Why is it wrong to kill babies?

Most of us agree it would be wrong to kill the cute infant pictured here. But I want to know: “Why is it wrong to kill babies like this one?” If pro-choice advocates values consistency, then they must become either pro-life, radical animal rights activists, arbitrary bigots, or supporters of infanticide. Let’s look at some possible reasons one might have for thinking it’s wrong to kill an infant in order to see why this is the case:
Answers that make you a radical animal rights activist
If it’s wrong to kill the infant because he can feel pain, then it would not be wrong to kill most fetuses because they cannot feel pain. However, since cows can also feel pain at the same level as infants, it would be morally wrong to kill cows.If it’s wrong to kill the infant because he is born or can survive outside of the womb, then you can kill the fetus, who isn’t born and can’t survive on his own. However, it would be wrong to kill the cow, because cows are born and can live outside of the womb.
If these are the real reasons pro-choice advocates think killing infants is wrong, then to be consistent they must also impose the same legal penalties for killing infants upon anyone who hosts a backyard barbecue.
If it’s wrong to kill the infant because he is a born animal who is human, while a cow is of another species, then pro-choice advocates must explain why some born animals get special treatment and others do not. If they don’t have a reason, then pro-choice advocates are as arbitrary as racists who once said it is only wrong to kill a born animal that’s human and white.
Answers that make you pro-life or pro-infanticide

If it’s wrong to kill the infant because he is simply a member of the human species, then it would also be wrong to kill the fetus, since he, too, belongs to the human species. Therefore, pro-choice advocates must become pro-life and oppose legal abortion.If it’s wrong to kill the infant because he has rational thought or can reason like you or me, then pro-choice advocates are mistaken. Both fetuses and infants cannot act rationally, and therefore, if possessing rationality is what makes it wrong to kill a certain thing, then there is nothing wrong with killing infants who lack rational thought.
If it’s wrong to kill the infant because he has the potential to develop rational thought, then it would also be wrong to kill the fetus since he, too, has the potential to develop rational thought. Therefore, pro-choice advocates must become pro-life and oppose legal abortion.
If it’s wrong to kill the infant because many people dislike killing infants and would adopt them, then it would be wrong to kill fetuses because many people also dislike killing those humans and would adopt them. Therefore, pro-choice advocates must become pro-life and oppose legal abortion.
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A critic might object that it’s wrong to kill the infant because he is a human being, but it is not wrong to kill a fetus that is also a human being because no one has the right to use someone else’s body against her will. However, this would make it right for a woman to let her infant starve to death because she refuses to breastfeed or let her child use her body in anyway. For a more in-depth answer to this argument see this Life Report episode or this hour of Catholic Answers live.
Most professional philosophers agree that any reason that would make it wrong to kill infants would also make it wrong to kill fetuses. Bioethicist Peter Singer writes,
“The liberal search for a morally crucial dividing line between the newborn baby and the fetus has failed to yield any event or stage of development that can bear the weight of separating those with a right to life from those who lack such a right” (Peter Singer, Practical Ethics, 2nd ed., Cambridge: Cambridge University Press, 1993, 142).
Of course, instead of valuing the unborn as we value infants, Singer thinks infants lack a right to life just as fetuses do. If your pro-choice friend disagrees with Singer and thinks it is wrong to kill infants, maybe this little test can help him see that he should be equally concerned about killing humans who exist in the stage before infancy.
By Trent Horn