Clinton, who is 81 years old, often punctuates a lesson with laughter. He’s prone to name-dropping: “Eminem, I’ve known him since 14, 15 years old,” or “Mos Def, I knew his parents,” or “Tupac and Digital Underground, we was already like that,” or “Prince, he was a baby Funk-eteer.” Sitting in a bright blue T-shirt bearing a comic-book seal with the names of his two transcendent bands—Parliament and Funkadelic—emblazoned at the midsection, Clinton presents as an apparition of sorts. The picture’s quite literally not believable.