ne Sunday evening early in the fall, Glenn C. Loury arrived at the Charles Hotel in Cambridge, Mass., where a group of distinguished black intellectuals, including Cornel West, Lani Guinier and Henry Louis Gates Jr., was gathering to discuss the Sept. 11 attacks. The Rev. Jesse Jackson, the keynote speaker, had flown in to talk about possible shuttle diplomacy with the Taliban. Loury, an economist at Boston University who first achieved prominence as one of the nation's leading black conservatives in the Reagan years, was there on a diplomatic mission of his own: to mend the rift that has long separated him from liberal blacks like Jackson. He knew he might elicit more than a few hostile glances. ''I've been trying to figure out who you were for the longest time,'' one woman said coldly when they were introduced, according to Loury. But he decided to brave it.

Shortly before the meeting, Loury walked into a conference room where Jackson was chatting with Gates. As Loury shook hands with Jackson -- a man he had taken to task in print throughout the 1980's -- Gates effusively praised Loury's book ''The Anatomy of Racial Inequality,'' which will be published early next month by Harvard University Press. In it, Loury makes a striking departure from the self-help themes of his earlier work, defending affirmative action and denouncing ''colorblindness'' as a euphemism for indifference to the fate of black Americans.

Jackson said to Gates: ''This man is smart. Whatever his politics, he's always been smart.'' When the conversation

turned to the Middle East, Loury sheepishly reminded Jackson of an article he wrote more than 15 years ago in Commentary attacking him for embracing Yasir Arafat.

''You probably don't remember the piece,'' Loury said.

''Oh, yes I do,'' Jackson fired back.

''I looked him in the eye,'' Loury recalled a couple of weeks later, ''and said: 'I really wish I hadn't written that. It was a mistake, and I really regret it.' Jackson didn't say anything directly in response to it, but during his formal presentation he made a point of singling me out. He said: 'To say that Glenn Loury isn't black because he disagrees with me, well that's just stupid. We can't afford to leave brilliant minds like that by the wayside.'''

The next day, Loury e-mailed Charles Ogletree Jr., the Harvard Law professor who had organized the meeting. ''I came close to not showing -- for a variety of invalid reasons that have more to do with my scarred psyche than with anything in the real world,'' he wrote. ''You should know that I was deeply gratified by my reception on Sunday. Jesse was very generous. (I guess my 'political rehabilitation' is more or less complete now!)''

''That meeting was the defining moment for Glenn,'' his friend Orlando Patterson, a Harvard sociologist, later said. Or, as another scholar put it to me, ''Glenn is finally able to walk into a room full of black people who don't all hate him.''

lenn Loury beamed as he told me this story in the backyard of his Brookline, Mass., home, where he lives with his wife, Linda, a labor economist at Tufts, and their two young sons. It was a crisp New England afternoon in early October; the leaves had turned a brilliant red and yellow. Loury's house -- listed, he notes casually, in The National Registry of Historic Places -- is a large Federal-style structure built in 1854 by Amos Adams Lawrence, a wealthy abolitionist.

Loury, 53, is a tall, stocky man with a high forehead and a graying goatee that seems to add little age to a face that will probably always look youthful. On this afternoon, he was wearing a sweatshirt that said ''Professor Man'' -- a superhero he invented to amuse his sons. At once polished and insecure, he rarely misses a chance to mention when someone important has found him ''brilliant'' or ''smart.''

The quality of Loury's mind has never been in question. What his critics have expressed doubts about is his judgment. His career as a public intellectual has been a long and occasionally reckless journey of self-discovery and reinvention, a dizzying series of political transformations and personal crises that have left him with more ex-friends than friends. He is both a genuine maverick thinker and a shrewd political operator, and therefore a source of fascination and bewilderment, even to himself.

Loury was reared by working-class parents on the South Side of Chicago, where the color line was an inescapable fact of life. He vividly remembers being chased by a group of white kids when he rode his bike across that line. Loury fathered two children out of wedlock while he was still a teenager, and he dropped out of college and got a job at a printing plant. But before his eight-hour night shift he took courses at Southeast Junior College, and from there he won a scholarship to Northwestern University, where he studied mathematics and economics. He did his graduate work in economics at M.I.T., under the supervision of the Nobel laureate Robert M. Solow.

