Shortly after I saw Ingmar Bergman's Persona for the first time, I discovered the writings of R. D. Laing. Laing is a Scottish psychiatrist, blazingly humane, who is trying to understand (among other things) how madness becomes the sanity of the mad. A passage from his book The Divided Self might serve as epigraph for Persona:

The unrealness of perceptions and the falsity and meaninglessness of all activity are the necessary consequences of perception and activity being in the command of a false self—a system partially dissociated from the "true" self….

Bergman's film begins with an actress, young and successful, who has suffered these consequences. All activity has become false and meaningless to her. (pp. 13-14)

After the titles, the film slashes ahead with the swiftness that comes not from speed but from a superb power of distillation. Everything is lean, yet everything is rich. This we...