
Oh yes, the vastness of yellow wallpaper and decades of rearing narrow-eyed no-neck monsters (after the distasteful drudgery of each individual conception). Paul's experience in Manhattan has shown him that the life he wants to lead can be had only with money. What sudden epiphany has occurred to him, in mid-drop, to convince him otherwise!? Our narrator abandons her creature with less care than he buried his red carnation. It's not enough he die ... he must despair and die (R3, V, iii, 128).
The next two failings are aesthetic. Part of Cather's success in this story is presenting it as a case study, introducing the latest medicinal pathologizing of homosexuality in describing a person of Paul's "temperament". She shatters that picture-making mechanism when she jumps into his mind for the last seconds of his consciousness (she, who wasn't even sure—"perhaps"—that her subject had looked into the dark corner). This failure of course is more generally one of inconsistent authorial point-of-view, but more acute here because of her adopted "case study" narrative.
The third failing is also aesthetic and embarrassingly bald.
Then, because the picture-making mechanism was crushed, the disturbing visions flashed into black, and Paul dropped back into the immense design of things.
—"the immense design of things"? Oh Willa, give this ember burning in your tea-pot tempest a break! Where did she find that tail to pin on the donkey!? There's been no "design of things" in evidence, immense or minute, explicit or implicit, in this aborted case study. Cather has pulled out all stops and hoped to leave us on a swell.
“Paul’s Case” was originally published in Cather’s first short-story collection The Troll Garden, a few months before its appearance in McClure’s. For reasons of the merest editorial convenience a page-worth of material was omitted from the magazine. Out of respect for both her and for her character, I will read the story's end as
When the right moment came, he jumped. He felt something strike his chest, and that his body was being thrown swiftly through the air, immeasurably far and fast … and that his limbs were gently relaxed.