''I don't regret setting bombs,'' Bill Ayers said. ''I feel we didn't do enough.'' Mr. Ayers, who spent the 1970's as a fugitive in the Weather Underground, was sitting in the kitchen of his big turn-of-the-19th-century stone house in the Hyde Park district of Chicago. The long curly locks in his Wanted poster are shorn, though he wears earrings. He still has tattooed on his neck the rainbow-and-lightning Weathermen logo that appeared on letters taking responsibility for bombings. And he still has the ebullient, ingratiating manner, the apparently intense interest in other people, that made him a charismatic figure in the radical student movement.

Now he has written a book, ''Fugitive Days'' (Beacon Press, September). Mr. Ayers, who is 56, calls it a memoir, somewhat coyly perhaps, since he also says some of it is fiction. He writes that he participated in the bombings of New York City Police Headquarters in 1970, of the Capitol building in 1971, the Pentagon in 1972. But Mr. Ayers also seems to want to have it both ways, taking responsibility for daring acts in his youth, then deflecting it.

''Is this, then, the truth?,'' he writes. ''Not exactly. Although it feels entirely honest to me.''

But why would someone want to read a memoir parts of which are admittedly not true? Mr. Ayers was asked.

''Obviously, the point is it's a reflection on memory,'' he answered. ''It's true as I remember it.''

Mr. Ayers is probably safe from prosecution anyway. A spokeswoman for the Justice Department said there was a five-year statute of limitations on Federal crimes except in cases of murder or when a person has been indicted.

Mr. Ayers, who in 1970 was said to have summed up the Weatherman philosophy as: ''Kill all the rich people. Break up their cars and apartments. Bring the revolution home, kill your parents, that's where it's really at,'' is today distinguished professor of education at the University of Illinois at Chicago. And he says he doesn't actually remember suggesting that rich people be killed or that people kill their parents, but ''it's been quoted so many times I'm beginning to think I did,'' he said. ''It was a joke about the distribution of wealth.''

He went underground in 1970, after his girlfriend, Diana Oughton, and two other people were killed when bombs they were making exploded in a Greenwich Village town house. With him in the Weather Underground was Bernardine Dohrn, who was put on the F.B.I.'s 10 Most Wanted List. J. Edgar Hoover called her ''the most dangerous woman in America'' and ''la Pasionara of the Lunatic Left.'' Mr. Ayers and Ms. Dohrn later married.

In his book Mr. Ayers describes the Weathermen descending into a ''whirlpool of violence.''

''Everything was absolutely ideal on the day I bombed the Pentagon,'' he writes. But then comes a disclaimer: ''Even though I didn't actually bomb the Pentagon -- we bombed it, in the sense that Weathermen organized it and claimed it.'' He goes on to provide details about the manufacture of the bomb and how a woman he calls Anna placed the bomb in a restroom. No one was killed or injured, though damage was extensive.

Between 1970 and 1974 the Weathermen took responsibility for 12 bombings, Mr. Ayers writes, and also helped spring Timothy Leary (sentenced on marijuana charges) from jail.

Today, Mr. Ayers and Ms. Dohrn, 59, who is director of the Legal Clinic's Children and Family Justice Center of Northwestern University, seem like typical baby boomers, caring for aging parents, suffering the empty-nest syndrome. Their son, Malik, 21, is at the University of California, San Diego; Zayd, 24, teaches at Boston University. They have also brought up Chesa Boudin, 21, the son of David Gilbert and Kathy Boudin, who are serving prison terms for a 1981 robbery of a Brinks truck in Rockland County, N.Y., that left four people dead. Last month, Ms. Boudin's application for parole was rejected.

So, would Mr. Ayers do it all again, he is asked? ''I don't want to discount the possibility,'' he said.

''I don't think you can understand a single thing we did without understanding the violence of the Vietnam War,'' he said, and the fact that ''the enduring scar of racism was fully in flower.'' Mr. Ayers pointed to Bob Kerrey, former Democratic Senator from Nebraska, who has admitted leading a raid in 1969 in which Vietnamese women and children were killed. ''He committed an act of terrorism,'' Mr. Ayers said. ''I didn't kill innocent people.''

Mr. Ayers has always been known as a ''rich kid radical.'' His father, Thomas, now 86, was chairman and chief executive officer of Commonwealth Edison of Chicago, chairman of Northwestern University and of the Chicago Symphony. When someone mentions his father's prominence, Mr. Ayers is quick to say that his father did not become wealthy until the son was a teenager. He says that he got some of his interest in social activism from his father. He notes that his father promoted racial equality in Chicago and was acceptable as a mediator to Mayor Richard Daley and the Rev. Dr. Martin Luther King Jr. in 1966 when King marched in Cicero, Ill., to protest housing segregation.

