“The newest trend and the art scene are unnecessary distractions for a serious artist,” Agnes Martin stated in 1989, aged seventy-seven. She ought to have known, having seen the trends come and go, outliving and outperforming each of them. Embraced by admirers of Minimalism in New York during the '60s, she countered that her grids were Abstract Expressionist. Expressionist? What can a grid “express”? “Innocence,” she said. Now she's reached ninety in New Mexico, titling her works Little Children Playing with Love and the like. Minimalism and Expressionism have passed into history. Martin's art remains—quite innocent of that history.

The Menil Collection is celebrating Martin with a selection of works from the past ten years. Initially, many look remarkably similar; but once acclimated to the subtleties of Martin's methods, you see how satisfyingly varied this group actually is. In 1993 Martin moved into a new studio in Taos; given her advanced age, she decided to use a smaller format (five feet square instead of six feet square) so she could continue to handle her canvases without assistance. She likes solitude.

Uncannily, the Menil galleries look as if they'd been built for Martin's paintings alone: the parallel lines of dark floorboarding resonate with her horizontal bands, a fortunate coincidence; more important, the natural light, diffused through baffles, greatly enhances the atmospheric effect of her pale washes of color (mostly pinks, blues, yellows). One atmosphere, the outside light, encounters another atmosphere, Martin's weightless emanations of color. The situation is in flux, not only because the natural light changes, but because the calm of Martin's paintings is a sea calm—despite the pacific horizontality, something of the surface still moves. As you draw close, smoothness yields to irregularity. What you perceive is more incident than disturbance, like life's little realities, waves on boundless water. This is only partly a metaphor, for many of Martin's colored bands are fluid and indeed wavy. She turns her canvases to apply the washes vertically, letting the thin paint flow downward. A subtle asymmetry results, as the edge where the movement begins usually becomes more opaque than its counterpart at the other end.

Martin's coloristic atmosphere must be related to the studio light to the morning hours that she devotes to painting, yet she isn't imitating anything and doesn't follow nature. Light is her means, not her model; and it's a very liquid light. Perhaps this is why the Menil galleries seem as if they were constructed around Martin's paintings, as if they were containers, with the canvases slightly destabilized, drifting or floating within. Paradoxically, the paintings, with their internal divisions, constitute the full ocean, not a set of islands: “My paintings,” Martin says, “are light, lightness, about merging, about formlessness. . . .You wouldn't think of form by the ocean.”

Untitled No. 2, 1993 is the exception to prove the rule. Here, horizontal pencil lines in groups of three become the figure on a uniform, relatively opaque blue, which ought to appear as solid ground. But this applies only in the technical sense that the pencil lines lie above the paint layer. Visually or emotionally there's no such hierarchy, and this lack of logic or dominant pattern characterizes most of Martin's work. Accordingly, I was disappointed by a few paintings from 1999 and 2000, those having repeating clusters of five, seven, eight, or nine bands; they appeared more like pattern than like desert plain, ocean, or light, to invoke three of Martin's favored motifs.

Pattern, symmetry, and abstract geometry suggest an ideal perfection; but Martin violates her own evocations of order. She nevertheless thinks that life in the abstract is perfect—universal, selfless life, which is neither hers nor ours. “The work is about perfection as we are aware of it in our minds,” she insisted long ago; “the [actual] paintings are very far from being perfect.” Indeed, her straightest lines wobble and skip along the surface, sometimes razor thin, sometimes bumping the crests of the canvas weave. “A hint of perfection,” says Martin, “is enough to make a painting alive.” Wouldn't such a “hint” have to be imperfection itself, the flaw that lets you imagine flawlessness? Martin's horizontal bands can be so pale as to seem white; you may have to stare to cause them to reveal their faint blush. This kind of color, a lapse in pure whiteness, is an imperfection. Through it, you imagine the perfect “white” of light. This isn't the white of studio walls, but the “white” that animates color, as Martin's white gesso (more materially) animates the washes layered over it, sometimes texturing them. Such is the effect of Love and Goodness, 2000, where gesso ground and acrylic figure combine—like love and goodness.

Martin once wrote a quatrain, opposing oceanic selflessness to insular self-interest. She glimpses a sea of happiness from the perspective of human failing, where each individual can be no more than “the newest trend,” a passing swell in the greater tide: “The ocean is deathless / The islands rise and die / Quietly come, quietly go / A silent swaying breath.”

Breath, a pulse of life, links transient islands to eternal ocean in the way that Martin's colors connect to perfect light. Her paintings point to for those like her, already secure and centered enough to imagine it. For others, perhaps these paintings at least help to center. It is good to be alone with them.

Richard Shiff is Effie Marie Cain Regents Chair in Art and director of the Center for the Study of Modernism at the University of Texas, Austin.