Scenarist Buck Henry says "This is where the audience lost it's bearings."
Nichols goes on to explain that no matter how strange, dream-like, and satirically abstract the film had been to that point (and 90% of the film is strange, dream-like and satirically abstract—taking place at a perpetual 2:00 in the afternoon), it is this scene where audiences finally said: "Nah, I'm not buying this." No matter how grief-stricken parents are going to be, they're going to recognize that Yossarian is not their kid. They've got to know.
But the point of it is: what difference would it make?
"It's one of those scenes—you either 'buy' it or you don't," says Nichols. "It either speaks to you or it doesn't. You know that story about Robert Frost reading his poetry to an audience? They're meant to ask questions and a woman says 'I didn't understand that last poem. Could you explain it?' And Robert Frost says 'You mean, you want me to say it again, but not as well."
The scene is pretty much verbatim what it is in Joseph Heller's novel, and runs along the borscht-belt twisted logic and Abbott-Costellian literalness that Heller brought to the justifications and rationalizations and bureaucratic SNAFU's of your basic war scenario, crossed with the cliches of Hollywood war movies. Here, the point is not that the family specifically needs to see their son, it's that they need to be made happy (or sad) that they flew all the way from New York, and got to see him before he died.
Now, if he was dead, that wouldn't make them happy, would it? So, Doc Daneeka needs to find a "live" one...even if it's not their son. Because it's not about the son, it's about the family and their feelings.
And in the Vast Scope of a World War, soldiers are interchangeable, anyway.
And it doesn't need to make literal sense because it takes place in that nether-fever-world between the time Yossarian is stabbed by Nately's whore and the time he wakes up, recovered, sequences bridged by the ever-expanding scene of Yossarian helping Snowden. It doesn't have to make perfect sense. It just has to make sense to Yossarian...and nothing makes sense to him. Not the war, nor his place in it. He is stuck in a self-perpetuating Möbius strip of a military tour—the world of Catch-22.
The Set-Up: In a scene in flash-back that Yossarian (Alan Arkin) recalls after Orr's (Bob Balaban) plane-crash, he is asked by Doc Daneeka (Jack Gilford)to impersonate a soldier who has already died for the benefit of his family (Richard Libertini, Elizabeth Wilson and Liam Dunn). If it seems dark, it's because Nichols and his Director of Photography David Watkin were reducing the f-stop on the camera lens throughout the entire scene.
Doc Daneeka: He's dead.
Yossarian: Who's he?
Daneeka: Nobody you know. He's just a kid from my hometown.
Daneeka: He died a few minutes ago. they came all the way from the States just to see him. Get in the bed, willya?
Daneeka: Look, his mother and his father and his brother flew all the way here. They know he's dying...
Yossarian: So what do you want me to do?
Daneeka: Be him.
Yossarian moves to leave...
Daneeka: Oh, just for a few minutes. Then they'll go away.
Daneeka: Yossarian, they came 5,000 miles just to see you before you die.
Yossarian: What are you talking about, I'm not dying!
Daneeka: Of course, you're dying. We're all dying.
Yossarian: But, Doc, they'll know! They came here to see their son!
Daneeka: They'll have to take what they can get. One dying boy is just as good as another. Or just as bad (chuckles).
Yossarian: Doc! It won't work!
Daneeka: Look! These people have come a long way and I don't want to disappoint them. I'm...I'm sentimental about old people.
Yossarian: But wha...what if they start crying?
Daneeka: They probably will start crying. I'll wait right outside the door...and if it starts getting sticky, I'll come in and break it up.
Yossarian (gets out of bed): It's not gonna work!
Daneeka: Do this for me and I'll do something for you.
Yossarian: Will you ground me?
Daneeka: I can't.
Yossarian: What do you mean? You can fill out a slip saying I'm on the verge of a nervous collapse and send it to group, can't ya?
Daneeka: Sure I can.
Yossarian grabs his face in joy and gets back in the bed.
Daneeka: But there's a catch.
Daneeka: Group has to approve my action and group isn't going to. They'll put you right back on combat status and send me to rot in the Pacific.
(A knock on the door)
Yossarian: Oh my God, here they are.
Daneeka: Start dying. Do this for me...and I'll send you to Rome on a five-day R and R.
Pa: He looks terrible.
John: He's sick, Pa.
Yossarian: My name is Yossarian.
John: His name is Yossarian, Mother. Yossarian, don't you recognise me? I'm your brother John. Don't you know who I am?
Yossarian: Sure I do. You're my brother John.
John: Pa, he knows me. Yossarian, look, here's Papa. Say hello to Papa.
Yossarian: Hello, Papa.
Pa: Hello, Harvey.
John: His name is Yossarian, Pa.
Pa: He looks so bad.
John: He's very sick, Pa. Doctor says he's gonna die.
John: Ma...his name is Yossarian. (John leans in)
John: She doesn't remember things too good anymore.
Yossarian: That's OK. She...she can call me Harvey if she wants to.
Daneeka walks in.
John: Don't worry, Yossarian. Everything's gonna be all right.
Yossarian: I know.
John: We came all the way from New York. We were afraid we wouldn't get here in time.
Yossarian: In time for what?
John: In time to see you before you died.
Yossarian: What difference would it make?
John: We didn't want you to die by yourself.
Yossarian: What difference would it make?
John: He must be getting delirious. He keeps saying the same thing over and over again.
John: It's not Harvey, Ma, it's Yossarian.
Ma: What difference does it make? He's dying!
Words by Joseph Heller and Buck Henry
Pictures by David Watkin and Mike Nichols
Catch-22 is available on DVD from Paramount Home Video.