Both evoke the legacy of Du Bois, the great black educator. Yet their views differ. Mr. Marable says scholarship and social struggle cannot be separated and has joined with other academics and activists to form the Black Radical Congress, a new grass-roots political group. Mr. Gates, meanwhile, warns against the dangers of politicized scholarship.

The founding fathers of what we now think of as African-American Studies were acutely aware of the distinction between scholarship that is political and politicized scholarship. Writing in 1925, the illustrious black bibliophile Arthur Schomburg worried aloud about propaganda masquerading as scholarship: work that was ''on the whole pathetically over-corrective, ridiculously over-laudatory; apologetics turned into biography,'' work marred at its core by ''puerile controversy and petty braggadocio,'' work that ''has glibly tried to prove half of the world's geniuses to have been Negroes and to trace the pedigree of 19th-century Americans from the Queen of Sheba.''

The great black intellectual and activist W. E. B. Du Bois himself, writing in 1933, warned black scholars against ''whitewashing or translating wish into fact.'' Closer to our own time, the sociologist Orlando Patterson memorably warned against the sort of black studies programs that utilize the ''three P's approach -- black history as the discovery of princes, pyramids and pageantry.'' Such an approach, he argued, ''does violence to the facts . . . is ideologically bankrupt and is methodologically and theoretically deficient.''

Would that these eloquent warnings had been heeded. Today, scholars in the field of African-American studies struggle to agree on the most basic facts of our history. A vocal minority seeks the deepest truths about black America in cultish, outlandish claims about the racial ancestry of Cleopatra or the genetics of ''soul.'' It's within this turbulent context that questions about the relation between scholarship and activism inevitably arise.

Intellectuals like Schomburg and Du Bois thought that all scholarship about ''the Negro'' would be ''political,'' either implicitly or explicitly, given the fact that, as Schomburg put it, ''The Negro has been a man without a history because he has been considered a man without a worthy culture.'' That's why even Schomburg, a man who loved the library like life itself, argued for what he called an a priori ''racial motive'' in black scholarship, while Du Bois stressed that ''the American Negro problem is and must be the center'' of the scholarly concerns of the ''college-bred Negro.'' Since few, if any, colleges and universities offered courses that included content about African-Americans, they viewed the scholar's task -- and his gift to the broader culture -- as contributing to a political progress by establishing the worth of black culture in the court of academic and public opinion.

In truth, the ideal of wholly disinterested scholarship -- in any field of research -- will probably remain an elusive one. But it's one thing to acknowledge the political valence of even the ''purest'' scholarship; it's another to demand of it immediate political utility. The ideal of knowledge for its own sake -- what Robert Nisbet once called the ''academic dogma'' -- may be unfashionable, and even unrealizable; but it should command our respect all the same. For it remains the basic rationale of the university. The scholar who analyzes the 19th-century slave narrative and its relation to the sentimental novel shouldn't feel guilty because her research isn't directly aiding the cause of distributive justice.

But scholars are citizens, too, and if it is wrongheaded to demand political payoff from basic research, it would be equally untenable to demand that research be quarantined from the real-world considerations that weigh so heavily upon us. Elsewhere, I've called for departments of African-American Studies to join with historically black colleges and universities to establish sophomore and junior-year summer internships for community development (through organizations like the N.A.A.C.P. and the Children's Defense Fund) to combat teen-age pregnancy, so-called black-on-black homicide and the transmission of H.I.V.

Yet those who would enlist the academy in the cause of activism must confront the awkward fact that the political views of academics can no more be regimented than their scholarly opinions. In the socialist tradition, thoughtful work on the political economy of black America has been done by such scholars as Gerald Horne, Adolph Reed and Manning Marable, who urge us to rethink the basic institutions of Western liberal democracy. In a conservative vein, such black scholars as Thomas Sowell and Walter Williams have argued that the problems of black America must be addressed primarily through voluntarist means. Obviously, both positions cannot be correct, but you can't gauge their validity by the relative compassion or commitment of their proponents. Policy disputes must be subjected to intellectual analysis, performed without a thumb on the scale. And it would be bitterly ironic if a field that was founded upon a protest against exclusion should itself become fearful of pluralism, either intellectual and political.

A typically vanguardist form of scholarly vanity is, of course, to suppose that we have a unique purchase on political wisdom, beyond the reach of ordinary citizens. Yet in the case of African-American studies, the yearning for political potency is altogether understandable. Even as the academic field has become institutionalized, black America continues to suffer massive inequities that are the legacy of historical racism. To complicate the picture further, black America has itself become enormously fissured, with a widening abyss between a growing middle class and an increasingly isolated underclass. Unfortunately, many of our conventional traditional modes of analysis simply fail to engage the vexing nature of these class differentials. ''People don't care what you know,'' a street slogan has it, ''until they know that you care.'' But genuine progress will depend not just on caring more, but on knowing more.

Public policy issues can indeed be a central concern of African-American studies, as they are at Harvard, the University of Michigan, U.C.L.A., Columbia and elsewhere. They raise conundrums as challenging as any you'll find in the academy. Thirty years ago, no one predicted the current class divide in black America; and this class divide insistently raises questions to which there are still no satisfactory answers. How do we put our people to work? How do we expand the black working and middle classes? How do structural and behavioral causes of poverty interact and how can they be defeated?

These are among the pressing issues that public policy scholars must address if they are to generate the new analyses and policy recommendations we desperately need. But the crisis of black America can't be willed away by commitment alone. On the level of policy, of practical politics, it demands empirical and analytical rigor: in short, the stringencies of the academic dogma.

As W. E. B. Du Bois, himself a committed activist who never abandoned the life of the mind, once wrote, ''Let us not beat wings in impotent frenzy,'' but ''rather conquer the world by thought and brain and plan.''

Copyright 1998 The New York Times Company