In his 1976 dissertation, Loury pioneered the study of ''social capital'' -- the informal relationships and connections that, as much as money or brains, pave the way for success in the labor market. As long as whites enjoyed superior access to ''social capital,'' he predicted, racial inequalities would continue to plague American society long after the end of legal discrimination. Loury's argument, coming 12 years after the passage of the Civil Rights Act, had profound implications for public policy. For if racial inequality is grounded in something more diffuse, and less amenable to remedy, than legal discrimination, how can it be combated? Is it the responsibility of the government, or of black people themselves?

As America's inner cities fell prey to a scourge of violence, drug addiction and out-of-wedlock births in the late 1970's, Loury came to believe that the greatest threat to racial equality was no longer the ''enemy without'' -- white racism -- but rather the ''enemy within'': problems inherent in the black community. Unless this ''enemy'' was confronted head-on, he argued, blacks would fail to achieve lasting social and economic equality. This was not his only pointed challenge to what he called the civil rights orthodoxy; Loury was also a critic of affirmative action and an outspoken supply-sider, promoting solutions to ghetto poverty rooted in entrepreneurialism rather than government aid.

In 1982, at the age of 33, Loury became the first tenured black professor in the Harvard economics department. Despite his sterling qualifications, he immediately began worrying about what his colleagues -- his white colleagues -- really thought of him. Did they know how smart he was? Or did they think he was a token? Before long, he was on the verge of what he calls a ''psychological breakdown.'' As he remembers: ''I did not carry that burden well. One wants to feel that one is standing there on one's own. One does not want to feel one is being patronized.'' In 1984, he moved over to the John F. Kennedy School of Government, which had been assiduously courting him almost from the moment he arrived.

''Glenn had no doubt that he was smart,'' Patterson says. ''But I think he was always doubtful as to whether the economics department had hired him because of his Afro-American connections. It was that anxiety about what his colleagues really thought that led him to doubt the value of affirmative action.'' His criticisms of affirmative action reflected these insecurities, emphasizing the stigma it imposed on people like himself.

Loury seemed to relish his chosen role as a thorn in the side of the civil rights establishment. In 1984, he delivered a paper in Washington at a meeting of the National Urban Coalition. The room, Loury recalls, was full of movement veterans, including Coretta Scott King; John Jacob, the National Urban League president; and Walter Fauntroy, former chairman of the Congressional Black Caucus. In a speech calculated to provoke his audience, Loury began by declaring, ''The civil rights movement is over.'' Blacks, he argued, were at risk of being dragged down by problems that could not simply be laid at the door of white racism. The spread of a vast underclass, the poor performance of black students, the explosion of early unwed pregnancies among blacks and the alarming rates of black-on-black crime -- here was evidence, he said, of failures in black society itself. It was time, he said, for blacks to assume responsibility for their own problems; blaming racism for their ills might be emotionally gratifying, but it was also morally obtuse.

When he was finished, Loury recalls, Coretta Scott King wept.

Word of the brilliant, contrarian black economist from the South Side of Chicago traveled fast. Conservative magazines solicited articles from him; The New Republic published his thoughts on race under the title ''A New American Dilemma.'' He befriended William Bennett and William Kristol, his colleague at the Kennedy School. He sat at President Reagan's table at a White House dinner, and he socialized with Clarence Thomas. (Although the two no longer speak, Loury still keeps a picture in his office of himself with Thomas.) While his liberal colleagues were boycotting South Africa, Loury traveled there in 1986 on a trip financed by the white diamond magnate Harry Oppenheimer.

Loury's alliance with the right was rooted in part in his deep aversion to the intellectual conformity he felt the left imposed on black intellectuals; the right offered not only prestige, resources and acceptance but also, it seemed, the freedom to speak his mind. (He was also partly motivated, like many rebels, by seething class resentment: he says that as the son of a low-level civil servant, he felt ''contempt'' for middle-class civil rights leaders.) But during this period, Loury says, he continued to see himself as ''a race man.'' Unlike some other black conservatives, he never called for abolishing the welfare state, and he rejected the idea that America had finished paying its debts to its black citizens.

