Alright, so, RE: the reason why the creature was protecting Siobhan - very likely it didn’t want to end up in the hands of the Red Guard or let her end up in the hands of the Red Guard. It’s currently trapped inside her so her being captured is a bad deal for it as well.
Secondly, she has a sense of what the creature is feeling, enough to know that it’s inimical to her and lying to her even though she doesn’t know with exactitude what that plan is. It’s like Miles trying to translate what the wind says to him. He has the general gist.
Thirdly, evil is subjective. If something wants to kill me, eat me and then use my corpse for its own purposes then it probably has very compelling reasons of its own, but from my perspective it’s evil because it’s trying to do me harm.
A serial killer could have very compelling reasons (to them) to kill people and a very urgent desire to escape prison afterwards. But just because I’m not certain if they wanted to strangle me or slit my throat doesn’t mean I’m going to let them out on the basis of being uncertain as to their end goal.
I could be wrong! We could get a whole redemption arc for Amber. But based on what we know now? I highly doubt it.
Evil is observable and objective. The operational societal standard appears to ask: would a reasonable person conclude that the behavior is evil? If yes, the behavior is evil.
For example, the defense at the Neuremburg trials tried to argue that only Governments define crimes; so, if you work for a government or military, then you can not have committed a crime. In other words, if you have not been charged with murder according to your country’s laws, you can not have been said to be criminally liable for executions you carried out in the course of your duty.
Justice Jackson and the prosecution team demonstrated that this was not true: evil committed against others is objective, and international society will criminalize evil acts even when it is not a matter of explicit prohibition in the law. There are crimes against humanity and peace, for which no subjective belief will justify the crime.
It is true, but not contradictory, that any person incapable of knowing right from wrong is legally insane, and not liable for their crimes. But their actions are evil: we merely don’t judge and punish them in their insanity. Even the insane are captured, institutionalized, and kept separate from society. On the other hand, if the person is capable of knowing right from wrong, then they can reason, and it doesn’t matter if they would they subjectively call their actions good or bad: society sets the standard for evil, not the individual.
In this story, it might be argued that aberrants are insane (incapable of reason), but as an existential threat to humanity in this story, they are objectively evil.
I agree with you, but we’re arguing that from a sane, human perspective.
Humans would always classify something that seeks to do them harm as evil. From our perspective, an alien race that came down and wiped us all out would be evil. From a planetary perspective, though? They could be a cleansing force stopping a parasitic growth.
Different cultures/points of view could see things differently. For example cannibalism is evil and abhorrent to some (most!), but a spiritual tradition to the cultures which once practiced it. The death penalty is viewed as evil by some people, but a right and proper punishment by others.
Probably if the creature possessing Siobhan feels trapped it would feel righteous and justified in attempting to escape and use her body for its own self.
However, from her point of view (and I suspect the point of view of all sane sentient species!) it is an evil that must be contained.
Which was my original point, that I would consider it evil, even if it considered itself to be justified in its actions. It’s inimical to Siobhan’s continued existence.