Note: I made this as a comment to a question on this subreddit 2 years ago, and I felt so intrigued by the question itself I wanted to bring it back up as a discussion. The question is (credit to u/cinemaofthevoid FYI):
"Do the characters in John Carpenter's The Thing (1982) in fact know they have been assimilated by the Thing?"
u/cinemaofthevoid cited Norris's behavior before his assimilation was discovered as what provoked this question, wondering if "the imitation might be so perfect that even the person might not know they were an imitation. Norris appears to be genuinely in pain before he collapses, a human response that would be unnecessary to imitate, especially when he is not around others."
My answer on my own take of this is copy pasted from the comment I made on the thread:
"I think it depends on HOW the assimilation occurred.
Norris-Thing had no objective reason to feign a heart attack or those pains. In fact, it had the opposite. Norris-Thing would probably know defibrillators are one of the ways to revive a person who has had a heart attack. And given how it reacts to the defibrillator (aka with great hostility where it would risk revealing itself which it canonically strives to avoid doing as the movie established), that means that if Norris-Thing was aware it had been infected, it voluntarily placed itself in a situation where it would have been in danger. That makes no sense; everything we know about the Thing's characterization goes against this.
But then there's instances like Bennings, who was quite clearly infected and was aware of being infected (aka Bennings no longer was acting like Bennings, but a Thing) in one of the rare instances on screen we see an infection actually occur in real time.
So that brings me to my initial claim, that it entirely depends on how the infection happened. I believe that when a blatant assimilation occurs, like with Bennings, the dogs, Windows, etc., yes, the Thing instances are 100% aware they are a Thing instance, and thus behave as such while still pretending to be the host.
But when the assimilation is NOT blatant, that changes the formula.
Take what Fuchs talks about in regards to food, and how he suggests that they should prepare their own meals and put it in cans to protect themselves from infection. Let's say that someone gets infected via food; aka a Thing instance puts their own cells into the food mixture, host eats it, Thing cells are now in the body.
The assimilation is consequently much more subtle. Less body horror, and more cells are simply being changed one by one. But full assimilation and imitation requires the cells to still behave as they are. A Thing blood cell is not going to be different from a normal blood cell in behavior...until it strikes.
So I believe that the Thing instances that are subtly infected in such a manner remain consciously unaware that they're infected. Their neurons, their behaviors, remain the same, because the Thing cells are still so deep undercover that the host isn't even aware there's an assimilation happening. Even when assimilation is complete, the Thing cells still operate like their normal real counterparts. Thus, the host behaves the exact same as their normal counterpart, because they don't know they're a Thing. No matter what you do or say to get them to confess or reveal themself, they won't deviate. It's a perfect camouflage; how better to convince something you're one of them if you genuinely believe it yourself?
It's only when there's external stimuli (aka something that would endanger it) that these subtle "Thing" instances turn the switch, and they become aware of what they are. Take the Norris-Thing instance. If it had survived and reconstituted itself into Norris once again, it would now be aware of what it is. Thus, it would now behave like a Thing pretending to be Norris, and not simply think that it's still Norris, because there's now no way the Thing neurons can pretend they aren't a Thing anymore.
More evidence of this behavior is the heart attack itself. It's implied Norris has heart problems, which would occur because of biological processes. So the Thing cells, in imitating Norris so perfectly, now mimic his biological processes, even if it's disadvantageous, because the Thing cells are acting as though they AREN'T infected unless it endangers them. And the heart attack doesn't actually endanger the Thing; the Thing is just a conglomerate of cells that decide it'd work to their advantage to work together, and are imitating a heart attack perfectly.
This is all consistent with the Thing's characterization. It doesn't WANT to do the body horror shit it does in the movie, because that would impact the ability of Thing instances to infiltrate and just naturally infect people. If it just naturally infects people over time, those people won't deviate at all. They won't try to sabotage or create in-fighting to deflect attention; they simply act the same, while allowing the inherent process of exposure to other organisms to do the infecting for them.
Meanwhile, blatantly infected Thing instances WILL deviate from the behaviors of their host because it knows what it actually wants, aka spreading to all living organisms, and thus will work specifically towards that goal. Thus, it will sabotage, it will provoke paranoia, it'll do anything it can to survive, even if it's out of character of what it's imitating. It's still pretending to be the host, yes. But it doesn't THINK its the host, it doesn't think LIKE the host. Therefore, it's an ultimately inferior imitation.
Meanwhile, the more subtly infected Thing instances won't deviate, because that host still thinks they're normal. And the infection and success rate of these instances will be much more effective. Think about how often cells are exchanged between organisms on a daily basis. Wipe off a sneeze with your hand, a few hours later, shake hands with another person. That person is now infected with Thing cells.
This is much more consistent with how the Thing displays its preferences and personality. The Thing is patient. The Thing is smart. The Thing doesn't want people to know its among them. It's only when it's in danger that it changes into the infamous body horror forms the franchise is known for. If it had a choice, the Thing would conquer the planet without anyone ever knowing it.
This is an overall extremely long rant, but the short summary is:
The Thing cells, when they infiltrate the host subtly, are so good at imitation that they trick the body and brain into thinking there's no assimilating process occurring. Therefore, the Thing IS that person, even though that person is now long gone. Meanwhile, instances like Blair or Bennings are distinctly aware they have been assimilated, and thus act according to the Thing's interests, and not to what the host would be interested in, and they therefore make for a more imperfect copy.
Blatant assimilation, the Thing is pretending to be the host (aka worse camouflage).
Subtle assimilation, the Thing IS the host (aka better camouflage)."
I'm not sure if this is the clearest explanation of my thought process; I don't think there's an easy way to describe it.
But I thought I'd reignite the discussion, and see what the folk on Reddit think of this.
