> I also don't really agree with this definition either. This train of logic leads to the justification of euthanizing less intelligent humans.
How so? less intelligent humans have cognitive ability so they have rights.
> It also doesn't adequately address why a human with microcephaly or no frontal lobe has rights, but a dolphin or octopus or killer whale does not.
The question is not why the law is the way it is but the way that it should be. As it is now, It has rights because it is a human, we make our laws for ourselves and sometimes for other species, and I would definitely say that animals should have protections/rights (and they do). A law is also a custom or an enforced custom and certainly animals have customs. At least in america, many families take the toll of taking care of their family members with many deformities. the state should not enforce termination of these, but it should be optional for those that do take this unfortunate toll in their hands. (criminalization != decriminalization)
> It also allows for the justification of cruelty against animals who can feel pain but aren't intelligent enough to pass some arbitrary test of intelligence.
On the contrary, as a cognitive animal capable of pain. it indicates that you should not do so, I would say the capability of pain is the most important aspect to life. given that it is usually an indicator of the will to live.
> To be clear, I don't know the answer, I am hesitant to label anything as "innately valuable". I think that there is however a sliding scale of what is "ethical".
Neither do I. Abortion is euthanasia, and it certainly has merit. both economically speaking and in the sense of well being for humans. Given that human childbirth is probably one of the worst around on the animal kingdom.
It would be nice if we just relegated pregnancies to artificial wombs, but until the technology is there. I guess we'll be having this abortion "debate" forever.