How about the severely mentally disabled
If it's severe enough, I think this is a cultural question that could go either way, not an categorical evil. There are probably relatively good places in the Moral Landscape where this kind of thing is allowed. In the current culture, it would violate important Schelling points about not killing humans and such. Other things would have to change to protect against potential abuse, before this can be allowed.
If it's worth saying, but not worth its own post, then it goes here.
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