Loury says he wanted to forge an intellectual middle ground, but his willingness -- indeed, his eagerness -- to assail black leaders like Jackson and to align himself with the Reagan administration made him persona non grata in liberal black circles. He was called an Uncle Tom, a ''black David Stockman'' and a ''pathetic mascot of the right.''

''It seemed like a classic sellout case to me,'' remembers Patterson, who went 10 years without seeing Loury. Loury's Uncle Alfred -- a proud race man, a steelworker and the patriarch of the family -- thought I was basically selling out to the white man,'' Loury recalls.

The hostility of fellow blacks would eventually take its toll, but at the time Loury took pride in their scorn. While enjoying considerable patronage in the form of corporate consulting fees and grants from conservative foundations, he cast himself -- and was portrayed by his white conservative patrons -- as a brave dissident who rejected the ''loyalty trap'' of reflexive racial solidarity.

And yet in his personal life, Loury continued to feel the pull of race. At the same time as he was lunching with fellows from the American Enterprise Institute, he began to immerse himself in a black urban world much like the neighborhood in which he grew up. He started playing pickup chess on tabletops in Dudley Square, an African-American commercial district in Boston. There, his views on social policy were unknown, and he was welcomed, not ostracized, by working-class black men -- the kinds of men he had known on the South Side, the kind of man he nearly became while working at the printing plant. ''There was a feeling for me that I was really blacker than a lot of these liberal black intellectuals who were denouncing me as a traitor to my race,'' he remembers.

As a black critic of racial liberalism, Loury rose rapidly in Republican public-policy circles. In March 1987, he was offered a position as under secretary of education to William Bennett. On June 1, 1987, however, Loury's life veered off-track. He withdrew his nomination, citing ''personal reasons''; three days later, those personal reasons became public: Loury's mistress, a 23-year-old Smith College graduate who had been living, at his expense, in what Boston papers called a ''love nest,'' brought assault charges against him. (She later dropped all charges.)

Loury's meltdown had just begun. After the scandal, his trips to Dudley Square became all-nighters. He was staying out on the street until 2 a.m. and venturing into ''some really rough spaces.'' He began freebasing cocaine and picking up women, spending much of his time in public housing projects. ''It was pathological,'' he says. ''I was castigating the moral failings of African-American life even as I was deeply caught up in it.'' All the while, he managed to maintain appearances at Harvard -- according to colleagues, he was lecturing more brilliantly than ever -- and to keep his other life a secret from his wife.

''I was bridging the extremities of two worlds,'' he recalls. ''Nobody at the Kennedy School could have known about this other world, and nobody in that world where I was a familiar character because I came regularly with a pocketful of money could have imagined the sophistication and power of the society of which I was a part. So you achieve a kind of uniqueness moving back and forth between those worlds. It was fun. There was a sense of power. There was a real rush. You weren't just breaking the rules. Rules didn't have anything to do with you. This was new territory.''

In late November 1987, Loury was arrested on charges of cocaine possession. After spending several months in the hospital and in a halfway house, he was released, and in January 1989, his wife gave birth to the first of their two sons. Loury's Harvard colleagues implored him to stay, but the scandal haunted him. In 1991, he left for Boston University, which offered him a tenured position and a salary Harvard couldn't match. For the next year, he devoted himself to his research in theoretical economics, which had languished for years, and ''got out of the race business.''

Loury's conservative friends stood by him, and Loury remained loyal. During the Anita Hill hearings, he prayed over the phone with Clarence Thomas. In 1995, he founded the Center for New Black Leadership with a group of conservative black intellectuals that included his friend Shelby Steele, the essayist.

''We were fellow travelers, Shelby and I,'' Loury recalls wistfully. ''We were partners in an enterprise. We fancied ourselves men of ideas who had found our way to this position out of our willingness to break ranks. It's a lonely business, this black conservative stuff.''

