BOOK REVIEW : Providing a Lens to View Black Culture : BUPPIES, B-BOYS, BAPS & BOHOS: Notes on Post-Soul Black Culture<i> by Nelson George</i> ;HarperCollins; $20, 329 pages

While getting his hair cut in Brooklyn in 1991, Village Voice columnist Nelson George (producer and co-writer of the film, “CB4”) watched a teen-ager dart through the barber shop and into its back yard.

Policemen of various races soon arrived, and when they asked the barber whether anyone had just run into the shop, he said no. George volunteered nothing, then heard the youth say--after emerging from his hiding place and being admonished by the barber for “messing with people”--that a traffic cop had hassled him.

Haircut complete, George left the barbershop only to find the very same youth talking loudly and gesticulating wildly on the pay phone out front--a phone often used by a “crew of knuckleheads” responsible for at least some of the neighborhood crime. George wonders, thinking back on a friend who had been mugged in the area: Did I do the right thing?

“Summertime Blues” isn’t typical of the 80-plus articles collected in this volume, the vast majority first published in the Voice, for most are concerned with black music, especially soul and rap. It would be a mistake to categorize George as a music writer, however, for although that’s his specialty--he’s published books on Motown, Michael Jackson, and rhythm and blues--George uses music, indeed every subject he addresses, as a lens through which to view black culture.

That’s why “Summertime Blues” acts to some degree as a thumbnail sketch for “Buppies, B-Boys, Baps & Bohos”: It captures any number of the conflicts that black flesh, in this country, is heir to. George, on leaving that barber shop, didn’t know whether he should have reacted as a citizen, a blood or a journalist--whether he should have helped the police land their suspect, written off the episode to underlying white racism or filed the scene away for future professional use.

George, clearly, is interested in the conflicts and differences within black culture--hence the book’s title. Buppies, of course, are black yuppies, which is to say assimilationists; B-boys are the hip-hop artists and their followers, usually from the underclass; Baps are Black American Princes and Princesses, privileged African-Americans with an air of entitlement; Bohos, defined broadly, are black bohemians, defying black and white conventions alike.

George was one of the first journalists to write about hip-hop and it’s sub-genre rap, and he knows it from the inside. Rap, he writes, “crystallized a post-civil rights, ultra-urban, unromantic, hyper-realistic, neonationalistic, antiassimilationist, aggressive Afrocentric impulse reflecting the thoughts of city kids more deeply than the celebrated crossover icons Michael Jackson-Bill Cosby-Oprah Winfrey et al”; he’ll get no argument for that position.

George ranges widely in the Boho world as well. On Spike Lee, who has remained a Brooklyn homeboy and merchandising entrepreneur despite cross-cultural success: His “economic nationalism may prove to be his most enduring legacy.”

On playwright August Wilson: “Scenes evolve into operatic monologues in which a speaker . . . riffs in enchanted phrases Lester Young would love.”

On former Yankee Willie Randolph: the one and only time George pitched against him in a stickball game amid the projects of Brownsville, Brooklyn, Randolph hit the ball over a 16-story building. George remembers thinking at the time, “I hope he makes it to the major leagues. At least then I’ll have a good story to tell.”

The biggest disappointment in the collection is the article on Gil Scott-Heron. It’s a question of expectations: this reader, at least, was looking forward to George’s proclaiming Scott-Heron one of the most undervalued artists of the rock-and-roll era--which he is, for no one is better at putting dense, political lyrics to music (see, for example, “We Almost Lost Detroit,” “The Revolution Will Not Be Televised” and most famously “The Bottle”).

What we get here, though, is liner notes from a 1984 “best of” album, and it’s not one of George’s better efforts. In that it’s unusual, for George is generally interesting even when he’s off his game. One element missing in “Buppies, B-Boys, Baps & Bohos” is humor, but give George credit for noting that the percussive guitar riffs in Aerosmith’s “Walk This Way,” often borrowed by DJs in early hip-hop, “may be Joe Perry’s only contribution to world culture.”