TOM CAME BACK the other day. It has been four years. He came back to the newsroom where once he had worked as an editor and later as a writer and everyone came out to greet him. He stood in the middle of small groups. A smiling, high-cheeked, bearded man of 35, tanned by the sun of the Colorado mountains and dressed for the woods - plaid shirt, work pants and climbing boots. Everyone asked him how he was and everyone said they were happy to see him but no one said anything about what is called "dropping out" and no one, of course, asked him if it works. It does, he would say. That is what he says.

It was four years ago exactly when he left.He left his career and his wife and his children and his house in the suburbs. He did not do that all at once. He changed mentally, physically and spiritually, but once he was a crew-cutted man with a family in the suburbs and a life membership in some car pool. Now he lives in the mountains of Colorado, a place called Gold Hill. He writes a bit and works a bit, getting by selling articles and painting houses and delivering phone books and counting traffic in the city of Boulder. A lot of the time, though, he walks into the woods and sits by a stream and listens to the silence of the mountains.

He was not the first to go, of course. There have been others. They make their declarations and they say they've had it and they say they are going back to a simpler life, to better values, to a slower pace and more genuine people and . . . and then a year or two later they call. They ask for their old job back. They are contrite. They are humble. They justify your life.

Not Tom. He is different, He had problems, but he was a sweet talent. Sometimes when he wrote he made you read once for what he said and once more for the way he said it. He was that good and he sat next to me and then he went away. When he came back I wanted to know if he had managed to make it work and I wondered if the others had wondered, too.

"Nobody voices anything," he said, "Nobody says anything. It was just that look in their eyes. There really was a look in most people's eyes. It let me know that they wanted to do what I did. It also let me know that they wished they were the kind of people who could do it. I guess not too many people act out their fantasies."

He was sitting at an open window when he said that, with the sun behind him, and I thought about a couple I had met at the beach some years ago. They were dropouts of sorts and their story, told to us by the woman, is lost to me now. But they were college people, you could tell that, and they had decided to chuck it all. They took a house on the road leading out to the dunes and he became a fisherman and she went to work in a store that sold wine and cheese to the summer people. Every summer we would see her and every summer I would want to ask how it was going. Was there enough money and did they miss the city? Didn't he want deep down to be a smashing success, someone his mother could talk about by the pool (My son the fisherman?) and were they really going to do this forever? I mean, who was going to pay for the kid's education? This summer, she was gone and I never got to ask the questions. I was relieved.

Now Tom and I are talking. He is living and working at the office of the National Organization for the Reform of Marijuana Laws, writing a book for that organization. He tells me how he changed and how it was nothing sudden, not like the New York bus driver, for instance, who once day simply drove his bus to Florida. Nothing like that. But the time did come when he was in Colorado with his two children and he simply looked around and it occurred to him that he could live there.

"One afternoon, I just said, 'I could live here." It just dawned on me. It just struck me. I could do that." So he did. He waited for his tax refund and he left that was four years ago. He lives in a cabin of some sort with a woman and her two children and he laughs that now he is a good father but not to his own kids. He works around and he has lived on unemployment and he has no shame about that. The system, he says, is fat and he helped make it fat and now he is taking some.

I ask the questions, he answers them. We go down the list. What do you miss? Do you miss this or that? Finally I ask about old age? All this and your mind begins to sputter and you have no pension and no insurance and not even a gold watch for meritorious service that you can hock. Yes, he has thought about that. Yes. I'm cheered. I got him.

"My parents and everybody in my family prepared for getting old by saving their money. And then the month after he turned 50, my father dropped dead of a heart attack. I just don't want to do that. The best way to prepare for old age is to live high and live well. Sometimes I get flashes - what am I doing way out a limb. Sometimes when my kids are about to go hom I get a flash about how much I left behind."

In two weeks, he will finish his work here and go back to the mountains. He makes no vows. Maybe he'll come back, put on a tie, go for the brass ring - buy something on time.

We'd all feel better.