Caroll Spinney, the puppeteer who played Big Bird and Oscar the Grouch on Sesame Street from the show’s 1969 debut until his retirement in 2018, died Saturday at his home in Connecticut at the age of 85, the New York Times reports. Sesame Workshop, the non-profit that produces Sesame Street, summed up Spinney’s contributions to American culture in a statement:

His enormous talent and outsized heart were perfectly suited to playing the larger-than-life yellow bird who brought joy to generations of children and countless fans of all ages around the world, and his lovably cantankerous grouch gave us all permission to be cranky once in a while.

That’s a pretty good description of Spinney’s work and its impact, if you have to do it using words. You could tell the same story through the various honors Spinney received for his life’s work: four Daytime Emmys and a lifetime achievement award from the National Academy of Television Arts and Sciences, two Grammys from the Recording Academy and a Living Legend award from the Library of Congress. The easiest way to understand what a treasure Spinney was, however, is probably by watching him perform Oscar the Grouch’s signature song, “I Love Trash.” It’s an absolute masterpiece, from Spinney’s voice—based on a cabbie who treated him to an unsolicited lecture about John Lindsay on the way to the show on his first day—to his extraordinary skill at making a hunk of fabric and plastic come to life. His delivery of “Love … yuck!” easily stands alongside the best work of human actors, who have the distinct advantage of using their own personal eyebrows to convey emotion, instead of pulling on an eyebrow lever like Spinney.

Spinney also played Big Bird, a full-body puppet who eventually evolved into a surrogate for the show’s young audience. Here’s the 1985 scene in which Big Bird finally introduces the adult cast to his best friend, Mr. Snuffleupagus. Snuffleupagus had been a running joke since his introduction in 1971—the adults on the show believed him to be Big Bird’s imaginary friend, when in fact he was just shy and reclusive—but rising awareness of child abuse in the 1980s made the staff less comfortable with a recurring plotline in which adults refuse to believe that a child (or an enormous bird) is telling the truth about their experiences. Snuffy’s introduction to the adults became a television event, but Spinney’s performance, carefully helping children navigate their own emotions, was not out of the ordinary—he was always this good.

As for Spinney, the man who quietly played such an outsized role in so many childhoods, he remained relatively anonymous, even as his puppets became icons. Spinney was profiled in directors Dave LaMattina and Chad N. Walker’s 2014 documentary I Am Big Bird: The Caroll Spinney Story, and by all accounts seems to have been as kind and loving as his feathered alter-ego. Here’s a brief tribute Sesame Workshop put together when Spinney retired in which he reflects on his life and work There’s also footage of the original versions of Big Bird and Oscar from Sesame Street’s pilot—Big Bird was much sillier-looking and Oscar was orange—but the highlight here comes from the landmark 1983 episode that dealt with the death of Sesame Street character Mr. Hooper, which the show decided to address head-on after actor Will Lee died of a heart attack. Because Spinney’s performance is pitched toward young children, it’s easy to miss how carefully he honors the full range of children’s emotions about death—showing not just sadness, but bewilderment and anger—while keeping Big Bird’s essential curious, friendly nature intact.

But the single best showcase for Spinney’s talents may be a short scene he shared with Danny DeVito in 1988, when DeVito appeared on Sesame Street as “Vincent Von Grouch,” the curator of the Museum of Trash. Because the scene’s content is straight-up nonsense, the genius of Spinney’s puppeteering stands out, especially while DeVito is talking: Oscar’s double-takes, sighs, and frenetic head shaking are absolute virtuoso work.

Since it’s the holiday season, it seems appropriate to say goodbye by revisiting “I Hate Christmas,” a bracing blast of humbug Spinney performed in the 1978 special Christmas Eve on Sesame Street.

Thanks for everything, you old grouch.