I’ve just watched Persona, making it the 12th Ingmar Bergman film I’ve seen (after Autumn Sonata, The Silence, All These Women, Cries and Whispers, Wild Strawberries, Summer with Monika, Smiles of a Summer Night, The Virgin Spring, Through a Glass Darkly, Winter Light and The Seventh Seal—in that order). And it’s the most difficult. Some critic has said, if Wild Strawberries is the most plagiarised Ingmar Bergman film and The Seventh Seal is the most parodied, Persona is the one most written…