David Bowie’s revolutionary career is that he has bent rock & roll convention in so many imaginative and contradictory ways during the last quarter century that he has left many pop observers asking themselves if he was ever really a rock & roller at all.

It’s one thing for an artist to move between musical genres – in Bowie’s case, from the radical art-rock edges of Ziggy Stardust to the anxious soul strains of Young Americans to the icy techno rock of Low. But this English singer/songwriter didn’t simply explore musical genres.