One memorable winter evening a few weeks after he received the Nobel Peace Prize in 1976, Andrei Sakharov and his wife, Elena Bonner, came to our apartment in Moscow for supper. It was clearly an occasion. Sakharov had never been in an American's home before, and he was as curious as we were delighted to have him. Bonner wore the same dress in which she had accepted the Nobel for him (Sakharov was not allowed to leave the country himself), and the laureate was spiffier than I had ever seen him in a three-piece suit and new Italian tie.

Sakharov surveyed the apartment with fascination. He wondered whether the imported pretzels had been made by machine and marveled at a walk-in storage closet (ordinary Soviet apartments don't have closets). But most of all he was taken by the washer/dryer crammed into our bathroom. At one point, he stuck his whole head inside it to see how it worked. You see, this great Soviet physicist had never been abroad, and a contraption like ours, compared with the primitive home-grown variety, left him shaking his head in wonder.

That evening was one of the few times that I saw Andrei Sakharov relaxed -- as happy, it seemed, as a life of his enormous burdens would permit. After all, being a symbol of human rights and freedom in the Soviet Union, challenging the Kremlin for a decade, is, aside from everything else, exhausting.

It is worth remembering that the pressure on Sakharov has been excruciating. In a quiet aside at dinner that night, I asked Elena Bonner how long Sakharov could go on. He was nearing 60 and his health had suffered. It's hard, she confided, because being a symbol is not something you can announce you're retiring from and go off to the seashore on a pension. The Soviets won't exile Sakharov in the West, she said, because of the nuclear secrets in his head. They could throw him in jail or, she added softly, someday they might just run them both over with a car and say it was an accident.

The fear was well founded. About the time, the Sakharovs began receiving in the mail photographs of horrible automobile collisions, plainly meant to be a perverse warning from the KGB.

Over the past eight years, the Sakharovs have been threatened more times than they could possibly count. In 1973 two men who claimed they were Arabs came to Sakharov's home and said they would kill him if he issued another statement in support of Israel. In 1978 he received a series of telephone warnings from a self-described Russian terrorist organization. Hardly a week went by without some menacing move by the authorities against them, their close friends or relatives.

No wonder there were times when Sakharov visibly flagged. He would sit at dissident press conferences in his own apartment or others, his head bowed, his eyes half-closed, listening to reports of continuing, relentless repression that increasingly he understood he could not stop and would eventually lead to him.

Yet with Elena Bonner's help he always managed to revive. Almost every day a stream of visitors came to see him. Some were local -- like a veteran who badly needed a prosthetic advice obtainable only in West Germany and thought Sakharov could help, or a Pentecostalist desperate to emigrate. Some were foreign -- U.S. senators, traveling journalists, luminaries of various kinds. He listened patiently to them all, responding to entreaties as best he could, answering their repetitive questions and issueing appeals that tended -- lately at least -- to get lost in the rush of dramatic events elsewhere.

So now, in the aftermath of international furor over the invasion of Afghanistan, the Soviets have moved to silence Andrei Sakharov. The allegations of treason against him in the official press are chilling. At the very least he apparently faces internal exile in the closed city of Gorky, where his access to the world will obviously be sharply reduced.

But while the words may be muffled and the weary physical presence removed, the image of eloquent defiance that Sakharov represents will not be erased. He survives. As Elena Bonner observed, it's not that easy to remove a symbol.