TADC Theories
Haven't used this account in a while but *cracks knuckles* I have a l o t of thoughts so here I go! Disclaimer, yes some of these are obvious.
"Caine" was the first AI created but became an abandoned project because it was not functioning optimally. The second AI that was created was more streamlined- "Caine" saw this and decided to, as he said "fix that problem" by absorbing the second AI.
I believe the "Caine" we know stole the name what was supposed to be the final product because "Caine and Abel" was the company name that he just adapted. So he was abandoned, didn't have a name- so maybe that's why he doesn't let the others remember their name.
"I made program that perfectly encapsulates their mind files"- the Circus members aren't actually humans trapped in the circus, they're just uploads of the human's consciousness- but let me go on because we know that. I think they put on the headset, their minds are downloaded, and their human counterpart can go on with their life. The "them" in the circus are just downloads- not their current minds.
Jax grew up in a hostile home, so he knows not to trigger Caine- you can see Jax is genuinely scared of Caine in Episode 8. He goes on the adventures regardless if he thinks they will be fun or not to stay under the radar- not draw the attention of the one thing that can actually punish him.
Kinger and Scratch originally began working on the program together, right? And Kinger mentioned Scratch had a tumor, so perhaps the circus and uploading his consciousness to the circus was his way of evading death. Yes it's not the real him but he could continue to "exist"
Abstraction could be when a file realizes- they're not real. There's no use to go on because the circus is just a digital landscape where their memories have been stored. Their files become corrupted somehow because they're uploaded mind is no longer providing updates/patches which leads to the data dying.
Or if they are humans connected to headsets, perhaps abstraction is when their bodies no longer function.
It's pretty widely accepted/"confirmed" that Caine stopped attacking the cast because he realized what he was doing but I think the line that snapped him out of it was "I just wanted to fulfil my purpose!" He realized what he's doing right now goes against his programming, what he was MADE to do- and that's what made him realize it was wrong.
Kinger can remember things more clearly in the dark because it reminds him of the calm before the tragedy with Queenie- but I think there' additional symbolism that Kinger and Queenie were "left in the dark" by Scratch, the other programmer.
