Images: Pro-lifers often use images of aborted babies to show that abortion kills human life. The thought is that if we show an aborted fetus that looks like a human, it makes our case. While I think images can make this topic more tangible, and while it can evoke an appropriate intuitive responses in us, I hate Facebook posts and memes that merely throw out this tactic because it has the potential to undermine the pro-life case.
That being said, I don't at all deny the power if images. They can create visceral responses within us, and they may help tap into our intuitive moral sense. In fact, images and testimony of abortion practices have changed many minds. One great example of this are the jurors and reporters who covered the Gosnell Case. What they discovered helped them to visualize the injustice that was being done. One of the newer innovations in pro-life tactics is to have free, mobile ultrasounds geared towards women seeking abortion. We understand that images of living, or dead children can help to sway an individual's opinion. However, we don't only seek an emotional position change. We want to be honest and consistent. Intuitions can be wrong and we want to back up our position with truth and reason. If we stick only with the images, our position can be undercut quite easily.
Feel Pain/Brain/Heart: Similarly, many Christians use the development of the heart, brain, or ability to feel pain as evidences of why we shouldn't abort. This runs into the same problems as images and makes me very uncomfortable to imply that the value of life should be related to anything beyond the fact that a fetus is a living human. There are points in the unborn's life where it has no heart or brain, and there are points in its life where pain can be felt and recognized in greater or lesser degrees. While these ideas may help to build appropriate empathy, using them as argument is problematic because it undermines the pro-life case we’re trying to make. Using these arguments may help us to create laws as to how late one can have an abortion, or it may help someone realize that a 20 week old fetus is really human - but it doesn't at all establish humanity. Using your opponent's criteria is dangerous because in agreeing to their terms, you're not holding fast as to where true value and humanity lie. You're giving in to shifting definitions and scales. So while I think these arguments can be helpful and can spark someone's intuition, it is only good as a precursor to a much more involved discussion.
Bible: The general principles drawn from the Bible are helpful in making a case against abortion. However, many Christians try to proof-text the Bible to death and make it speak directly on issues, like abortion, to which it never intended to speak. It takes a lot less work just proof-text something, and it brings a more authoritative voice to it as well. But if you don't use the verse in context (textual and cultural), you create bigger problems for your case.
I often see Christians use the Psalms as a proof text for life in the womb. The palmist says that he was knit together in the womb by God. But this verse creates some problems when used as a proof text.
1) it downplays the genre of poetry. One only need read one verse further to see the palmist say that God formed him in the depths of the Earth. It is cherry-picking to say that the Psalmist is making a scientific statement that he was valuable as an embryo in his mother's womb, yet ignore the fact that he then says he was formed within the depths of the Earth. This idea of being formed in the earth is an Ancient Near Eastern view - a scientific comment, if you'd like. It seems cherry-picked to take a thought we can use for our argumentation while throwing out ideas we don't like.
2) if we're using the Israelite conception of life, are we willing to accept The idea they had that life was contained in the father, then implanted in the mother (Hebrews gives us a glimpse when it says Levi was in the loins of Abraham). Does the pro-life position now argue that sperm should be protected? Does the position have to entail anti-birth control? Maybe it does. Are you ready to be consistent?
3) If you start a proof-text war, you open up the door to counter proof-texts. What do you do with the verses in the Pentateuch which mirror the value of life found in the code of Hammurabi (Exodus 21) rather than valuing life equally? The Israelite law followed other Ancient Near Eastern law codes in many ways, and often set up compensation for crimes based on social status, not innate value of the individual (e.g. women, slaves, children, etc). Israelite understanding of life seems to value a fetus as less if evaluated by our current standards. If the text aligns with social status, their law makes sense. If we’re using the text out of context, it is difficult for the pro-life position to justify itself in a sound manner. There is also a passage where Israelite, under God's law, can induce an abortion (Numbers 5). I'm fine with that because their understanding of procreation was not as complete as ours, and because like David's child with Bathsheba, the death was intended to be a judgment. Since we can do paternity tests today and know for sure the paternity of both parents, will pro-lifers agree that children born from an adulterous relationship can be aborted? They'd never say that! If you want to proof text on issues to which the Bible didn't intend to speak, then you have to deal with this as you seek to defend the life of the unborn.
