Alfred Jensen: Dia Center for the Arts, New York.

Location, location, location: That was my mantra as I stumbled out of Dia's galleries and down those breakneck steps. No, I wasn't thinking about Chelsea real estate but about the Alfred Jensen problem. Where do we put him? Where does he put us?

But first, where did he come from? The biographical accounts are sketchy and do not always agree. Born in Guatemala in 1903, Jensen lost his mother at age seven and was sent to poor relatives in Denmark. At fourteen he went to sea. Two years later he jumped ship in San Francisco and set off on foot to his father's home in Guatemala--shades of Brancusi's legendary hike from Romania to Paris. By the time he got there his father had died, and Jensen established an ill-starred farm with his brother, about which he later wrote a Cain-meets-Abel short story featuring legions of tunneling scissor-mouthed ants. He fled to San Diego in 1924 to study art, then to Munich to enroll in Hans Hofmann's atelier, but not before ending up in a class with someone called Heymann because he'd forgotten Hofmann's name. ("It was an H man, but I didn't know who it was," he later explained.)

Sensing that German discipline was not what he needed, Jensen went to Paris and signed on with some mild old Fauves, who encouraged him to paint thick. He left the school with fellow student Saidie May, a young American collector who became his patron and more. After her death in 1951, he settled in New York and soon had a studio on Tenth Street and Mark Rothko as a friend.

In 1957 Jensen finally made his breakthrough. Leaving gesture behind, he became what he called a diagram painter. For his remaining twenty-four years he made big, labor-intensive paintings inspired by the Mayan calendrical system, Goethe's color theory, Faraday's electromagnetics, the precession of the equinoxes, the I Ching, Yuri Gagarin, you name it. If you want to figure it all out, there may still be handouts at Dia with Arabic-numeral equivalents for the Shang oracle-bone forms and Egyptian tally marks studding Jensen's work. Good luck.

So where does Jensen fit? Perhaps the best answer is in the '60s, the decade of his ascendancy. In 1963 Allan Kaprow wrote that the "contemporary vanguard looks to Alfred Jensen," and Donald Judd called him "one of the best painters in the United States." But what was being looked at? For Kaprow, it was Jensen's metaphysics in paint; for Judd it was that his paintings were "thoroughly flat."

This kind of contest between soul and body may have been echt '60s, as David Anfam suggests in his useful catalogue essay, but as Rosalind Krauss pointed out long ago, it is also the way modernists always fight over the grid. In her 1978 essay "Grids," Krauss put Jensen in the body camp because of his thick paint, but the fact that his grids rarely reflect the shape of the canvas the way that, say, Mondrian's 1919 "checkerboards" do lands him in the soul faction, his paintings having more to do with the projection of ideas than with the physicality of their support.

Yet Jensen insisted, to his great credit, that his revelational signs have what he called visual body, that they be effective to the eye. Hence all the nipply blobs of tube-squeezed paint, the palette knife slashings. We know he was inspired by Van Gogh's paint handling, but he also borrowed Stuart Davis's trick of laying in pigment with the precision of a fluoride treatment (not to mention that funky cursive script). Van Gogh and Davis excelled at putting the tactile in the service of the visual. So did Jensen.

Look at how the roughened texture of The Ten Thousand Things, 1972, creates an optical pincushion, or how the pretty gray and pink undergrid of Where the Gods Reside, Per I-Per IV, 1968, is allowed to peek through the not-quite-joined patches of surface impasto. Jensen's other virtues are his patterning, which can produce dazzling effects of drift tossed up by sheer number power, and his color, which Judd considered "very good." Jensen's color harmonies can be as surprising as in Ellsworth Kelly's early '50s work (see the center of Physical Optics, 1975, for example), partly because Jensen, on the basis of his reading of Goethe, boldly or foolishly included black and white in his spectrum. The effect is shocking, like seeing a rainbow on your checkerboard.

Still, I found myself liking two of the simplest, earliest works best, Parthenon and Mayan Temple, Per II: Palenque (both 1962), the smallest of the fourteen works in the show (indeed the only single canvases), the most thickly painted, and the only ones with some connection to visual reality, i.e., the architectural plans of their titular buildings. The balance between odd shapes and odd notations is pleasing. This is Jensen before the diagrams really rake over.

What happens when they do take over is that a modernist viewer like myself, still trying for some kind of unified capture of the visual field, gets swamped. It's no accident that Jensen's last major work, the thirty-foot-long Great Pyramid, 1980, seen here for the first time, refers to the same monuments that inspired Kant's mathematical sublime. Late Jensen makes us stunned counters, not beholders.

"It is as if he simply misunderstood what painting is," Peter Schjeldahl once wrote of Jensen. The misunderstanding, intentional or not, may be what has kept him hard to locate, but it is also what keeps him relevant. Today he seems in some ways closer to Mel Bochner, On Kawara, Hanne Darboven, Tatsuo Miyajima, and other scribes and accountants of our post-modernity than to Judd or Pollock or Davis. Of course, Jensen's goal was totally uncontemporary: a classic New York School search for correspondences, a hope to unite chronos and kairos, clock time and God time. It's too late for that, but at least we have the amazing colored excreta that his army of paint tubes left behind.

Harry Cooper is associate curator of modem art at the Fogg Art Museum, Harvard University Art Museums.