NEW YORK, NY.- Elinor Fuchs, whose impassioned insights into contemporary theater — first as a critic prowling the avant-garde scene in New York, and later as a professor at Yale — made her one of the leading scholars of the modern American stage, died May 28 at her home in the West Village of Manhattan. She was 91.

Her daughter Katherine Eban said the cause was complications of Lewy body dementia.

Fuchs specialized in dramaturgy, or the construction of a play, including its dramatic structure, its characters’ motivations and technical issues about set design and lighting.

In conventional times, dramaturgy can seem to be an arcane, even slightly stuffy field. But in Fuchs’ hands, it became a vital tool for examining the revolutionary new forms of theater emerging in the 1960s and ’70s, forms that complicated — or dismissed entirely — conventional notions about character, dramatic arc and authorial intention.

Unlike many other theater scholars, Fuchs first came at these questions from a journalistic point of view. After attempting a career as an actor and writing a play, she turned to freelance theater criticism for what was then a bountiful crop of alternative weeklies around Manhattan, including The Village Voice and The SoHo Weekly News.

She found herself drawn to challenging works like “Leave It to Beaver Is Dead,” a 1979 play at the Public Theater that included a full-length rock concert as a third act. The New York Times panned it, and it soon closed.

But Fuchs loved it, recognizing the play and other experimental fare as not just a new take on theater but also a whole new, postmodern cultural sensibility — even though at first she struggled to explain it.

“For this vertiginous new perspective, at once artistic and broadly cultural, I lacked at the time a name, much less an adequate vocabulary and grammar,” she wrote in her 1996 book, “The Death of Character: Perspectives on Theater After Modernism.”

She found herself turning to Europe, where thinkers like Roland Barthes, Jean Baudrillard and Jacques Derrida were asking radical questions about art, literature and culture, offering insights that enabled Fuchs to explain what she was seeing in the cramped theaters of lower Manhattan.

She wrote extensively about pioneering playwrights and troupes like Robert Wilson, Mabou Mines and the Wooster Group, translating her knowledge of French literary theory into terms that general readers could grasp, a form of code-switching that made her one of the most important interpreters of experimental theater of the late 20th century.

“There’s just a kind of hard-won, boots-on-the-ground knowledge that comes from seeing theater night after night and having to write about it,” David Bruin, a drama instructor at New York University who studied with Fuchs at Yale, said in a phone interview. “It just brought her whole body of work into focus.”

Among theater students and professors, Fuchs is perhaps best known for “EF’s Visit to a Small Planet,” a short essay she wrote soon after arriving at Yale in 1987 that soon became required reading in theater programs nationwide.

The article offers guidance on how to approach a play, in the process unpacking the core of Fuchs’ entire critical philosophy. Unlike reality, she wrote, everything in a play is intentional; whether realist or abstract in its presentation, it is its own world, and has to be approached that way.

“To see this entire world, do this literally: Mold the play into a medium-sized ball, set it before you in the middle distance, and squint your eyes,” she wrote. “Before you is the ‘world of the play.’”

Elinor Clare Fuchs was born Jan. 23, 1933, in Cleveland. Her father, Joseph Fuchs, was a violinist and concertmaster with the city’s orchestra and later a longtime teacher at Juilliard. Her parents divorced when Fuchs was 4 years old. Leaving Fuchs in the care of her grandparents, her mother, Lillian Kessler, moved to Washington, D.C., where she founded Kessler International, an export company specializing in machine tools. Fuchs joined her when she was about 9.

Like her mother, Fuchs attended Radcliffe College, graduating in 1955. That same year she married Stanley Palombo, though they divorced about a year later.

She married Michael Finkelstein in 1962. They divorced in 1977. In addition to Eban, she is survived by another daughter, Claire Finkelstein, and four granddaughters.

Fuchs moved to New York to pursue an acting career and earned enough credits to get her Screen Actors Guild card; she also modeled for the covers of paperback romances and thrillers.

In 1973, she and Joyce Antler published “Year One of the Empire,” a play, written in the form of a staged documentary, about the expansion of American power. It was first staged in 2008 by Metropolitan Playhouse, to rave reviews.

The Times called it “an enlightening, entertaining and at times engrossing dramatized survey of America’s coming of imperialistic age at the turn of the 20th century.” It won an award for best play from Drama-Logue magazine (now part of Backstage).

Fuchs received her master’s degree in theater studies from Hunter College in 1975, and she received her doctorate in the same subject from the City University of New York in 1995.

In the late 1980s, Kessler developed Alzheimer’s disease, and Fuchs spent several years caring for her. After her mother died, Fuchs wrote a memoir about the experience, “Making an Exit” (2005), in which she reflected on how her training in theater helped her cope with her mother’s condition.

“Mother exclaimed, ‘We can do it!’ 30 times in 10 minutes on her 84th birthday, radiating a zany good cheer,” she wrote in the Times in 2005. “By this time I was assigning the plays of Gertrude Stein to my students. If Stein could raise repetition to an art form, if Beckett and Philip Glass could do it, why not relax and enjoy it when it came from Mother?”

This article originally appeared in The New York Times.