This is the tale of a thorny idea, and whether its time has come. The furor began in the hallowed corridors of academe and has gone on to involve some of the nation's leading social scientists.

The argument revolves around whether economic opportunities for black Americans now are shaped more by class than race. And some say the fallout could dramatically touch those who don't keep up with shifts in percentile income or demographic distinctions.

One side fears the idea's acceptance could wipe out affirmative action and anti-discrimination programs. The other embraces the idea, feeling the gap between the black haves and have-nots is widening.

And the man who has fueled the current dispute is William Julius Wilson, the pipe-smoking, new chairman of the sociology department of the University of Chicago, with his book, "The Declining Significance of Race."

Class and race, interviewed and debatable elements in whether Americans "make it" or fall by the wayside, played a key role in the life of Wilson, who struggled to escape the poverty of eastern Pennsylvania's coal fields.

"My father died when I was 13." recalls the 42-year-old "cholar, who grow up in Daird-town, about 50 miles east of Pittsourgn. "All we ever heard from our mother was talk of going to college," he says. "I made it and then served as a role model for my brothers and sisters.

"I know what it is to be poor. After my father died, we [the mother and six children] went on relief, what's called welfare now. But we didn't let that stop us from trying to improve ourselves."

Wilson's hunger for social mobility and excellence have taken him to his present chairmanship, a coverted position because of the department's high standing as a prime training ground for influental socialogists. Taking Sides

So now Wilson is embroiled in a controversy in which he contends that poorly trained and educationally limited blacks see their job prospects increasingly restricted to the low-wage sector, while talented and educated blacks are experiencing unprecedented job opportunities.

The result, he writes, is that "the recent mobility patterns of blacks lend strong support to the view that economic class is clearly more important than race in predetermining job placement and occupational mobility."

Scholars have lined up for and against Wilson in an unprecedented standoff among black intellecutals. Fourteen members of the 88-member Association of Black Sociologists voted recently to condemn the book as a "mis-representation of the black experience." claiming that attenting given it "obscures the problem of the persistent oppression of blacks." The group also expressed fear that the book may be used to shape government policy.

Wilson supporters say his theories don't mean that race is going out the window but that the sociologist is merely reflecting how increasingly fluid American society has become.

Recently, Wilson debated the idea at Michigan State Univresity with Charles Willie, professor of education and urban studies at Harvard, who charges that Wilson has isolated the "economic sphere from the other institutions and social arrangements of society."

Both claim they scored points in front of a predominantly student audience. But Willie had the reservation that most white students don't believe that blacks are discriminated against at white colleges.

Wilson, an indefatigable debater, is trying to stand up under the physical stress and emotional woes of constantly defending his ideas against intellectual heavyweights -- and bantamweights. For the last two months, under the rigors of travel and talking, he's been unable to shake a cold.

"It's becoming increasingly difficult for me to get up for debates," he says, puffing on his pipe. "I've turned down 10 invitations to lecture in the last two months. I'd like to do more writing and attend to more matters at the office."

But there are some speaking engagements be considers necessary. In March, four social scientists will discuss the book in a crities-meet-the-author session at the annual meeting of the Eastern Sociological Society in New York. That same month the University of Pennsylvania has scheduled a three-day conference on the question of class and race in black America. Willing and Ready'

Also, Wilson will speak at several southern black colleges in the spring.

However, like his favorite pro basketball player, Julius (Dr. J) Erving, Wilson likes one-on-one confrontations. "I am willing and ready to debate the issues publicly and I have been doing this for the last several months," he smiles. "And I've got to say I haven't seen a critticism of my book yet that I couldn't handle."

In his unassuming, quiet fashion, Wilson sees himself as a spokesman but not the leader of a cause. "I feel the need to spell out the issues I raised in my book," he smiles. "But I don't feel I've had a need to lead a fight. Sometimes I'd like to go back in the four rooms of my office and write."

A principal antagonist of the Wilson idea is eminent psychologist Kenneth B. Clark, a man active in the intellectual marketplace two decades before Wilson started his career and whose ideas gained international attention when they were used by the U.S. Supreme Court in its 1954 decision outlawing racial segregation in the nation's public schools.

The two were schedule to debate in October, but Clark had to leave the country for another engagement. Earlier, the psychologist had outlined his opposition in a New York Times op-ed page piece in March.

