Why Viability Is the Least Plausible Definition of Personhood

Pictured: 20-week fetus near the age of viability. Image used with permission from Life Issues Institute.

20-week fetus. Image used with permission from Life Issues Institute.

Estimated reading time: 10 minutes.

When we make the Equal Rights Argument, pro-choice people tend to respond with an alternative definition of personhood, usually an attribute that they believe humans must have in order to be considered valuable persons, such as sentience, brain activity, self-awareness, or the ability to feel pain. Typically we respond to these alternative explanations with Timothy Brahm’s Zoo Shooting thought experiment, pointing out that these definitions make at least one of two mistakes: they either allow too many organisms into the equal rights community, like squirrels, or they allow too few humans into the equal rights community, like newborns.

But there’s one pro-choice explanation of personhood that is so arbitrary and ad-hoc that I tend to use a different approach, and that is “viability,” meaning the ability to survive outside of a uterus.

Whenever you hear a pro-choice person make this argument, you should start by clarifying that they actually mean what you think they mean. Pro-choice rhetoric can often be vague, so asking lots of clarification questions is important. As we’ve explained before, most pro-choice people are very concerned about stopping the government from restricting what people can and can’t do with their bodies. Sometimes when pro-choice people talk about how dependent the unborn is on the woman’s body, they’re not actually making a statement about whether or not the unborn has moral status; they’re arguing that a woman should be able to do whatever she wants with anything inside of her body, or at least refuse another person the right to use her body for life support. So start by asking a clarification question, like:

I want to make sure I understand you correctly. Are you arguing that the unborn isn’t a person because it’s dependent on her body, or are you trying to say that it doesn’t matter if the unborn is a person because women shouldn’t be forced to have their bodies used as life support?

If the pro-choice person responds that they were making the bodily rights argument, then I’ll be glad I asked and will then clarify whether they’re making a Sovereign Zone argument or a Right to Refuse argument and go from there. Go to EqualRightsInstitute.com/BodilyRights for links to all of our resources on responding to bodily rights arguments.

It’s less common, but occasionally when a pro-choice person brings up viability, they’re actually intending to make a biological argument that the unborn isn’t an organism. This confusion comes from a misunderstanding of the word “independent” in some definitions of organism.

However, if the pro-choice person clarifies that they were indeed arguing that the unborn isn’t a person because it isn’t viable, I’ll often explain the problem of squirrels and other animals that are viable, and then I’ll explain why viability in particular is the least plausible standard for personhood, despite how often it comes up.

I’ll illustrate my approach with a story of a dialogue I had with a man I’ll call “Luke,” with whom I spoke at Davidson Community College last year. Luke made the viability argument, although he added an unusually ad-hoc twist that I hadn’t heard before, so in this article I’ll explain Luke’s argument, how I responded, and what else I would have said if he didn’t have to abruptly leave for class.

Luke Makes His Argument

Picture: Josh Brahm talking to a student about viability at Davidson Community College

Josh Brahm talking to a student at Davidson Community College

I was standing in front of our poll table when Luke walked up to sign the poll. As I engaged him in a conversation, he explained that he’s pro-abortion-choice, primarily because he doesn’t believe that the unborn become valuable people until they become viable.

I said:

Josh: Yeah, I’ve definitely heard some pro-choice people say that viability is the thing that gives people value before. A lot of people draw other lines, of course, like having sentience, self-awareness, the ability to feel pain, and so on, but there’s something about viability that I think makes it a stranger line to draw than all of those other lines, which is that of all the lines you could have picked, you picked the only moving target. Babies who weren’t viable 30 years ago are viable now because our technology is improving.

And that technology continues to improve. Did you hear about the goat born from an artificial womb recently? Maybe one day we’ll have something like that for fetal humans who can be transferred to an artificial womb if they’re too young to survive as a premature baby, pushing the viability line even closer to the beginning of pregnancy than it already is.

Luke wasn’t convinced.  He replied:

Luke: Yeah, but you don’t know if the baby would always survive.

Luke’s point seemed like an attempt to say that because we can’t always know at an epistemological level whether or not a particular baby would survive the transfer, that this should cause reasonable doubt about the ontological value of any given child. In other words, Luke seemed unwilling to admit that a given viable fetus could have moral status unless we had 100% confidence that that particular baby would survive a delivery.

So I said:

Josh: What if we knew that we had a 100% survival rate, that we could save every single embryo transplant. How would that affect your views on abortion?

Instead of conceding the point, he dug his heels in and said:

Luke: There’s a difference between ‘natural viability’ and ‘artificial viability’ in that it shouldn’t matter that we have the technology that’s so good we could save them, what matters is what would happen to them if we didn’t have that technology.

