In December 2003, Mary Henry made her last painting. It has no title and is not up for sale at Howard House or at the Wright Exhibition Space, where Henry is now having what amounts to a retrospective exhibition of 44 paintings and preparatory drawings. She knew it was her last painting before she started it, and over tea in her Whidbey Island house, I ask what it felt like to paint it. I immediately regret the question. She thinks for a while, staring off. Her white hair is wavy and soft, her features sharp and petite. She is still beautiful.

Finally, she looks straight at me.

“You expect me to know that?”

Maybe she doesn’t want to return to the memory, or maybe she really doesn’t know. Her life, like her paintings, will not be distilled today. Still, there is the temptation to try. It reminds me of the late Kirk Varnedoe’s claim that abstract art requires faith, “a faith not that we will know something finally, but a faith in not knowing, a faith in our ignorance, a faith in our being confounded and dumbfounded, a faith fertile with possible meaning and growth.”

Henry turns 94 on March 19 and she has become a legend of Northwest art, a matriarch who has achieved her place by standing stubbornly still, facing one direction, until the turning world happened to pivot around and look at her. On this February day, I arrive to take her in, size her up. I come in part because there is no other woman holed up in a house on Whidbey Island, or anywhere else I know of, who has spent the last 45 years making hundreds of supersized, hard-edged, geometric, abstract paintings. Henry is an anomaly.

My other, secret reason for coming is that I have been puzzling over Henry’s paintings since I first saw her majestic, 12-foot-long diptych After Scarlatti (1990) at the Tacoma Art Museum in 2002. Henry’s paintings are alluring and unyielding, and I figure she’s the only way into them.

“Well,” she says. We are sitting at a scratched-up red table under a bright skylight, trying to figure out how to talk about 94 years. “Well,” I repeat loudly. She cannot hear very well lately. We laugh, then realize it wasn’t particularly funny, just awkward, and stop.

Next to the table is a drawing stand by a window. A tangled charcoal sketch dated September 2006 captures the overgrown trees outside, where Henry used to garden extensively. She tells me she’s not gardening anymore, and she’s not painting or even drawing. We sit here in the heart of an island, at the end of a series of forested back roads, at the end of a career.

What has been written about Henry’s work is peppered with references to other artists who make similar-looking work while ranging wildly in motivation and attitude. The Dutch painter Piet Mondrian was a spiritualist; Henry’s Yellow Squares (1965) at the Wright Space resembles his early pier series. El Lissitzky was a political propagandist; Henry’s stabbing diagonals and plump circles in the new mural at Howard House (sketched by Henry, executed by assistants) bring to mind his Bolshevik graphics. Henry’s own teacher in 1945, László Moholy-Nagy, was an adherent of the Bauhaus, the conviction that form can improve the world. A 1946 photograph by Henry of a complex wire sculpture she built looks like something Moholy-Nagy might have made, celebrating the intricate gorgeousness and possibility of the machine age.

The question of women in abstraction comes up, too. Seattle Times critic Matthew Kangas finds vaginal and breast references in her paintings; KUOW critic Gary Faigin compares her to Georgia O’Keeffe (these both cause her to make a pickle face and stick out her tongue, which she does every time she laughs, like a mischievous kid). A better analogy would be to Agnes Martin, the mysterious, dedicated woman born one year before Henry who lived remotely and alone, content to draw highly personal grids.

Geometric abstraction has been employed for so many reasons since the turn of the 20th century. Henry was driven to it, as if to an old flame, as a 50-year-old dutiful wife suddenly transformed into a freedom-loving hippie in Mendocino, California, in 1964. She’d been seduced by abstraction 20 years earlier.

She leads me through her compact kitchen out one of her front doors. She has two, equally plausible, front doors, which confuses everyone who visits (I sense she enjoys the guessing game). One door opens into her narrow kitchen, the other into a proper entryway. Henry doesn’t use the formal door, she takes the side route and slowly, walking with a cane but upright, ushers me across her driveway into her studio, a mossy shed next to the house with a modernist interior of bright white walls and a concrete floor.

This studio, packed with dozens of paintings, is a record of everything that has happened since the break of 1964, when Henry divorced her husband and reversed the course of her life.

