“To draw you must close your eyes and sing,” said Picasso, and the songs he sang with paper ranged from ditties to folk tunes to arias. Picasso didn’t simply put pencil to paper, he tore, twisted, and burned it in endless experimentation, sometimes using it to create 3-D forms. “Picasso and Paper,” organized by the Cleveland Museum of Art and the Royal Academy of Arts, London, brings together 300 of these works, embodiments of Picasso’s ever roaming imagination. —E.C.