TV writer/producer Norman Lear, who died Tuesday at his home in Los Angeles at the healthy age of 101, enjoyed a career that stretched more than half a century, from the dawn of the medium to South Park. But he’s best remembered for the half-decade in the early 70s when he had as many as five hit comedies in primetime. During that brief period, he completely rewrote the rules of television, demonstrating that the situation comedy could address topical and controversial issues without sacrificing laughs or heart—or ratings.

Born in New Haven, Connecticut, Lear became a pilot in World War II and flew 52 combat missions. Moving to Hollywood to be a comedy writer, he got his first big break when he tricked a receptionist into giving him Danny Thomas’s phone number, then rang up the comic and sold him a routine over the phone.

Soon Lear was working as a writer and director on TV variety shows. In 1958, he and Bud Yorkin founded Tandem Productions, the shingle under which they’d produce their legendary 70s sitcoms. Meanwhile, Lear continued to hone his craft and even broke into movies, earning an Oscar nomination for his 1967 screenplay, Divorce, American Style and writing and directing the anti-smoking satire Cold Turkey in 1971. But what altered his career forever were two British shows: Til Death Do Us Part and Steptoe and Son, that he would transform into his first American sitcom hits, All in the Family and Sanford and Son.

Lear made over TV in his own image. What appealed to him about Til Death, and what he replicated in All in the Family’s battles between Archie and Meathead, was the similarity to Lear’s arguments with his own father. Sanford and Son had a similar father-son dynamic. In Maude, the main character embodies both the blowhard parent and the liberal child. In The Jeffersons and Good Times, the families happen to be black, but the angry father is still there.

Lear had the good fortune to come along at a time when network TV—and CBS in particular—wanted to change its image. Television comedy had spent most of the 60s conspicuously avoiding the decade’s real-life controversies and schisms. CBS had a number of homespun hit shows like The Beverly Hillbillies and Green Acres, but the network accountants had discovered that, rather than broadcast shows the whole nation might enjoy, it could make more money narrowcasting, catering to the affluent, younger, metropolitan audiences. Despite their high ratings, the networks tossed those programs in favor of shows like Lear’s, as well as The Mary Tyler Moore Show, M*A*S*H, and The Bob Newhart Show. These shows, too, made topical references and assumed a progressive audience, but not to the extent that All in the Family did.

Lear deliberately courted controversy with his shows (a famous early episode of Maude addressed abortion with a pro-choice fervor that no TV comedy or drama has displayed in the more than four decades since), but Archie Bunker became much more than the bigot you were supposed to love to hate. Brought to uncompromising but sympathetic life by star Carroll O’Connor, Archie became a hero to some (the loudmouth voice of Nixon’s “silent majority”) and was regarded as a lovable, hard-working dad, even if you found his opinions appalling.

Yet all those cathartic arguments made for great ratings and great television. Lear and his shows won a slew of Emmys throughout the early 70s, at a time when he had five of the biggest hits on TV (All in the Family, Sanford, Family spinoffs Maude and The Jeffersons, and Maude spinoff Good Times.)

Lear continued to produce hit comedies throughout the 70s and 80s (his company’s hits would include Diff'rent Strokes, The Facts of Life, and 227), but he was less hands-on with the writing, and the shows became less controversial and more conventional. In fact, TV as a whole seemed to undergo the same shift. Garry Marshall and Aaron Spelling became TV’s top producers, with shows that were, once again, frivolous , frothy, and insulated from current events. Lear turned his attention largely to movies, helping make Rob “Meathead” Reiner into an A-list director by financing his first four films.

Still, the precedents Lear set remained for others to emulate, particularly primetime’s animators. Archie Bunker lives on in Homer Simpson, Peter Griffin, and Eric Cartman. In fact, South Park creators Trey Parker and Matt Stone so admired Lear as a provocateur that they had him co-write a 2003 episode and voice a role as Benjamin Franklin, and Lear even officiated at Parker’s 2006 wedding.

The Franklin role was fitting, since Lear had also earned fame as an activist for constitutional civil liberties. In 1981, he founded People for the American Way, dedicated to preserving First Amendment rights. In 2001, he sent his own copy of the Declaration of Independence (from the original 1776 print run) on tour across America as a gesture of inspiration and education. (Maybe that explains why *All in the Family* and other Lear shows have been such enduring hits; after all, that argument between the liberal child and the conservative parent is right there in America’s founding document.)

And in 2017, he made headlines at the age of 95 when he was awarded a Kennedy Center Honor—but refused to attend a White House reception hosted by President Donald Trump. He also imbued his liberal views into One Day at a Time, the 2016 Netflix remake of Lear’s sitcom about a single mother and her family, which originally ran from 1975 to 1984.

The success of that reboot spurred Lear into a new creative period, despite his age; in 2018, he developed an NBC pilot about a community of senior citizens called Guess Who Died. Perhaps he would have considered bringing a new-fangled version of Archie Bunker back onto the small screen as well: “I think it would work because I don’t think people have changed,” he told Vanity Fair in 2018. “The audience is the same audience it was in the 70s—same human beings with the same frailties, same problems, same needs.”