Often abortion-choice advocates say the unborn might be a human, but it’s not a person. When asked what’s the difference between a human being and a human person, they typically cite one or more of the following characteristics.
You can remember them with the acronym SLED: Size, Level of development, Environment, and Degree of dependency.
A two-month-old is smaller than a twelve-year-old. Can we kill her because she’s not as big as a teenager? No, because a human being’s value is not based on their size. In the same way, the unborn is smaller than a two-month-old. If we can’t kill the two-month-old because she’s smaller, then we can’t kill the unborn because she’s smaller either.
A four-year-old girl can’t bear children because her reproductive system is less developed than a fourteen-year-old girl. That doesn’t disqualify her from personhood. She is merely less developed than older human beings. In the same way, the unborn is still a person, just at an earlier stage of development.
Whether you’re in a cave, in the ocean or on the moon, where you are has no bearing on who you are. How could a 7-inch journey through the birth canal magically transform a value-less human into a valuable person? Nothing has changed except their location.
Newborns and toddlers still depend upon their parents to provide nutrition and a safe environment. Can a mother kill her newborn son because he depends on her body for nutrition? Since the unborn depends on his mother in the same way, it’s not reasonable to disqualify his value either.