Wrote Clark: "The belief that class is now replacing racial distinctions in the present stage of the civil-rights struggle seems to be supported only by the fact that a pitiable few number of blacks are permitted to compete with whites for higher status positions."

The upward mobility of blacks, Clark continued, is dependent on the benevolence of whites who control special uplift programs.

"No black can yet be sure that he is being seen, evaluated and reacted to in terms of his qualities and characteristics as an individual rather than categorized and stereotyped as part of a rejected group," Clark wrote. "Until this is a fact, then racism dominates class achievements in spite of the wishful thinking of black and white liberals, social workers and social scientists."

However, Wilson has his supporters. Nathan Glazer, professor of sociology at Harvard, says, "I think it's an important book. Some people oppose it because of their emotional investment and the historical factor. Suppose you were to tell Jews that they were killed in Europe because they were capitalists.

"No one is making the claim that race was not important for the past, but things are changing. Wilson's book looks at the present and the future. These are not things that haven't been said before. It is the first time a black social scientist has said them with such strength.

"Of course there is a class-race interplay here which is complicated." Not Far Enough

Another supporter is William Sampson, professor of sociology and urban affairs at Northwestern University, who says the book was "pretty much on the mark and close to what I said in an article three years ago."

But Sampson doesn't think Wilson went far enough.

"Class is more important than race." he continues. "That's given. But what about the questions of whether class differences have behavioral significance for blacks? Or does this mean the establishment of a permanent black underclss? Or what kind of animosity exists between the black middle class and underclass? What kind of role models will young blacks have.?"

Wilson knows firsthand the need for role models. His aunt, Mrs. Janice Wardlaw, a retired psychiatric social worker in New York, filled the requirement.With her encouragement, he went to college and helped his brothers and sisters do the same (all six children have since earned at least a bachelor's de gree).

As a youth, Wilson spent his summer in New York with Wardlaw, who has two master's degrees. She recalls: "The very year that Billy finished high school I asked him to come live with us. I used to take him to my office and introduce him to people. My husband introduced him to boy souting and I took him to museums.

"He and I used to talk a lot about history. I encouraged him to study sociology or political science."

So Wilson has gone on to obtain degrees from Wilberforce, Bowling Green and Washington State, write three books and be named teacher of the year in 1970 at the University of Massachusetts. "The Declining Significance of Race" has won the American Sociological Association's Sydney Spivack Award.

Wilson has entered the middle class, but he denies the criticism that his chief concern is the middle class.

Looking out the window of his office past the ivy-covered ledge, Wilson takes a deep puff on his pipe and speaks in a deliberate cadence: "The real problem in the black community today is the poor, unskilled worker who is faced with unemployment and decreasing job opportunities...

"If people read my book carefully, they will find out that I say that blacks do experience discrimination regardless of their class positions, especially in the areas of housing and education.

"But to suggest that an educated black with a five-figure salary and driving his Mercedes-Benz has an experience similar to a poor black trappd in a ghet-to and confined to menial dead-end jobs is stretching the point a bit."

To the criticism that he has insolated the economic sphere from the rest of life, Wilson says he is contending that the economic factor has greater strength in intermining life chances.

Wilson maintains that not enough attention is given the poor and that the problems of the underclass cannot be addressed by anti-discrimination and affirmative action programs. He says discrimination and prejudice created the pool, who are particularly vulnerable to social change as society moves from a goods and service producing organism to automation and technology.

Wilson says one antidote is to create more jobs and guarantee full employment.

"We need to recognize that affirmative action and anti-discrimination programs are not enough," he explains. "They stop short. They don't deal with the concrete problems gripping poor blacks...

"No one ever said that race is insignificant. I certainly have never said that, but it's quite clear that there's a class factor that's operating."

Nvertheless, in the midst of the dehate over his book, Wilson realizes he can't go on interminably arguing his case.

"I'm going to be writing an introduction to 'Declining Significance of Race,' a new epilogue that will consider some of the criticism of the book," he says.

Meanwhile, he says, "I've got to go on to something else. I'd like to write a definitive theoretical general work, something in macro-sociology. That would be my magnum opus." CAPTION: Pictures 1 and 2, William Wilson, by John White