These three lines contain three separate rhyming pairs, and a different anthologist might turn this extract into six lines of varying length. If Bradley and DuBois followed their own rule, they would break mid-word—“professio-/nal”—because the final syllable actually arrives, startlingly, on the next line’s downbeat. In “Book of Rhymes,” Bradley argued that “every rap song is a poem waiting to be performed,” but the anthology’s trouble with line breaks (not to mention punctuation) reminds readers that hip-hop is an oral tradition with no well-established written form. By presenting themselves as mere archivists, Bradley and DuBois underestimate their own importance: a book of hip-hop lyrics is necessarily a work of translation.

As the Golden Age ended, hip-hop’s formal revolution was giving way to a narrative revolution. So-called gangsta rappers downplayed wordplay (without, of course, forswearing it) so they could immerse listeners in their first-person stories of bad guys and good times. Shakur and the Notorious B.I.G. created two of the genre’s most fully realized personae; when they were murdered, in 1996 and 1997, respectively, their deaths became part of their stories. (Both crimes remain unsolved.) As the anthologizers blast through the nineties (“Rap Goes Mainstream”) and the aughts (“New Millennium Rap”), their excitement starts to wane. They assert that the increasing popularity of hip-hop presented a risk of “homogenization and stagnation,” without pausing to explain why this should be true (doesn’t novelty sell?), if indeed it was. There is little overt criticism, but some rappers get fulsome praise—“socially conscious” is one of Bradley and DuBois’s highest compliments—while others get passive-aggressive reprimands (“Disagreement remains over whether Lil’ Kim has been good or bad for the image of women in hip-hop”). Perhaps the form of their project dictates its content. They are sympathetic to rappers whose lyrics survive the transition to the printed page; the verbose parables and history lessons of Talib Kweli, for instance, make his name “synonymous with depth and excellence,” in their estimation. But they offer a more measured assessment of Lil Wayne, praising his “play of sound” (his froggy, bluesy voice is one of the genre’s greatest instruments) while entertaining the unattributed accusation that he may be merely “a gimmick rapper.” Any anthology requires judgments of taste, and this one might have been more engaging if it admitted as much.

Jay-Z grew up absorbing many of the rhymes that Bradley and DuBois celebrate. He was born in 1969, and raised in the Marcy Houses, in an area of Brooklyn from which Times Square seemed to be “a plane ride away.” (Nowadays, some real-estate agents doubtless consider it part of greater Williamsburg.) “It was the seventies,” he writes, “and heroin was still heavy in the hood, so we would dare one another to push a leaning nodder off a bench the way kids on farms tip sleeping cows.” He was a skinny, watchful boy with a knack for rhyming but no great interest in the music industry, despite some early brushes with fame—he briefly served as Big Daddy Kane’s hype man. Besides, Jay-Z had a day job that was both more dangerous and more reliable: he says he spent much of the late eighties and early nineties selling crack in Brooklyn and New Jersey and down the Eastern Seaboard. He was no kingpin, but he says he was a fairly accomplished mid-level dealer, and though he hated standing outside all day, he found that he didn’t hate the routine. “It was an adventure,” he says. “I got to hang out on the block with my crew, talking, cracking jokes. You know how people in office jobs talk at the watercooler? This job was almost all watercooler.” Then, almost as an afterthought, “But when you weren’t having fun, it was hell.”

Early recordings of Jay-Z reveal a nimble but mild-mannered virtuoso, delivering rat-a-tat syllables (he liked to rap in double-time triplets, delivering six syllables per beat) that often amounted to études rather than songs. But by 1996, when he released his début album, “Reasonable Doubt,” on a local independent label, he had slowed down and settled into a style—and, more important, settled into character. The album won him underground acclaim and a record deal with the very above-ground hip-hop label Def Jam, which helped him become one of the genre’s most dependable hitmakers. He was a cool-blooded hustler, describing a risky life in conversational verses that hid their poetic devices, disparaging the art of rapping even while perfecting it:

Who wanna bet us that we don’t touch lettuce, stack cheddars forever, live treacherous, all the et ceteras. To the death of us, me and my confidants, we shine. You feel the ambiance—y’all niggas just rhyme.