In the wake of his arrest, however, Loury had experienced a personal transformation that was to have far-reaching intellectual consequences. Five months after beating his cocaine addiction, Loury was dipped into a pool of water at a ceremony in Dorchester, Mass., and was born again. He started going to church regularly and was, he says, ''getting caught up in the rapture of these services where people were falling out onto the floor.'' The people who forgave him his sins -- his family, his fellow churchgoers and his wife -- were black, and Loury did not fail to notice this. According to Patterson, ''Religion was Glenn's entry back into the black community.''

''The experience did nothing to my politics,'' Loury insists, but the ''processing of my own frailties'' that it engendered, that did have an effect. Now that he was among ''the fallen,'' he found it difficult to keep telling people -- his people -- to ''just straighten up, for crying out loud,'' as he had been for years. It struck him, he says, as ''unbelievably shallow, spiritually, and politically problematic.'' In one of the more revealing passages of his new book, he criticizes the way successful blacks sometimes develop an ''antipathy'' toward the black poor: ''If only THEY would get their acts together, then people like ME wouldn't have such a problem.'''

fter his brush with the law, Loury became increasingly alarmed by the right's punitive rhetoric on issues ranging from racial profiling to the criminal justice system and wary of the ways in which, as a black man, he was being used as a screen for an antiblack agenda. He was horrified by Charles Murray and Richard Herrnstein's 1994 book, ''The Bell Curve,'' a social Darwinist tract arguing that black poverty was rooted in inferior intelligence. He was even more appalled by ''The End of Racism,'' the lurid assault on ''black failure'' written by Dinesh D'Souza when he was a fellow at the American Enterprise Institute.

Not only did his conservative friends not share his rage; they were taken aback by it and tried, he says, to muzzle him. Commentary, which had welcomed Loury's writing in the past, refused to publish his critique of ''The Bell Curve.'' And though The Weekly Standard ran Loury's caustic review of D'Souza's book, it also published a lengthy response from the author. In 1995, Loury resigned from the American Enterprise Institute over its support of D'Souza.

In a column called ''What's Wrong With the Right,'' published in the January-February 1996 issue of The American Enterprise journal, Loury wrote that while ''liberal methods'' on questions of race were certainly flawed, ''liberals sought to heal the rift in our body politic engendered by the institution of chattel slavery, and their goal of securing racial justice in America was, and is, a noble one. I cannot say with confidence that conservatism as a movement is much concerned to pursue that goal.''

''The thing about Glenn is that he was always a race man,'' says Anthony Appiah, a Harvard professor of philosophy and Afro-American studies. ''I suspect that the Reaganites he was consorting with never really knew that.''

Loury's break with the right became final in the fall of 1996 during the battle over the California Civil Rights Initiative, also known as Proposition 209. Aggressively promoted by Ward Connerly, a black conservative member of the University of California's Board of Regents, Proposition 209 sought to eliminate race- and sex-based preferences in state contracting, hiring and college admissions. The Center for New Black Leadership wanted Loury, the group's chairman, to publicly endorse the referendum, the culmination of the right's efforts to ban affirmative action. Loury expressed tepid support for 209 but refused to lobby on behalf of it.

''We're the Center for New Black Leadership, and we will be leading no black people if we make this our issue,'' he told his associates. But the board disagreed, and Loury resigned.

A few days later, Steele phoned him. ''Where do you stand on race?'' Loury says Steele asked him. ''It's as if you're a racial loyalist here. I thought we all agreed.''

''No, Shelby and I didn't agree,'' Loury says now. ''I was always aware that, whatever I thought about race, I'm still black. Shelby's position. . . . '' Loury starts to laugh. ''I was about to say, Shelby's position was that we had to completely transcend race, though I can imagine saying those words, too. But my heart wasn't in them, whereas he really meant it. How could it have been otherwise? His mother was a white woman. His wife is a white woman. When he looked at his own children's racial identity and wondered about an oppressive world that would say to those children, 'Choose sides' -- a dilemma I'd never faced -- Shelby's angle of vision was really quite different from my own. So in all honesty, it was I who betrayed him, not he who betrayed me.'' The two men have not spoken since that conversation. (Steele declined to be interviewed for this article.)

