Here, from the original script.
Couldn’t resist posting this. For those not in the know, Duvall is the surgeon, Grant the hero, and Michaels the villian.
INT. PROTEUS - AT WINDOW
Grant reacts as he sees a peculiar phenomenon: the big-bluish corpuscles which stream past the submarine are turning bright red the instant they impinge against the Capillary Wall. They keep moving on, in a constant flow, taking on their new color during:
GRANT: (amazed)Look at that...they’re changing color...
CORA: (thrilled) Doctor — is it possible? That we’re
seeing it happen before our eyes?
DUVAL:(quietly) Yes, Cora... We’re the very first to see
the living process.
They both look out, too deeply moved to speak. Atter a moment:
GRANT: Mind letting me in on what’s going on out there?
DUVAL: A simple exchange, Mr. Grant. Corpuscles releasing carbon dioxide — the moment they touch the Wall of
the Lung — in return for oxygen coming through
from the other side.
GRANT: Don’t tell me they’re refueling...
DUVAL (almost in a reverie)
Oxygenation...
Cora turns to look at him, feeling close in this shared moment. Grant, too, is moved by Duval’s manner. Michaels glances up from the Lung Map.
DUVAL: (still gazing out) We’ve known it exists —
even though we never saw it...like the structure
of the Atom... But to actually behold one of the
miracles of the Universe — the engineering of the
Cycle of a Breath...
He is too moved to continue.
MICHAELS: (into the silence) Nothing miraculous about it.
Just an interchange of gases. The end product
of five hundred million years of Evolution.
DUVAL: You can’t believe all that’s accidental? That there
isn’t a Creative intelligence at work—
Now, want to bet that Hollywood rewrites it so the religious fanatic is the murderer?
DUVAL: A simple exchange, Mr. Grant. Corpuscles releasing carbon dioxide — the moment they touch the Wall of
the Lung — in return for oxygen coming through
from the other side.
GRANT: Don’t tell me they’re refueling...
DUVAL: (Almost in horror) A greenhouse gas being created. We’ve known it happens, but we’ve never been able to prove it.
MICHAELS: It’s one of the least significant of the greenhouse gases.
DUVAK: You don’t believe in anthropogenic global warming? You see it before your eyes, that man is the source of it all!
There. The religious fanaticism has been upated.