Collage looks easy, doesn't it? Just collect bits of colored paper and printed detritus, arrange them on a sturdy ground, apply paste, and quicker than you can say "recycling" you have art.
Well, not always. Banal collages, like junk sculpture, are quite easy to make, as many artists continue to demonstrate. Yet when you encounter a master of collage, you realize how wide is the gap between the mundane and the masterly, and how infrequently the sublime is achieved.
Kurt Schwitters (1887-1948) might be the most inventive, determined, and sensitive collagist ever. Certainly when you see the best of his compositions you can't think immediately of anyone better.
Picasso and Braque usually get credit for inventing the process of sticking bits of real-life materials to paintings, but Schwitters, as we see in an exhibition at the Princeton University Art Museum, developed collage to its ultimate state of refinement and expressiveness.
In doing so, he made a major contribution to modern art, yet he's not as known to the public as he deserves to be.
Perhaps this is because he worked in provincial Hanover, in his native Germany, rather than in Paris. Or perhaps it's because the Nazis hounded him out of Germany in 1937. He fled first to Norway, then eventually to Britain, where he died at 60.
The irony of Schwitters' career is that while he's remembered first for his collages, the focus of the Princeton show, he considered a complex sculptural environment he called Merzbau his most significant work.
He constructed one of these in each of the places he worked; the second and third versions were re-creations of the first, which Allied bombs destroyed in 1943.
In the early 1980s, a Swiss designer named Peter Bissegger re-created the central section of the Hanover Merzbau from photographs that Schwitters commissioned in 1933.
The re-creation stands as the exhibition centerpiece; while not precisely a replica, it evokes the essence of the artist's creative thinking, in which most of modernism's major currents, from cubism to dada, converged.
Organized by the Menil Collection in Houston to its usual high standard, the exhibition is modest in size - 78 collages, sculptures, and assemblages.
It's nowhere near as comprehensive as the last American museum show for Schwitters, at the Museum of Modern Art in 1985. But then its ambition is primarily to investigate how he used color, which means focusing on the collages.
Thank goodness for that, because while Schwitters was multitalented - a performer, writer, poet, and graphic designer as well as visual artist - the color-based collages are a special achievement. Encountering them in the exhibition's opening gallery, one instantly recognizes that Schwitters composed them with a painter's eye; he was, in fact, trained as a painter in art school.
It's clear from these examples from the 1920s, some no larger than a playing card or a postcard, that for Schwitters collage wasn't an alternative to painting or an accent within painting but a complementary process, a way of painting by other means.
These included a variety of discarded materials from daily life, such as bus and train tickets, claim checks, bits of packaging, and newspaper cuttings - typography was a key ingredient in his mix - that were quintessentially modern, as was the idea of transforming them into art.
Schwitters' earliest collages represent the purest form of modern art. They're rigorously abstract, lacking references to the natural world, narrative, figuration, topicality, or autobiography.
They insinuate significance through accumulation of detail and meticulous positioning of parts, generating a gravity disproportionate to their size.
Only the snippets of typography break the barrier between their self-containment and the everyday world, and even these aren't symbolic or referential but elements of design.
For the most part, Schwitters relied on interplay of shapes, often squares, and deft color juxtapositions to imply movement and space and create visual interest. With one notable exception, the early collages are precisely calibrated and persistently geometric; they evoke the structural logic of cubism without being purely cubistic.
The exception is Picture With Spatial Growths, which is messier and more random in its choice of materials, including a tuft of what looks like steel wool.
The later collages, particularly from the 1940s, are larger and a little less rectilinear, but the ones in this show also avoid representational images, such as photographs and illustrations.
Schwitters, who experimented with printing methods and printmaking, preferred text. This means his compositions have fewer familiar handholds; they can seem dry, even austere. Design, not symbolism or storytelling, delivers the message.
Like many artists of the modern period, Schwitters formulated a grandiose vision for his work; he aimed to integrate all known forms of art in a way that would define the intersection of art and life. He called this vision Merz, a word he borrowed from the German Kommerz (commerce). All his art became Merz, with Merzbau (Merz construction) being the culmination.
Merz, he said, "involved the selection, organization, and transformation of found materials, the new out of the old, art out of waste."
Schwitters' collages and painted wood reliefs exemplify Merz perfectly. The re-created Merzbau represents another aspect of Merz: If the artist doesn't find nature beautiful, he can manufacture his own.
Merzbau is an enfolding sculpture, a complex, nearly all-white grotto stuffed with vectors, curves, planes, and niches that evokes a constructivist daydream.
It's a treat to see this mythic construction, which some historians cite as the genesis of installation art, but ultimately it's not, like the collages, about generating art from refuse or recycling old into new. Merzbau is both puzzling and somewhat intimidating, while the collages, which can be just as mysterious, are beguiling and beautiful.
Since his death in England's Lake District on Jan. 8, 1948, Schwitters has become recognized as a prescient and significantly influential modernist. "Color and Collage" is a revelatory excursion to the heart of his invaluable legacy.
"Kurt Schwitters: Color and Collage" continues at the Princeton University Art Museum through June 26. The museum, in the center of campus, is open 10 a.m. to 5 p.m. Tuesdays, Wednesdays, Fridays, and Saturdays; 10 a.m. to 10 p.m. Thursdays; and 1 to 5 p.m. Sundays. Admission is free. Information: 609-258-3788 or http:// artmuseum.princeton.edu