All in all, Mr. Ayers had ''a golden childhood,'' he said, though he did have a love affair with explosives. On July 4, he writes, ''my brothers and I loved everything about the wild displays of noise and color, the flares, the surprising candle bombs, but we trembled mostly for the Big Ones, the loud concussions.''

The love affair seems to have continued into adulthood. Even today, he finds ''a certain eloquence to bombs, a poetry and a pattern from a safe distance,'' he writes.

He attended Lake Forest Academy in Lake Forest, Ill., then the University of Michigan but dropped out to join Students for a Democratic Society.

In 1967 he met Ms. Dohrn in Ann Arbor, Mich. She had a law degree from the University of Chicago and was a magnetic speaker who often wore thigh-high boots and miniskirts. In 1969, after the Manson family murders in Beverly Hills, Ms. Dohrn told an S.D.S. audience: ''Dig it! Manson killed those pigs, then they ate dinner in the same room with them, then they shoved a fork into a victim's stomach.''

In Chicago recently, Ms. Dohrn said of her remarks: ''It was a joke. We were mocking violence in America. Even in my most inflamed moment I never supported a racist mass murderer.''

Ms. Dohrn, Mr. Ayers and others eventually broke with S.D.S. to form the more radical Weathermen, and in 1969 Ms. Dohrn was arrested and charged with resisting arrest and assaulting a police officer during the Days of Rage protests against the trial of the Chicago Eight -- antiwar militants accused of conspiracy to incite riots at the 1968 Democratic National Convention.

In 1970 came the town house explosion in Greenwich Village. Ms. Dohrn failed to appear in court in the Days of Rage case, and she and Mr. Ayers went underground, though there were no charges against Mr. Ayers. Later that spring the couple were indicted along with others in Federal Court for crossing state lines to incite a riot during the Days of Rage, and following that for ''conspiracy to bomb police stations and government buildings.'' Those charges were dropped in 1974 because of prosecutorial misconduct, including illegal surveillance.

During his fugitive years, Mr. Ayers said, he lived in 15 states, taking names of dead babies in cemeteries who were born in the same year as he. He describes the typical safe house: there were usually books by Malcolm X and Ho Chi Minh, and Che Guevara's picture in the bedroom; fermented Vietnamese fish sauce in the refrigerator, and live sourdough starter donated by a Native American that was reputed to have passed from hand to hand over a century.

He also writes about the Weathermen's sexual experimentation as they tried to ''smash monogamy.'' The Weathermen were ''an army of lovers,'' he says, and describes having had different sexual partners, including his best male friend.

''Fugitive Days'' does have moments of self-mockery, for instance when Mr. Ayers describes watching ''Underground,'' Emile De Antonio's 1976 documentary about the Weathermen. He was ''embarrassed by the arrogance, the solipsism, the absolute certainty that we and we alone knew the way,'' he writes. ''The rigidity and the narcissism.''

In the mid-1970's the Weathermen began quarreling. One faction, including Ms. Boudin, wanted to join the Black Liberation Army. Others, including Ms. Dohrn and Mr. Ayers, favored surrendering. Ms. Boudin and Ms. Dohrn had had an intense friendship but broke apart. Mr. Ayers and Ms. Dohrn were purged from the group.

Ms. Dohrn and Mr. Ayers had a son, Zayd, in 1977. After the birth of Malik, in 1980, they decided to surface. Ms. Dohrn pleaded guilty to the original Days of Rage charge, received three years probation and was fined $1,500. The Federal charges against Mr. Ayers and Ms. Dohrn had already been dropped.

Mr. Ayers and Ms. Dohrn tried to persuade Ms. Boudin to surrender because she was pregnant. But she refused, and went on to participate in the Brink's robbery. When she was arrested, Ms. Dohrn and Mr. Ayers volunteered to care for Chesa, then 14 months old, and became his legal guardians.

A few months later Ms. Dohrn was called to testify about the robbery. Ms. Dohrn had not seen Ms. Boudin for a year, she said, and knew nothing of it. Ms. Dohrn was asked to give a handwriting sample, and refused, she said, because the F.B.I. already had one in its possession. ''I felt grand juries were illegal and coercive,'' she said. For refusing to testify, she was jailed for seven months, and she and Mr. Ayers married during a furlough.