She is pale but fixed, and the one depicted corner of her mouth shows something gleeful, as if the subject is plotting or, indeed, achieving, at the very moment of depiction, a goal, a comeuppance, a sweet payback fervently sought. Is the joke that an unwed, unrich, quite smart, forward-looking piano enthusiast from the Middle West has just attained something so long wished for? It is an expression that might be termed “intellectual happiness”—that joy some feel must be a contradiction in terms but which, made flesh here, quite plainly is not. Here use and pleasure, practice and performance are joined at last and for all time. The distinguished thing, intact and, via clarion water-clear understatement, preserved, preserved.

The wide dark hat and a hastily rendered lace collar on a black black dress, all this could have only been done very fast, in speedy watercolor, by a genius of some sort, between other obligations, all at once, by accident. His accident, her plan.

At the Art Institute, this is the single watercolor in a room of six massive vertical oils. These others limn department-store heiresses and meat ladies. The oil portraits sometimes seem more intent on flattering the costly Worth dresses than ladies’ dashingly rendered local faces, their supplemental chins hastily euphemized but nonetheless suggested. One lady confronts us from alongside a Great Dane dog, obviously borrowed, and she holds a riding crop. But there’s an unfortunate assumption that she is about to hop sidesaddle onto the beast and whip it into service as an unwilling form of transportation. Just this April, I myself loitered in the echoing chamber of white marble. For forty minutes, I listened with feigned detachment as talkative gallery visitors discussed the museum’s cluster of its choicest Sargents. I swear that, a hundred-odd years after the picture was done and forty-some years after its subject’s death, the picture’s freshness still seems to grow.

After being overawed (even somewhat enjoyably snubbed) by the nine-foot oils, the more diligent lookers often come to rest before this, the smallest painting of the seven. I love to see viewers linger here longest. We find a woman vertical beyond an upturned steamer trunk, as if some household is in transit, and yet a still life has been improvised atop the trunk where one outstretched and elegant hand pivots. A wash of cobalt blue fills that hand with quick implied blood. What best distinguishes this picture from its mannequin companions is the way it presents a person plainly meditating on something, some fact or idea visibly satisfying. Simply put, it is a watercolor of a woman not handsome, not hideous, but shown, under her overhanging eave of a black hat, thinking something.