Although he was popular long before and after it, comedian George Carlin was famous for one routine.

"Seven Words You Can Never Use on Television" shot Carlin to national stardom. In it, the comedian, who died of heart failure Sunday at 71, specified seven words that never could be said on television -- or on the radio or in newspapers.

In 1972, when he performed the routine on stage in Milwaukee, he was arrested and charged with disturbing the peace.

A judge dismissed the charges on the grounds of freedom of speech, but in 1975 a New York City radio station's broadcast of his "Filthy Words" routine led to a Federal Communications Commission complaint against the foundation that owned the station.

The case went to the U.S. Supreme Court, which held in 1978 that the FCC does have the right to regulate what kind of words are used over the public airwaves.

"He won, even though he lost," said Joan Bertin of the National Coalition Against Censorship in New York City.

"In his comic way, he raised some very serious questions about how far the federal government can go in regulating what is broadcast. While his case didn't prevail, he has made the issue immortal through his comic routines."

Carlin's seven words remain taboo today.

Ronald K.L. Collins, a Washington-based scholar with the First Amendment Center, pointed out that Carlin's death comes at a time when the Supreme Court is considering a case in which the FCC is attempting to fine the Fox television network for two instances of "fleeting expletives" spoken over the air.

"Just about the time that the U.S. Supreme Court is considering the Fox case, the nation will be honoring George Carlin," Collins said. "The irony is just breathtaking."

Collins said Carlin had an all-American independent streak -- an untamed side that resonated with liberals and conservatives alike.

"George Carlin was in many ways the living embodiment of the First Amendment, of the idea that an American can speak his mind as he thinks it, as he feels it, and can speak it openly," Collins said.

"He didn't like euphemisms; he liked the naked truth in all its splendor and all its vulgarity."

Carlin and others have helped to move the culture toward an acceptance of words that once were considered offensive, Collins said. As the culture moves toward this openness, he predicted that laws against obscenity will follow suit.

Bertin, of the National Coalition Against Censorship, said, "For many people, what he did was he demystified the words. By making fun of them and saying them over and over and over again, he showed how you could take some of the power away."

Catherine Ingrassia, a professor of English at Virginia Commonwealth University, agrees. Unlike some comedians who make gratuitous use of profanity -- she cited Andrew Dice Clay as one example -- Carlin used the words to effect social change.

"Carlin uses it as a vehicle for political commentary and makes us aware of the arbitrary boundaries we put on ourselves," she said.

Kent Willis of the American Civil Liberties Union of Virginia said Carlin spoke from the fringes of society and that the fights to protect his speech also wound up helping to protect the speech of those in the mainstream.

"There was a renaissance of free speech that came out of the courts in the'60s and'70s," he said. "Carlin rode that wave."

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