What is a fetus? The question is objective, not subjective. To determine the status of a fetus is not a matter of personal arbitrary caprice. The fetus is either alive or not alive. The fetus is either human, or not human. The fetus is either a person, or not a person. What I think the fetus is does not determine which of these it actually is. If a fetus is a living human person but I do not believe or think that it is a living human person, my thoughts have no bearing on what a fetus actually is. By merely thinking or believing I cannot change what is personal into a nonperson, what is living into unliving, or what is human into the nonhuman. By the same token, if the fetus is not a living human person, then whatever I believe or think cannot change it into a living human person.
— R. C. Sproul, from Abortion: A Rational Look at an Emotional Issue, p. 17