by Stephen Thomas ErlewineAppropriately for the only hip-hop group that's been active for 20 years, cutting records and touring during that entire time, Public Enemy has a long memory. Long enough to be self-referential, as the title of their 2006 Paris collaboration Rebirth of a Nation suggested, but 2007's How You Sell Soul to a Soulless People Who Sold Their Soul??? bubbles over with references to their past: the title alone is an elliptical throwback to "Who Sold the Soul" on Fear of a Black Planet, but there are scores of musical nods to their past here, from the heavy metal shred on "Black Is Back" to how "Between Hard and Rock Place" plays like one of the bridges on Fear of a Black Planet, or the It Takes a Nation of Millions samples on "Can You Hear Me Now." Far from being recycled, these quotes and allusions provide a history that Public Enemy builds upon here, either in the beats or the words. The indictment of gangsta rap on "Sex, Drugs & Violence" or the materialism on "Can You Hear Me Now" carry a greater weight because their past is reflected within the music, offering a reminder of how things have changed in 20 years. Smartly, Public Enemy never tries to run from their middle age, but this isn't stilted like New Whirl Odor. They subtly yet sharply change the productions, expanding their signature dense soundscapes and sometimes departing from it as well, as in the hardcore gangsta of "Amerikan Gangster." Even if it hardly sounds like hip-hop that reaches the charts in 2007, this is ferocious and vital as music, while Chuck D remains one of the greatest lyricists in either rap or pop, as well as one of the more incisive political commentators. And in this context, Flavor Flav loses any of the cartoonish trappings his endless VH1 reality shows have given him, and remains a potent source of comic relief. In that sense, Public Enemy is the same as they ever were, but what's remarkable about How You Sell is how PE grows and matures without abandoning their core identity, proving that it's possible to age as a rap group without turning into an embarrassment. And even if PE doesn't pack the same kind of commercial punch as it used to, it's hard to call an album this spirited and alive irrelevant.