Too often, hip-hop’s embrace of crime narratives has been portrayed as a flaw or a mistake, a regrettable detour from the overtly ideological rhymes of groups like Public Enemy. But in Jay-Z’s view Public Enemy is an anomaly. “You rarely become Chuck D when you’re listening to Public Enemy,” he writes. “It’s more like watching a really, really lively speech.” By contrast, his tales of hustling were generous, because they made it easy for fans to imagine that they were part of the action. “I don’t think any listeners think I’m threatening them,” he writes. “I think they’re singing along with me, threatening someone else. They’re thinking, Yeah, I’m coming for you. And they might apply it to anything, to taking their next math test or straightening out that chick talking outta pocket in the next cubicle.”

Throughout “Decoded,” Jay-Z offers readers a large dose of hermeneutics and a small dose of biography, in keeping with his deserved reputation for brilliance and chilliness. His footnotes are full of pleasingly small-scale exultations (“I like the internal rhymes here”) and technical explanations (“The shift in slang—from talking about guns as tools to break things to talking about shooting as blazing—matches the shift in tone”); at one point, he pauses to quote a passage from “Book of Rhymes” in which Bradley praises his use of homonyms. Readers curious about his life will learn something about his father, who abandoned the family when Jay-Z was twelve; a little bit about Bono, who is now one of Jay-Z’s many A-list friends; and nothing at all about the time when, as a boy, Jay-Z shot his older brother in the shoulder. (Apparently, there was a dispute over an item of jewelry, possibly a ring, although Jay-Z once told Oprah Winfrey that, at the time, his brother was “dealing with a lot of demons.”)

“Decoded” is a prestige project—it will be followed, inevitably, by a rash of imitations from rappers who realize that the self-penned coffee-table book has replaced the Lamborghini Murciélago as hip-hop’s ultimate status symbol. In his early years, Jay-Z liked to insist that rapping was only a means to an end—like selling crack, only safer. “I was an eager hustler and a reluctant artist,” he writes. “But the irony of it is that to make the hustle work, really work, over the long term, you have to be a true artist, too.” Certainly this book emphasizes Jay-Z the true artist, ignoring high-spirited tracks like “Ain’t No Nigga” to focus on his moodier ruminations on success and regrets. (The lyrics to “Success” and “Regrets” are, in fact, included.) Readers might be able to trace Jay-Z’s growing self-consciousness over the years, as his slick vernacular verses give way to language that’s more decorous and sometimes less elegant. In “Fallin’,” from 2007, he returned to a favorite old topic, with mixed results:

The irony of selling drugs is sort of like I’m using it Guess it’s two sides to what substance abuse is

Bradley has written about rappers “so insistent on how their rhymes sound that they lose control over what they are actually saying.” But with late-period Jay-Z the reverse is sometimes true: the ideas are clear and precise, but the syntax gets convoluted, and he settles for clumsy near-rhymes like “using it”/“abuse is.” For all Bradley and DuBois’s talk about “conscious” hip-hop, the genre owes much of its energy to the power of what might be called “unconscious” rapping: heedless or reckless lyrics, full of contradictions and exaggerations (to say nothing of insults). If you are going to follow a beat, as rappers must, then it helps not to have too many other firm commitments.

