I want to be careful not to equate the artist with the work (always dangerous; see: "Genie, you're free") -- but Madlib is not a man, he is a genre. He is a philosophy. He is not an old head, he is the godhead, the platonic ideal of the crate digger. Somewhere there exists Otis Jackson, a man; I do not know him. What I know is the great current of sound that flows through him, the decades of music, produced in monk-like solitude, equally likely to remain hidden in an obscure side project or define an era. (Or, say, spur Kanye toward his last great verse.) For a long time, I thought Madlib's masterpiece was Madlib Medicine Show, a 13-volume series spanning everything from Detroit boom-bap to Brazilian prog-rock. The majority of its contents are too arcane, too generous to even be found online. And yet here, in winter 2021, comes Sound Ancestors, in which Four Tet emerges from the dusty, Borgesian library that is Madlib's vault with something of a guided tour. Is it Madlib's masterpiece, or merely an entrypoint? Either way, it's got "Loose Goose" on it. That feeling coruscating down your spine is called gratitude.