That may be the law, but it's terribly unfortunate that it is the law. What about coming out of your mother's womb makes you so much more of a person? The fact that you're now breathing your own oxygen instead of depending on hers? I guess on that line of argument, Siamese twins are less human because they depend on each other. What if you had one Siamese twin who could live without his twin, but the twin can't live without him, and he decides, I'm tired of having this parasitic twin living off of me. Sure, he's just as conscious as I am, but he depends on me to live, so he's less of a person, and therefore, I have the right to dismember him. I don't think we'd be okay with that. So it can't be that being a parasite, in and of itself, means you're not a person. In fact, even if the parasite had the mental capacities of a newborn, I don't think it would be okay to kill it. So perhaps there's something else magical about coming out of the womb that confers personhood on a baby? If so, what might that be?