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I profoundly disagree. The children at the birthday party are victims, but there was no anger there – in fact, the opposite. Melanie is telling Mitch about her childhood, and the two are coming CLOSER together when the birds attack the children. She is expressing sadness about her childhood, but not anger.
And the body in the farmhouse – we know nothing about any “anger” there. And the children in the schoolyard? Where’s the anger? In short, I think this explanation is way off base.
I’m paraphrasing from Robin Wood’s wonderful book, HITCHCOCK’S FILMS. Basically, Wood says that the movie takes any possible explanation you can come up with for the bird attacks and disproves or denounces them. Hitchcock makes fun of some (“It’s the end of the world!” is the slogan repeated by the drunk), he shows many counter-examples for others (the repeated attacks on children deny the notion that the birds somehow punish), and he actually slaps the audience in the face for suggestion that Melanie is herself the cause.
The whole point is that there IS no explanation for the birds.
Hitchcock has done things like that elsewhere. Think of the shower-bath murder in PSYCHO. From Marion’s point of view (and the audience’s) at that point, there is no explanation for the murder – she’s decided to return the money and get over her moment of craziness, she’s taking a shower to cleanse herself, and WHAM! The murder comes out of the blue, it’s completely unexpected and inexplicable in terms of her story.
Similarly, the necktie murders in FRENZY. Cary Grant suddenly being kidnapped in NORTH BY NORTHWEST. And on and on. We (the audience) may later learn some explanation for these acts (like murderous psychoses or conniving espionage agencies), but to the characters/victims, these events are the sudden eruption of chaos in their normal lives.
So with the birds (except that the audience never learns any explanation.) The birds are chaos, the destruction of order, the psychotic and unexpected, that shatter complacency and every-day life. If you want a modern metaphor, the birds are like terrorist attacks (although filmed way before political terrorism as we know it.) They erupt upon the scene to cause chaos and destruction, they have no “meaning”, there is nothing rational or explicable about them.
Thus, the ambiguous end of the movie. There is no resolution, there can be no resolution. Life is fragile, and lived on the edge of the abyss, no matter how much we pretend that we have things well-ordered and predictable. Hitchcock reminds us that our lives can be shattered by forces beyond our control, beyond our understanding. The theme of THE BIRDS is even more relevant after the 9/11 attacks.
I find THE BIRDS to be Hitchcock’s most profound philosophical or metaphysical statement.