But besides the misuse of the Bible, its use in general doesn't work for the abortion debate. It is a starting presupposition that most opponents won't accept since they're either non-Christian or liberal Christians who have a very weak conception of biblical authority - if they recognize it as having any authority at all. Use the Bible all day long to share the Gospel, but until someone's heart is transformed by the Gospel of Christ, trying to speak Christ's commands and values he gave to his disciples isn't going to be fruitful because the people you're talking to aren't yet his followers.
BAD METHODOLOGY -
Use of Birth Control: I'm not going to make any value statements here about the use of birth control in general. However, I do want to speak to most birth control that comes in pill form. Many of these pills have as a primary or secondary method of control, the prevention of implantation of an embryo. We only discovered this a few years into our marriage, as Catalina's doctor had only pointed out the primary method of the pill she was talking. If distinct human life objectively begins at conception, how can someone who is pro-life knowingly continue using birth control which kills life after this point? Just because you don't go into a clinic to have an abortion, and just because you don't know whether the secondary method kicks in doesn't relieve you of this responsibility for life, and hypocrisy of you refuse to change accordingly once you are made aware.
Inconsistency in Ectopic Pregnancies: I understand that most pro-life Christians will disagree with me on this one, but I think the majority of that disagreement will come because most people haven't thought through the logic of this for themselves. Discussing ectopic pregnancies is very difficult, and the stakes are high. However, if the Christian logic is that life begins at conception, then pursuing a course that purposefully takes a life is problematic. The Christian notion of maintaining morality even in the face of overwhelming odds or negative consequences supersedes our desire for pragmatic, more comfortable outcomes. As I know this is a very controversial claim, I have created a section discussing two aspects of ectopic pregnancies. The first shows how moral logic doesn't allow us to pursue the death of an embryo in an ectopic pregnancy, and the second softens the blow by exploring some research as to how ectopic pregnancies aren't nearly as doomed as we are often lead to believe. You can find that exploration here.
Pro-Life Before Birth: I've been pretty repulsed by American politics, especially as it pertains to the main pro-life party. Liberals often say that pro-lifers are only staunchly pro-life about before-birth issues. Sadly, I have to agree with that statement as a broad generalization. Our politics, compromises, refusal to call out evil, tribalism, and lack of empathy are a living testimony against our purported platform of "life." Christians excuse injustice and harshness to groups we view as threats (immigrants, Muslims, atheists, homosexuals), yet claim we love life. While a strong response to abortion is understandable if abortion is taking human life, the world's embracing of abortion to help women is also understandable. Why should we expect non-Christians to act like Christians?
Sadly, because Christians have responded to abortion with such ferocity, we have not only hindered discussion and the changing of minds, but our unmerciful condemnation of sexual sins makes abortion more thinkable than repentance for a lot of Christian girls. Who would run to the arms of their condemners? Where would they run when much of our resources goes towards lobbying politicians over the creation of women's shelters or financing adoptions? We the church have few places of refuge for those in need and we make the choice to abort far easier for many. Our poor, judgmental witness and our choosing to emphasize legislation over community make our lives one of the worst arguments against abortion.
1. The Foundational Question: What is killed in abortion?
2. How to Determine Value and Rights: What quality and types of qualities confer rights and value to an individual?
3. Justified Reasons for Taking Human Life: What justifies the taking of human life?
4. Unjustified Reasons for Taking Life: What reasons fail to justify the taking of human life?
5. Bad Christian Arguments and Witness: Common pro-life/Christian arguments and actions which can undermine the pro-life position.
6. Counterrebuttals: A response to significant objections to the pro-life arguments.