IN HIS ESSAY on the uncanny, Freud tells the story of a young couple who move into a house in which there is a wooden table with carvings of crocodiles. “Toward evening,” he writes, “an intolerable and very specific smell begins to pervade the house; they stumble over something in the dark; they seem to see a vague form gliding over the stairs—in short, we are given to understand that the presence of the table causes ghostly crocodiles to haunt the place.” Something similar happened this past winter at the Palazzo Litta in Milan, a stunning Baroque building in which the Fondazione Nicola Trussardi