'How ya gonna keep 'em down on the farm after they've seen Paree?"

That was the musical question posed by a 1919 pop song immediately after the end of World War I. The truth is, of course, that we didn't keep them down on the farm. The song was, itself, an expression and an example of an American culture that was increasingly metropolitan, increasingly industrial, and increasingly shaped by interests that were far from the land.

The exhibition "Rural Modern: American Art Beyond the City," at the Brandywine River Museum of Art through Jan. 22, looks at how American artists between the world wars saw the farm, the fishing village, the pueblo, and the purple mountains' majesty after they'd seen Cézanne.

The premise of the exhibition is that although modernism is thought to have been a quintessentially urban phenomenon, many modern American artists, including some known for their depictions of the city, spent much of their careers painting nonurban settings.

This is an obvious, not particularly novel point. Georgia O'Keeffe, who did some wonderful paintings of New York, is, nevertheless, best known for her Southwestern landscapes. Her Barn with Snow (1934) in this show is a crisp abstract transformation of a New England cliché, and Lake George, Autumn (1922) is uncharacteristically luscious.

Many ambitious artists went to New York and became part of an emerging modernist scene. But many of them went home occasionally, or they went on vacation, or in some cases moved to rural locations once their careers were underway. The show includes many works they painted when they got there. Thus Charles Sheeler, a Philadelphia-born artist known for his precise, dynamic industrial landscapes, is represented here by two paintings, from 1925 and 1938, of the same staircase in Doylestown. The first seems to invent a kind of carpenter's cubism; the second recalls Charles Willson Peale.

The show also includes many other works that - it was assumed at the time - were made to be part of a different culture. These are by artists who weren't self-consciously modern or New York-based, though most often they were based in places like Dallas or Kansas City that can hardly be described as rural. Their ambition was to paint the American scene, to show what the country and its people looked like.

These regionalist painters were not oblivious to the previous half-century of art. They were more interested in showing what they saw than in how they saw. Still, their technique was often inflected with modernism. Thus, we think of Thomas Hart Benton as a hard-core antimodernist, yet The Cliffs (1921), a view of Martha's Vineyard, could almost be mistaken for an O'Keeffe because of its soft, undulating forms and a palette shaped as much by emotion as reality.

Such rounded, wind-shaped landforms appear repeatedly in this show, especially in the work of artists depicting soil erosion in the Dust Bowl era of the 1930s. Before this show, I had never connected such scenes of devastation with the streamlined automobiles and appliances introduced during the '30s to seduce consumers to buy into the future. Are the Dust Bowl paintings documents or artifacts of the visual style of their time? Probably a bit of both.

The innovation of this show, organized by Amanda C. Burden, associate curator at Brandywine, is to throw the out-of-town pictures of the New York modernists together with some of the regionalists' more modern-looking pictures and call it all rural modern. Interestingly, this same exhibition will be shown, with a larger selection of works, at Atlanta's High Museum of Art next year. There, the exhibition will be called "Cross Country: The Power of Place in American Art, 1915-1950," and it will be organized by geographical location, rather than, as it is at Brandywine, subject matter. What Brandywine is presenting as an examination of modernism the High Museum will show as regionalism. It's like two shows in one.

Despite its highly discursive labels, neither the Brandywine exhibition nor its catalog makes a convincing case that the notion of rural modernism increases our understanding of what happened to American art in the first half of the 20th century. Indeed, its greatest contribution may to be sow provocative questions.

Take, for instance, the weirdest work in the show, Wheat Field (circa 1943) by John Rogers Cox. Its bottom half is a rolling landscape of bright yellow grain; its top half is a dark-blue sky edging into black, dominated by a single bright white cloud that looks a bit like a halo - or cauliflower. In the distance, at the horizon line, is a symmetrical, gabled house. Is this surrealism or simply South Dakota?

Cox was trained in Philadelphia, taught for many years in Chicago, and was director of a museum in Indiana; he was no bumpkin. The mismatch between the vastness of the land and the small pretensions of our buildings is a recurring theme of this show. Cox adapted surrealist techniques to an essentially realist project.

In 1936, N.C. Wyeth and his son Andrew, then 19, painted the same church in rural Maine. The elder Wyeth was consciously experimenting with a looser painting style than he had used in the past; Andrew was his student. The paintings, though, are very different. The father's work is moody and dramatic, full of unsettled clouds, but the church rests comfortably on its hill. The son's painting is more abstract. The church is a series of planes, either bright white or in shadow. It is on the land, but not of it. The mood of the work is alienation.

As someone who grew up in New England, I believe Andrew Wyeth's view distills my experience of what such churches look like, while N.C. uses his modernist techniques melodramatically. To my eyes, Andrew's painting is both more realistic and more modern.

"Rural Modern" seems exquisitely timed, as the media seem to have rediscovered the phenomenon of rural America only during the last couple of weeks. And it contains paintings you will be happy to see, including some unfamiliar works by well-known artists, and interesting works by relatively obscure ones. But the show never quite makes the case that "rural modern" actually means anything.