"You won't find it very often," he admitted in a 1980 Quest magazine interview, "because people are tired and overworked and they just don't have time to think about it. But when they do, the idea of simply living, just making a good living, seems pointless. There is always a question attached to your life, the question of, 'What for?'"

I come from a family that fostered "What for?" questions. This is not to say that we were encouraged to bring home all the derelicts we encountered at the bus station or give state funerals for every dead duck in the park. But it was stressed that everybody is born into the world with an obligation to leave it in better shape than you found it. This seems to me to be a fairly leak-proof aspiration, although my aunt and uncle once had two house guests who stayed up all night cleaning the bathroom tiles to meet their superior standards of cleanliness. Some people don't know when to leave the world alone.

But I have oftentimes wondered whether some people with messiah complexes aren't driven toward saving the world because anything more practical -- like holding down a regular job -- seems too difficult, and whether other people aren't masking an inability to receive anything by constantly being on the give.

I had a neighbor who fits that description. I never baked her a lasagna that she wasn't on the doorstep 30 minutes later with a carrot cake to tilt the record in her favor again. Generosity, when she wasn't on the inside of the chuck wagon, was difficult for her to handle. On the other hand, when two people with messiah complexes live next door to each other it can turn into a pie-throwing contest. Long ago I realized that it was not only better but easier to give.

But even with the purest of motives, the world resists saving. When I was 5 years old, I stayed up all night feeding a litter of baby field mice with milk through an eye-dropper. The next day they were dead. I had mistakenly fed them through the nose.

This is not to say that someone with a messiah complex can simply chuck it when things don't work out. I have a friend who compulsively memorizes license plate numbers and what strangers wear in restaurants on the off chance that he will be called upon as a witness to a bank heist and his photographic memory will save the day. It annoys him that he can't stop doing this. But it is a habit he cannot resist. I always wish I carried blankets, pillows and a rope in my car trunk, in case I am the only person on the scene when an airplane dives into the Potomac. Actually, my trunk carries only one flat tire that is minus a wheel because I keep forgetting to reclaim it from the gas station. But mentally I am a Red Cross wagon, cruising for a crash. There are, however, genuine "messiahs'" in any community. They do not perceive of themselves as exceptional. And they are often quite wry about themselves, like Father George, a Jesuit priest who bicycles between local playgrounds in Northwest Washington after he finishes teaching Byzantine history at Catholic University. It is an unsalaried, volunteer assignment he gave himself a long time ago. He simply "hangs around," like a nonjudgmental uncle, talking to the teenage boys at the parks.

"I like the kids -- probably because I don't have to live with the little buggers," said Father George, who has known most of the boys since they were in grade school. And knowing who they really are, beneath the long hair, bandannas and scowling expressions, is probably why Father George is accepted without question.

"I try to hit all of the parks in the afternoon, just to keep up on things. But I don't always hit the parks where I have to do a lot of pedaling uphill." Real do-gooders give the impression that saving the world is done by pedalling down the path of least resistance, which makes them irresistible -- and irreplaceable when they are gone.

Joan Doniger, a long-time Washington resident, died 10 years ago. An angular, dark-eyed woman who had a penchant for wearing shapeless Mary Jane-style flats and cardigan sweaters, Doniger was beautiful and gawky in combination. But there was nothing gawky about her mind.

She once remarked that she had never held a job that trained her for what she wound up doing -- founding Woodley House, a halfway residence for the formerly mentally ill before they re-entered the world. People who did not fit into Sears, Roebuck sizes didn't fluster her. The one-armed paper-hanger she employed at Woodley House wound up becoming my one-armed paper hanger. Her judgments about people were rarely wrong.

When her ailing father needed nursing treatment, Doniger decided that she wouldn't commit him to the indignities that she envisioned were part of institutional housing. Instead, she scraped up the money to rent another house in her neighborhood, found two other elderly men who needed constant attention, combined their finances and hired nurses. "I only need two nurses, but I hired a spare, just to keep the other two on their toes."

She never married. But it suddenly occurred to her that a lack of a husband should not get in her way of something she wanted to do: have children. She was one of the first single women to adopt children in the city, and when Kiyo and Teresa were adopted, the keyboard of her life expanded. Not a day went by that she did not exult over her good fortune. She was a natural mother, quite literally, until the last second of her life.

I, too, was an adoptive parent. We once discussed what we would say when our children asked why their first mothers had given them away. "I will probably say," I rehearsed, "that it was an act of love, that your mother cared enough about you to make sure that you had a good home." Joan nodded. "I'm going to tell Kiyo that her mother was stupid. She didn't know who she was giving up."

On the morning that Joan Doniger died, she telephoned me. It was a hasty conversation. I promised I would call her back when I had time to talk. The next telephone call, late that afternoon, came from a friend of Joan's, reporting that she had been killed by a taxicab whose drunken driver had run her down on a New York sidewalk.

"No," I protested. "You're mistaken. I just talked to her in Washington today." But it was as true as her final gesture before the cab hit her.

Joan was standing on the sidewalk holding 4-year-old Kiyo in her arms when she saw the taxi bearing down. In the split second that remained, she hurled Kiyo -- with a mightly thrust -- away from her.Then her time ran out, but not before she had saved the part of the world she loved most.