As benefits go, it was one of your more serious events. This is not to say that it was lacking in chic.

Paul Simon sang songs from a Russian work camp, Arlo Guthrie, in a cowboy shirt, sang of an executed Chilean musician. Leonard Bernstein played a Greek freedom song. Novelist William Styron, in one of the most moving scenes of the night, made many of the elegant crowd of 800 weep when he read "Lonely Paradise" by Prambed ya Ananta Toee, a story of a man murdered for his political beliefs.

Titled "The Night of the Empty Chair" and performed at the Manhattan Ethical Culture Society, the two-hour benefit was dedicated to artists and writers who have been imprisoned, tortured or killed for their beliefs. To this end, two dozen American writers and actors, including Richard Widmark, Studs Terkel, Muriel Rukeyser, Arthur Miller and Robert Penn Warren read and performed from the works of their persecuted peers.

One of the few light moments of the show, which will be televised in January on public television, came when narrator Art Buchwald teased the audience (some of whom had paid $100 a ticket and comprised New York's most visible party people;) about the new found respectability of Amnesty International. Last month, that 16 year-old human-rights organization, dedicated to freedom for political prisoners, was awarded its second Nobel Peace Prize.

"Suddenly, Amnesty International is a very 'in' organization," Buchwald pretended to complain. "President Carter has co-opted us; and to make matters worse, we've received the Nobel Prize - and all the fun is gone out of it.

"We live in a country where we can attack the system without fear of meeting the fate of the people we remember tonight," Buchwald continued. "When we attack the government here, they do something far worse than throw you in prison. They make you a member of the establishment . . . any radical can now earn a fortune trying to convert executives of IBM."

Arlo Guthrie, a benefit old-timee (he did one just last week for Oxford Students Against Famine; but since it was held the same day as No Smoking Day, no one paid much attention), refused to judge the show as entertainment. "That's not the point" He also said that he recognized a lot of the people in the audience from the last benefit he did in New York, for American Indians.

Following the performance, the 200 persons who had paid $100 a ticket (as opposed to the 600 who had paid $20) repaired to the Tavern-on-the-Green to supper, to endure the Paparazzi (Lauren Btcall was their favorite) and to review the performance. Everyone agreed that, though awfully touching, the show had been too long, accoustically awful and otherwise flawed.

Paul Simon, in blue jeans and pull over sweater, fretted about having forgotten the chords to his song on stage, wondered if he should re-do it for TV and confided to Leonard Bernstein that he had been afraid that his Russian work-camp song "sounded like a parody of an old Theo Bikel." Bernstein, in turn, moaned about his own disastrous duet, the show's grand finale. "I was supposed to be accompanying this kid with the bouzouki when his mike went dead, and this poor kid frozq; and instead of this big sound, he's got this little tinky-tinky-tinky and I'm accompanying nothing; I'm sitting there with my fly open."

How seriously did this group, which listed among its sponsors New York party regulars like Phyllis Cerf Wagner, Mr. and Mrs. Stephen Smith, publisher Thomas H. Guinzberg and Peter Duchin, take the concerns of political prisoner?

Hard to say. But leaping to their defence was Berntein, after whom the phrase "radical chic" was coined by Tom Wolfe back in the '60s when Berstein threw a Black Panther fund-raiser.

"How many here care? A great many,"said Berntein, who raised fund for Amnesty International last year when bankrupt."Oh, I know it's easy to be cynical about people coming together for human rights-that whole horrid Panther story-it was all made up; there was only one Panther even at that party, but it will haunt me to my grave. Tom Wolfe is horrid and a faker; talented, but a fake.

"And I know the names people call us:'bleeding hearts;'liberals','do-gooders'-and our hearts do bleed, and we do do good, and we are liberals and we do cry. I saw Sadat and Begin sitting on a couch talking about their grandchildren, these two world leaders talking about their grandchildren because Sadat had just had a grandchild, and the tears came out of my eyes. But don't be cynical about us, just to sell more papers. We're for real, this is for real."