HANOVER, NH.- If artistic stature worked by osmosis, Christian Wolff could claim greatness based on that alone. “My father met Brahms,” he said, easing into conversation at a sturdy wooden table in the dining room of his home in Hanover. That meeting was in 1896, when Johannes Brahms was in Bonn, Germany, for Clara Schumann’s funeral. Wolff’s father was 6 or 7.

Wolff’s grandfather, a violinist, conductor and professor, knew Brahms personally and professionally, he said. His great-grandfather, also a conductor, was a supporter of Robert Schumann. “And my great-great-grandfather was a champion of Beethoven’s, so there is something back there,” he added, laughing at the implications of such a heritage.

Wolff, who turns 90 on Friday, is associated with a different pantheon. He is the last living representative of what’s known as the New York School of composition, a group that included John Cage, Morton Feldman, Earle Brown and David Tudor. Their tightknit circle shifted midcentury American music away from classic European models. And it radiated out, intersecting with other arts and artists who were making New York a leading center of modernism: choreographer Merce Cunningham, poet John Ashbery, painters Jasper Johns and Robert Rauschenberg, and many others.

Wolff lived in New York City for just under 20 years. Even so, he retains historical and aesthetic ties to it. Accordingly, he’ll be in town this weekend for a series of events celebrating his birthday at Judson Memorial Church in Manhattan’s Greenwich Village. On March 9, a multigenerational group of friends and acolytes will present works spanning his career, including a new piece Wolff composed for the occasion.

The location is auspicious. Judson Memorial Church, a hotbed of experimental art and dance in the 1950s and ’60s, is just blocks away from the site of the Washington Square tenement where Wolff’s family settled after fleeing wartime Europe. It was there that his parents, Kurt and Helen Wolff, established Pantheon Books, which published Carl Jung, Joseph Campbell and Paul Valéry, as well as the first English translation of the “I Ching.”

At the time, Wolff was more attuned to the classical repertoire favored by fellow émigrés like violinist Adolf Busch and pianist Rudolf Serkin, both family friends.

“I was, in fact, quite obnoxious about new music,” he said. But that changed thanks to his piano teacher, Grete Sultan, a prominent soloist whose repertoire embraced contemporary music. Determining that he wasn’t suited to a career as a pianist, Wolff began to create his own works. When he asked Sultan to recommend a teacher, she sent him to Cage, who lived farther downtown.

“When I introduced myself by name, he said, ‘It’s a good name for a composer’ — and then he offered me a cigarette,” Wolff said. “I was 16, I don’t smoke. He says, ‘How can you be a composer and not smoke?’”

Although he was Cage’s junior by more than 20 years, Wolff exerted an influence on his teacher, not least by presenting him with the “I Ching” translation, a book that would prove decisive in Cage’s search for a method to guide chance operations. In a letter of recommendation to Dartmouth in 1969, Cage wrote of Wolff, “He is not known as a student of mine for the reason that I learned more from him than he from me.”

Feldman also acknowledged his younger colleague’s innovations: “Christian Wolff’s early music, his development, the suggestions in all his work, have continually haunted my thinking,” Feldman wrote in 1964.

After an early period involving intense reduction of musical materials, like the proto-minimalist “Duo for Violins” (1950), Wolff sought to create structures that cultivated chance, and also required performers to pay close attention to one another, listening for aural cues to proceed. Or, conversely, to play similar material independently, in tandem. Increasingly, his goal was to allow players of differing abilities to work together.

Over the years, Wolff explored a variety of strategies: graphic scores, text pieces, geometric configurations in which clusters of standard notation hung suspended in expanses of white space. The results could be agitated, evanescent or surprisingly direct and tuneful. During the 1970s, sparked by the Vietnam War, he wrote overtly political works based on folk music and labor anthems, striking a middle ground between poles established by two friends: Frederic Rzewski’s virtuosic “The People United Will Never Be Defeated!” and Cornelius Cardew’s populist agitprop songs.

Regarding that phase, Wolff offered two observations: “One, it’s for the converted. That’s not even an issue. It’s a solidarity thing. The other side of it is pedagogical.” He cited “Wobbly Music,” a 1976 choral work whose title nods to the Industrial Workers of the World, a labor union founded in Chicago in 1905 and nicknamed the Wobblies.

“Most people had never heard of who the Wobblies were, and that’s one of the most important political movements in United States history,” he said. “So that’s just a matter of reviving people’s awareness — or making them aware that there is a history of left-wing resistance to the status quo — and that’s part of the American tradition.”

