Recently I sat in on a master class given by the film-maker Luc Dardenne. He spoke of how viewers of his films should not assume they understood everything about the characters. As members of an audience we should never feel ourselves wiser than they; we do not have more knowledge than the characters have about themselves. We should not feel assured or certain about their motives, or look down on them. I believe this. I recognize this as a first principle of art, although I have the suspicion that many would not.