It was clear from 1998’s Mos Def & Talib Kweli Are Black Star that Mos Def had great potential. But it was Black on Both Sides—released the following year—that proved he was a once-in-a-generation talent. The title of his debut solo album is a bit of an undersell: After all, there are more than two sides to blackness, and Mos Def, who’d later take the name Yasiin Bey, disambiguates Black identity spherically and expansively, using a range of diasporic, emotional, and musical varieties for his mosaic. Black on Both Sides feels as premeditated and directional as any rap album ever; nearly every song has a specific theme, message, or topic. “Mr. N***a” illustrates racist discrimination through a series of vignettes; “Mathematics” cleverly uses a series of statistics to snipe through social issues; and “New World Water” dives into the politics and health risks of water scarcity. Even the more straightforward bar-fests feel intentional. “Hip Hop” pledges allegiance to the culture, with passionate lyrics over a triumphant beat from Diamond D, while “Do It Now” finds Mos rhyming in Spanish and enlisting Caribbean-flavored patois while matching the energy of guest-rapper Busta Rhymes. While his raps are always eloquent and pointed, Black on Both Sides also showcases the breadth of Mos Def’s talents. He sings “UMI Says” with tenderness and reverence as he pays homage to the wisdom from his elders, and resentfully murmurs over guitar licks on “Rock n Roll”—all the while assaulting white supremacy’s appropriation of Black art forms. He also lends co-production duties to several songs, teaming with former Nina Simone bandleader Weldon Irvine on the atmospheric Vinia Monica duet “Climb,” and with 88-Keys on the jazzy album-closing instrumental “May-December.” By standards that Yasiin would set in subsequent years, this is the most vibrant album of his catalog. On future records, he’d lean further into the rock ’n’ roll heritage he sees as Black birthright; experiment more with his vocals; and fully unsheath his wings with a smorgasbord of global sounds. But Black on Both Sides is as wonderful of a starting point as it gets.