One day four years ago, Jay-Z was reading The Economist when he came across an article bearing the heading “Bubbles and Bling.” The article was about Cristal, the expensive champagne that figured in the rhymes of Jay-Z and other prominent rappers. In the article, Frédéric Rouzaud, the managing director of the winery behind Cristal, was asked whether these unsought endorsements might hurt his brand. “That’s a good question, but what can we do? We can’t forbid people from buying it,” he said, adding, slyly, “I’m sure Dom Pérignon or Krug would be delighted to have their business.” Jay-Z was irritated enough that he released a statement vowing never to drink Cristal again, and he started removing references to Cristal from his old lyrics during concerts. (He eventually switched his endorsement to Armand de Brignac.) In Jay-Z’s view, Rouzaud had not only insulted hip-hop culture; he had violated an unspoken promotional arrangement. “We used their brand as a signifier of luxury and they got free advertising and credibility every time we mentioned it,” he writes. “We were trading cachet.” (Actually, the book, not free of typos, says “cache.”)

It’s hard not to think about Cristal when Jay-Z insists that his lyrics should be heard—read—as poetry, or when Bradley and DuBois produce an anthology designed to win for rappers the status of poets. They are, all of them, trading cachet, and their eagerness to make this trade suggests that they are trading up—that hip-hop, despite its success, still aches for respect and recognition. It stands to reason, then, that as the genre’s place in the cultural firmament grows more secure its advocates will grow less envious of poetry’s allegedly exalted status.

Another great American lyricist has just published a book of his own: “Finishing the Hat” (Knopf; $39.95), by Stephen Sondheim, is curiously similar in form to “Decoded.” Sondheim is just as appealing a narrator as Jay-Z, although he’s much less polite. (While Jay-Z has almost nothing bad to say about his fellow-rappers, Sondheim is quick to disparage his rivals, subject to a “cowardly but simple” precept: “criticize only the dead.”) But where Jay-Z wants to help readers see the poetry in hip-hop, Sondheim thinks poeticism can be a problem: in his discussion of “Tonight,” from “West Side Story,” he half apologizes for the song’s “lapses into ‘poetry.’ ” And where Bradley and DuBois are quick to praise rappers for using trick rhymes and big words, Sondheim is ever on guard against “overrhyming” and other instances of unwarranted cleverness. “In theatrical fact,” he writes, “it is usually the plainer and flatter lyric that soars poetically when infused with music.” Most rappers are no less pragmatic: they use the language that works, which is sometimes ornate, but more often plainspoken, even homely. (One thinks of Webbie, the pride of Baton Rouge, deftly rhyming “drunk as a fuckin’ rhino” with “my people gon’ get they shine on.”) Maybe future anthologies will help show why the most complicated hip-hop lyrics aren’t always the most successful.

It’s significant that hip-hop, virtually alone among popular-music genres, has never embraced the tradition of lyric booklets. The genius of hip-hop is that it encourages listeners to hear spoken words as music. Few people listen to speeches or books on tape over and over, but hip-hop seems to have just as much replay value as any other popular genre. Reading rap lyrics may be useful, but it’s also tiring. The Jay-Z of “Decoded” is engaging; the Jay-Z of his albums is irresistible. The difference has something to do with his odd, perpetually adolescent-sounding voice, and a lot to do with his sophisticated sense of rhythm. Sure, he’s a poet—and, while we’re at it, a singer and percussionist, too. But why should any of these titles be more impressive than “rapper”?

In the introduction to “Finishing the Hat,” Sondheim explains that “all rhymes, even the farthest afield of the near ones (home/dope), draw attention to the rhymed word.” But surely rhyming can deëmphasize the meaning of a word by emphasizing its sound. Rhyme, like other phonetic techniques, is a way to turn a spoken phrase into a musical phrase—a “rhythmic argument,” as Jay-Z put it. Bap bap bapbap. Rapping is the art of addressing listeners and distracting them at the same time. Bradley argues in “Book of Rhymes” that hip-hop lyrics represent the genre’s best chance for immortality: “When all the club bangers have faded, when all the styles and videos are long forgotten, the words will remain.” That gets the relationship backward. On the contrary, one suspects that the words will endure—and the books will proliferate—because the music will, too. ♦