Writing in The New Republic on the eve of the referendum's passage, Loury declared that it was ''flawed both in letter and spirit,'' and went on to excoriate ''colorblind absolutists'' and to argue that ''some 'discrimination' against whites'' may well be ''the inevitable -- and defensible -- consequence of measures to identify and limit discrimination against blacks.''

''There came a point when I couldn't look my own people in the face,'' Loury says, explaining his evolution. ''Everyone else had a place to go. Some would go to Jerusalem. Others would go to Dublin. You see the metaphor. Where would I go? I came back to Chicago and talked to my uncle about what I was doing. There was a reproachful look in his eyes, a sadness. He said to me, 'We could only send one, and we sent you, and I don't see us in anything you do.' Eventually I realized I couldn't live like that.''

So where did Loury end up? Not -- and this is what makes him distinctive -- as a traditional liberal. Despite his new appreciation of racial solidarity, Loury remains fiercely independent. His outlook today is an unclassifiable, pragmatic blend of entrepreneurialism, black nationalism, Christian faith and social egalitarianism. Though he has relaxed his opposition to affirmative action, he quibbles with the way it is practiced, recommending instead what he calls developmental affirmative action -- programs intended to improve minority performance while upholding common standards of evaluation. It's a lonely position that infuriates his former allies on the right without endearing him to black liberals like Henry Louis Gates Jr. and Cornel West, who recently threatened to resign from Harvard if Lawrence H. Summers, the school's new president, failed to issue a sweeping defense of affirmative action. The private Loury is as hard to pin down as the public intellectual: an affluent homeowner in a largely white suburb who retains a deep respect for the Nation of Islam; a churchgoer who jogs while listening to gangsta rap on his Walkman.

''The Anatomy of Racial Inequality,'' based on lectures he gave in 2000 at the Dubois Institute at Harvard, offers a bracing philosophical defense of his new views. Returning to an argument he first presented in his dissertation, Loury argues that blacks are no longer held back by ''discrimination in contract'' -- discrimination in the job market -- but rather by ''discrimination in contact,'' informal and entirely legal patterns of socializing and networking that tend to exclude blacks and thereby perpetuate racial inequality. At the root of this unofficial discrimination, he says, is ''stigma,'' a subtle yet pervasive form of antiblack bias. According to Loury, stigma explains why many white Americans, as well as some blacks, view the imprisonment of 1.2 million African-American men as a ''communal disgrace'' rather than as ''an American tragedy.''

Of course, Loury himself once perceived the plight of the underclass in similar terms. As he wrote in 1985, ''Whatever fault may be placed upon racism in America, the responsibility for the behavior of black youngsters lies squarely on the shoulders of the black community itself.'' In his new book, by contrast, Loury asserts that the miseries of the ghetto can ''only be seen as a domestic product . . . for which the entire nation bears a responsibility.''

For Loury's former friends on the right, he is guilty of nothing short of apostasy. Writing in National Review in 1999 ''with a heavy heart,'' Norman Podhoretz -- an ex-leftist who achieved eternal notoriety among liberals by publicly changing his mind -- accused Loury of ''having fallen, or perhaps deliberately leaped, into 'the loyalty trap' he once worked so hard to escape. . . . The loss to his fellow blacks, and to the rest of us as well, is incalculable.''

Loury's change of mind has been greeted by liberals with considerable skepticism. Loury's account of his defection was ''too pat to be true, especially for a man of Mr. Loury's considerable intelligence,'' Brent Staples wrote in The New York Times. ''Race-baiting, Willie Hortonizing and homophobia were part of the package from the start and actually in fuller use in the 80's than now. That Mr. Loury failed to detect a 'conservative party line' on race while cozying up to the Reagan administration -- and as a star on the conservative lecture circuit -- is simply implausible.''