You could argue that all of Wolff’s music, in requiring performers to make considered, mutually respectful decisions, is political. Robyn Schulkowsky, a percussionist who has worked extensively with Wolff, suggests as much in “Wolff on Composition,” a 2022 documentary directed by Ernesto Livon-Grosman.

“What’s the music doing now, and does it need me?” Schulkowsky asks. “Does it need me to be quiet, or does it need me to participate? It’s that open invitation all the time, so it’s hugely political, I would say, listening today.”

Beyond his work as a composer, and informing it too, Wolff remained active as a performer, playing in a wide variety of settings over the decades, from a longtime association with the Merce Cunningham Dance Company to a surprising album with Sonic Youth. Unlike Cage, he embraced improvisation, performing as an adjunct member of the English ensemble AMM. Even now, he continues to embrace spontaneous collaborations — and will do so during his birthday concert.

Designated a “minimarathon,” the concert is being organized by String Noise, the violin duo of Conrad Harris and Pauline Kim Harris. (They are producing it with Issue Project Room, the Brooklyn experimental-arts venue, in partnership with the Judson Memorial.) The Harrises have assembled a program spanning the composer’s entire repertoire, from the early “Duo for Violins” to the newly composed “What If.” Wolff will improvise with composers David Behrman and John King, colleagues from Merce Cunningham’s company; and with Ikue Mori, a MacArthur grant-winning electronic composer.

His influence, though difficult to define precisely, has continued to grow.

“There’s something in the best way unfinished about Christian’s work,” composer and improviser Michael Pisaro-Liu said in a video interview. Pisaro-Liu, 62, has had a long, close association with Wolff’s music as a member of the Wandelweiser Group, a composers collective profoundly inspired by the New York School, and has played and recorded with Wolff.

“Much as I love Feldman’s music, if you imitate it, it’s always going to be second-rate Feldman, because it’s a highly idiosyncratic and personal language,” Pisaro-Liu said. “Obviously, Cage was immensely influential. But if you’re a composer and you share a lot of Christian’s interests in the agency of the performer, in the social aspect of that, there’s a gold mine of techniques and ideas in the music that you could take up without imitating Christian.”

What makes Wolff’s ingenious achievements even more remarkable is that for most of his life, composition was a sideline to his principal career as a professor, a course he pursued in order to reliably support his growing family. He studied classics and literature at the University of Florence and Harvard University, and then taught classics at Harvard from 1962 to 1970. Arriving at Dartmouth in 1971, he began to teach music for the first time, alongside classics and comparative literature.

A visit to the house in Hanover revealed little to suggest that a composer who works daily at his art is in residence, though Wolff does keep percussion instruments and other assorted noisemakers in the basement. That there is no piano is merely a practical matter: Since Wolff retired from Dartmouth in 1999, he and his wife, Holly, spend most of their time about 40 minutes away, on a farm in Vermont. The piano is there, along with horses, sheep and gardens.

Anyway, he isn’t fussy about working conditions.

“We had four kids,” he said. “I’ve learned to work under almost any conditions whatsoever. My favorite place is just on the kitchen table up at the farm, with people coming in and out.” It’s important to have a piano nearby, he added, but having it in the room where he’s composing is a distraction.

Some argue that, instead of hindering his composing, his divided focus and growing family caused a fundamental evolution in his approach.

“Interruptability,” Michael Hicks and Christian Asplund wrote in a 2012 biography, “had to be taken into account.”

“Collecting ideas and assembling them like a mosaic became habitual,” they write. “And the lessons learned from children (especially rhetorical strategies) insinuated themselves into new works.”

Asked whether his current work constitutes a late style, Wolff chuckles. “It’s late because I’m old, and I’ve been doing this for a ridiculously long time, with lots of interruptions and trying to juggle other stuff.”

He’s obviously aware of the profound, visionary works composers like Ludwig van Beethoven and Giuseppe Verdi wrote in their later years.

“Occasionally I think, am I just repeating myself?” he said. “It seems to me one’s head is just wired in a certain way, and there’s a limit to what you can produce.”

Still, he’s been too busy to worry about it since becoming a full-time musician for the first time in his life, after retiring from teaching. Another new work, “Piece for Seven Percussionists,” will have its premiere in a concert by Talujon at the Roulette performance space in Brooklyn on April 15. Wolff is working on a piano quintet for Ursula Oppens, a longtime friend and champion, and there’s plenty of demand beyond that.

“It’s been 20 years now,” he said, “but I’ve suddenly started really writing a lot of music.”

This article originally appeared in The New York Times.