Photographs are not allowed at the New York Public Library’s exhibition about J.D. Salinger. You have to leave your cellphone outside the small jewel box room where the library has installed a smattering of what some might call artifacts and others might call relics (as that term applies to, say, slivers of the True Cross). You’re not supposed to document the show because J.D. Salinger would not have liked that. But of course, J.D. Salinger would have hated this whole enterprise.
