"The only thing valid in art is the one thing that cannot be explained," said Georges Braque, the painter. He meant explained in words. One wonders what he would have thought of the two wordy photo shows now at the Corcoran Gallery of Art.

Both are well worth seeing. One sings, the other croaks.

Words and pictures often war as Georges Braque contended, but in "Time Pieces," Wright Morris' words and photographs are allies.

His prose-songs on the wall lend luster to his photographs. His photographs, in turn, put his paragraphs in focus. They spring from one clear vision, from one love, one intention. It is not the words alone, nor is it the photographs that give this show its fullness; it is the thought-fields between them. Morris' strictly composed photographs--of wood stoves, lace curtains, barber poles and barns--might well appear conventional were they not defended by his shining prose. And his words might seem mere fiction if the photographs beside them did not bind them to life.

Morris, born in 1910 in Central City, Neb., is famous as a writer--"Field of Vision," "Plains Song"--less so as a photographer. He made many of these pictures in and around Norfolk, a farm town in his home state, a quarter century ago.

One shows a tiny bedroom. A sagging double bed has been shoved against the wall. There is sunlight on the bed spread. This is what he writes:

There are hotel beds that give us the feeling of a negative exposed numberless times, then there are beds with multiple impressions of a single missing tenant. The bed is occupied when the sleeper is absent, the way the shoes on the floor are occupied by feet, and the house by a ghost.

The artist's words keep calling us back into his photographs. Before we sensed the ghost, we did not see the shoes tucked under the bed.

Another photograph shows old family portraits, perhaps on a dresser. Listen to the prose:

A straw-haired Scandinavian type woman, Opal Mason often cried when babies were born, girls especially, or when grown men slept with her. Something about the love-making of men struck her as sad . . . They were mostly good, decent, strong, silent, smelly men, and they all seemed to think they would live forever, make love forever, and then like babies drop off to sleep . . . In a railroad town she had the tooting engines, the smoking lanterns, the receding caboose lights, and the sleeping grown-up lovers all at one time. It made her sweetly melancholy. It was a great pleasure for her to lie there and cry.

There is one grand, looming precedent for these accurate, ecstatic picturings of rural life. It is "Let Us Now Praise Famous Men," the book by James Agee, with Walker Evans' photographs, that made the shacks and the hard life of Alabama's sharecroppers seem as noble and as timeless as these Nebraska farms. Both photographers show icons, and, though Morris would claim otherwise, both felt love at what they saw. Evans' vinegary photographs cut through the overripeness of Agee's heartfelt prose. Morris, whose photographs are sweeter, whose words are more austere, does the whole job himself.

"Counterparts: Form and Emotion in Photographs," Weston J. Naef's group show of forced photographic rhymes, supports Braque's contention that words and pictures clash. Naef's arguments and texts--some are obvious, others are nonsensical--heckle and embarrass the good pictures on the wall.

They come in twos and threes. Naef's show was organized by the Metropolitan Museum of Art, where he serves as curator of the department of prints and photographs.

"My purpose," he writes, "is to elongate Stieglitz's principle of equivalency to encompass paired photographs that may become formal and emotional equivalents of each other."

Sometimes his rhymes are strong. Maxime Du Camp's 1852 portrait of the "Colossus of Ramses II at Abu Simbel" and August Sander's German soldier (1945) clang together nicely. More often his "equivalents" seem a little dull. Another pair of pictures--one an Andre' Kerte'sz of 1948, the other a Hans Namuth of 1950--share a similar composition. Where floor meets wall in the Kerte'sz one sees an antique chaise longue; in the Namuth, where the floor meets wall, Jackson Pollock kneels, a paint can in his hand. What else, the viewer wonders, do these pictures share? Here is Naef's response: "In different ways, Kerte'sz and Namuth, directly or indirectly, consciously or unconsciously, before or after the fact, deal with destiny, death, birth, resurrection, and products of products." Huh?

When Naef claims to see a "very loud noise" in the "despair on the face of the gentleman in Lisette Model's photograph" (the gentleman in question is chewing on a sandwich), and then tries to compare that sound to "the quiet noise between the woman and child" in Robert Frank's fine portrait of his wife and son, we are comparably baffled. And irritated, too.

Naef has a good eye. And, of course, the search for harmony or dissonance in two quite different things--say a bread box and a basketball--is old and harmless fun: One is a rectangular, the other spherical. Right? And both are about this big! But Naef stretches too far. His show demeans its pictures. It often seems an exercise in curatorial imposition.

Naef tends to be a pedant. Wright Morris is a poet. What we learn from these exhibits is that words and pictures fight--unless the words and pictures are both works of art.

"Counterparts" closes May 8. The Wright Morris exhibition, organized by Washington photographer Mark Power, closes May 15.