It's a fair point. After all, Loury was always sensitive to the left's rigidities on race. Why did it take him so long to rebel against those of the right?

I asked him this directly, and he said: ''Why the 90's and not the 80's? I'm going to give you an honest answer. I'd say, You're dealing with a 35-year-old kid in 1983.'' It's not an especially satisfying reply. After all, this ''35-year-old kid'' was a tenured professor at Harvard. Loury's conversion narrative is compelling stuff, but there's something missing. The story fails to explain why he began to notice things that were perhaps there all along. It fails to explain how the disapproval of blacks went from being a badge of pride to one of shame.

You get the sense that the new Loury would just as soon not be reminded of the old Loury. As he admitted to me in an e-mail message, ''The ghost or shadow of the 'old' Loury follows me, and I can still detect people reacting to this presence.''

Though he has to a certain extent ingratiated himself with the black intellectual circles that once shunned him, the reaction of many blacks to his new incarnation remains one of caution. ''There are still people who won't forgive Glenn for sleeping with the enemy,'' Patterson says.

Loury's embrace of his black identity is striking and, to some of his black friends, a touch overeager. ''Glenn is into sports now,'' says Patterson, who formed a close friendship with Loury again in the mid-90's. ''He's into basketball. He's developed a sort of pride in things black, and a sensitivity about any negative comments made about the group. I became a little concerned when Glenn started listening to gangsta rap. I thought there was a little overcompensation involved.''

It's hard not to conclude that Loury's intellectual positions today reflect shifting personal needs as much as shifting intellectual convictions. As Patterson points out, ''Glenn had argued so powerfully against affirmative action that the shift in position struck me more as a signal to the black community that he wanted back in, rather than a strongly intellectual change of heart.''

Loury, for his part, doesn't disagree: ''I don't know if I want to concede the point to Orlando, that there's no intellectual substance to the change of mind. But I think that's a pretty astute observation on his part.'' Still, he says, ''as long as I can give a more-or-less cogent account of what the current position is, I don't worry about the insincerity problem.'' When I asked him why he constantly changes his mind, he fell silent, pounding his fist on his desk. Leaning back in his chair, he stared quietly at the ceiling. Nearly a minute passed. This was the first time I had seen him at a loss for words. ''There may be something in my personality that doesn't feel comfortable getting along,'' he finally said -- an answer that nicely omits his equally strong desire to belong.

The question of belonging, of course, is one that all public intellectuals face, but it weighs especially heavily on black intellectuals who write about race. If you're a white college professor, you can float half-formed ideas and say controversial things; that's what you're paid to do. To be a black intellectual in the race debate is to have an audience with expectations, even demands; an audience anxious to know which side you're on.

You might imagine that the ambiguities of the post-civil-rights era -- in which the problems may be clear but the solutions are not -- would reduce the pressures toward intellectual conformity, but Loury's career suggests that the opposite is true. Debates over affirmative action and reparations are often so polarized as to leave little room for iconoclasts. To dissent, on either side, means you may find yourself in a lonely place, your loyalty -- even your blackness -- in question.

Throughout our conversations, I had the odd sense that both Loury and I were after the same thing: an understanding of Glenn Loury -- or, more precisely, how the old Loury became the new Loury. He often talks about his past self as if he were someone else, as if the only thing the two Lourys had in common were a body. Loury has been through therapy, and he often talks like a classic analysand, putting himself on the couch and registering genuine bafflement at how he got there. ''Friends of mine sometimes have joked to me that the old Loury and the new Loury should have a conversation,'' he says, chuckling ruefully.

When you spend time with Loury, you feel that he's still sorting out his past, still trying to figure out what has led him away from and toward the embrace of his race. He is incredibly self-conscious, and yet all his introspection has failed to yield any answers that satisfy him. The day after I interviewed him for the first time, we were walking along Commonwealth Avenue, just outside his office. ''I feel like I spilled my guts yesterday,'' he confessed. ''But you know, what I said was something of a revelation to me too. Because parts of my life are still a blur to me. I don't have a coherent narrative yet.''

Adam Shatz is a writer who lives in New York City.