I am writing about Constantin Brancusi on a machine with rounded corners. Chances are good that you own such a machine, too. Mine is mostly aluminum, but the surface has the faint roughness of ancient stone.

The aesthetic, which might be described as austere yet playful, seems right for an object that is both a serious, grownup device and a toy. At different times, it has symbolized human ingenuity, American pluck, sweatshop barbarism, the glorious future, and screen addiction. My point isn’t that Brancusi, the star of a euphoric retrospective at the Centre Pompidou in Paris, invented this aesthetic in his sculptures.

More than a hundred years ago, though, he perfected a kind of earthy sleekness that still looks embarrassingly , so fresh that it makes the actual present taste stale. Its peak, against strong competition, can be found in the sixteen svelte, polished, ridiculously cool versions of “Bird in Space” that he made between 1923 and 1940. Some are bronze, some are marble.

All could be tinted air. Their shape is something between a quill and a cobra, though maybe it’s better to say that they look the way flight feels, or the way flight should feel but never quite does. It has been almost thirty years since the last big Brancusi show—his works are so fragile and scattered that only the craftiest negotiations can bring them together.

“Brancusi,” curated by Ariane Coulondre, has managed a hundred and twenty sculptures, plus a slightly cheesy reconstruction of.