As a young girl, she was talented at drawing and compelled to art, even making sketches as a toddler during World War I of wounded soldiers. But she had given all that up to raise two children, Suzanne (now a professor at Pacific Lutheran University) and William (who was killed in a car crash when he was 32 in 1981; Henry could not paint at all for a time after his death). Henry spent more than 10 years running the household by herself while working full time in commercial art, never getting to sign her name to her work or decide what to make. Her husband, Wilbur, an entomologist, was indifferent to her art, and when her children were grown, “I had to be free,” she says. “There was a point when I felt that if something didn’t happen, I would go crazy.”

The particular freedom epitomized by ’60s California hit her at first. (She still says “far out!” and her friend, the art photographer Richard Nicol, remembers her breaking into dance in her living room in the 1990s as she listened to Bob Dylan records.) She made paintings under the spell of the cosmic op art of the day, even a few in psychedelic Day-Glo.

But it wasn’t long before Henry came to her mature style: a strict focus on shapes and colors. Straight ahead upon entering her Whidbey Island studio happens to stand one of her final paintings, a canvas with its face to the wall bearing the backside inscription “December 8, 2003.” It is titled 0,10—most likely a sly reference by the then-90-year-old artist to an exhibition called 0,10 that took place in Petrograd in 1915 and changed the course of painting, laying the groundwork for every painting Henry has ever done.

At this exhibition, Russian artist Kasimir Malevich showed for the first time what would become his famous Black Square painting. It was nothing and everything, simply a black square on a white ground. He hung it in the corner of the room, where the main Christ icon would appear in a Russian Orthodox household, implying a new direction for art: Art would not stand in for something; it would be something. Painting was never the same.

Malevich was driven by the literary concept of zaum: the dream of a “transrational” language that would speak universally, purely. Black Square, zaum-like, was intended to communicate directly and without translation. Henry is a true believer that this is still possible today, and at least part of what feels like resistance in her work is the shock of plainness and the faith in clarity in a world reliant on contingency.

“I just paint the things I like or want to see, made visible to me,” she says. “It’s a matter of using my brain more than anything else because unless my brain is satisfied, I don’t want to finish.”

Henry spoke more expertly on the subject to the Oregonian in 1998, channeling zaum: “I believe the world is constructed on geometries. Everything is so beautifully put together. I’ve always wanted to create that feeling in my work, of getting down to the nitty-gritty and getting rid of all the things that aren’t important, to get to the essence of life. What do I hope people get from my work? Honesty. Simplicity. I wanted it to be uncomplicated and direct.”

To her friend Jim Wills, her work is classical in its approach. It looks at questions of perfection. And, yes, spirituality. “Mary’s like every Californian,” he says. “She’s secretly Buddhist.”

Her surfaces are perfectly smooth. She uses sable brushes that leave no texture behind, and doesn’t use tape to mark lines, which can leave paint ridges. Some of her straight lines are achieved with the help of T-squares or triangles, but she says she works freehand more often. She’s always had unerring precision: During World War II she joined the war effort by doing engineering drawings for Hewlett-Packard.

The shades of the colors and the overlapping shapes can imply a kind of tilting, rocking depth inside the picture that changes as the eye moves around the canvas—or they can lie as flat as an aerial view. The titles range from the romantic (Lost in Vermilion, 1996, a stunner at Howard House) to the bone-dry (Geometric Invention #3, 1990). Each painting is a certain kind of quest with its own rules and conditions.

I love the architectural works, and have a hunch Henry would have made a fine architect. In the center of El Albaicin (2000), referring to the old Moorish quarter of the city of Granada, is a haunting, simple shape like a dark hallway opening onto a distant room lit red. (According to her son-in-law, John Rahn, a composer at the University of Washington, Henry, in addition to being offered a job by Moholy-Nagy at his Bauhaus institute, also was offered entry to architecture school at MIT, but she turned down both for the same reason: to follow her husband’s job and keep the family together.)

We’ve spent 45 minutes perusing the stacks in her studio, and it’s getting cold. She comes upon a painting filed in among the rest, and declares, “This is my very last painting.” Like Malevich’s works, it is a series of circles and squares in solid colors. Wrapped in clear plastic and set on its side, it is hard to make out exactly, but it looks as precise and formal as ever, showing no sign of being a swan song, of being the last of its kind. Henry quickly directs my attention to another painting.