Before Giving a Counter-Argument, I Confirmed That I Was Correctly Understanding His Argument

I was taken aback a little because I had never heard a pro-choice person make the argument that I thought he was making. So I used one of the practical dialogue tips that we teach in the Equipped for Life Course as well as this article from TimI rephrased what I heard him saying, but in my own words. This is an important technique because we often unintentionally misinterpret what other people are saying, so if we feed back what we hear them saying, ideally using different phrasing, it gives them a chance to point out any translation mistakes, and then we can avoid inadvertently straw-manning them.

Graphic used with permission by Credo Courses.

While I often use this dialogue technique, I try to always use it when I think I hear a pro-choice person make a particularly weak or ad-hoc argument (AKA constructing an argument unsupported by evidence in order to win). I want to give them the benefit of the doubt that they are actually attempting to make a stronger argument than it sounds like they’re making. They may prove me wrong, but it’s better to work backwards from a potentially strong argument to the actually weak argument they’re making as opposed to assuming they’re making a weak argument and then them clarifying that they were actually making a strong argument.

Sometimes I’m talking to a pro-choice person and it sounds like they are making a terrible argument, but after clarifying their position I realize that I simply misunderstood it, or they didn’t word it very articulately. Unfortunately, this was not one of those days.

Josh: Okay, let me tell you what I hear you saying and you can tell me if I got it right. I hear you saying that once a baby is viable it becomes a valuable person, and that you agree that theoretically we could have artificial womb technology one day that will effectively bring viability from 23-weeks or so down to the first month of pregnancy, but that you don’t think that would morally matter because those now viable four-week embryos would not be viable if it weren’t for that technology, so they’re not actually persons. That’s what I think you mean by distinguishing between “natural viability” and “artificial viability.”

I was hoping that Luke would say, “No, of course that’s not the argument I’m making. That would be a bad argument.” But instead he said:

Luke: Yup, that’s exactly what I’m saying! You’ve got it.

As soon as he said that, he smiled and shook my hand, saying that he needed to get to a class. I told him that I understood and didn’t want to get in the way of his class schedule, but that I really hoped he would come back to pick up our conversation during our two-day outreach because I had some thoughts about his argument. He said he might if he had the time, but unfortunately he never did return.

Although that was frustrating for me, throughout my time doing pro-life outreach I’ve come to accept the possibility of conversations ending prematurely. Sometimes students are intrigued enough by us that they’ll skip whole classes to hang out and talk, but not everybody chooses to do that, so we do the best we can with the time that we’ve got with these students.

This situation, however, was particularly frustrating because it felt like I ran out of time because I took the time to clarify his view before rebutting. A part of me wished that I had just moved straight to demonstrating the flaws of his argument so that he could have heard some of my counter-arguments before leaving. But by doing that I would have been at risk of straw-manning him. I did the best I could with the information I had at the time, and I think I made the right decision given what I knew.

What I Would Have Said Next

These are the first two pages on the inside of the ERI Outreach Brochure.

If Luke had stuck around, I would have started by responding:

It doesn’t seem like you’re consistent with these distinctions. You’re saying that this premature baby in my brochure at 24-weeks and six days is a person because she’s viable, but she’s only viable because of our artificial technology! That baby wasn’t viable 100 years ago. It seems like you’re arbitrarily drawing a line between present tech and future tech and saying that future tech can’t change personhood, but instead wherever viability is based on the tech in 2017 is where the personhood line should always be.

If Luke still didn’t budge, I would have made a judgment call about whether I had enough rapport to push him more firmly with a statement like this:

That is completely and utterly arbitrary, and I can’t understand a reason for drawing a line that is that arbitrary for any reason other than you stubbornly don’t want to change your mind about this issue, regardless of which view is more rational.

I might also consider explaining the other reasons why viability is clearly the wrong line to draw when trying to determine a standard for personhood that makes sense and isn’t arbitrary:

I think there are all sorts of reasons why viability is the wrong line to draw. As I said, it’s a moving target, so now you could have a pregnant woman with a viable baby getting on a transatlantic flight and land where there are no nearby hospitals where her baby could be saved if there were a complication, so now her baby is no longer viable, meaning that her baby lost its personhood at some point during this flight but could regain that personhood if she used her return ticket.

Trent Horn makes a similar point in his book Persuasively Pro-Life:

How does it follow that just because the unborn cannot survive where born people live they are not persons? Suppose Martians abducted Earthlings and put them on Mars, where they would immediately suffocate. What if the Martians defended their actions by saying that humans are not “viable” and so are not persons?

I’d also explain that drawing the line at viability won’t accomplish what the pro-choice person is probably wanting to accomplish, which is to preserve personhood for all born humans and merely define the unborn out of having an equal right to life. As ERI Teaching Fellow John Ferrer points out:

This definition would also rule out personhood for a toddler who has a weak immune system and can only survive inside a protective bubble. It seems obvious to me that a “bubble boy” should have an equal right to life, even though his life will have many hardships that you and I can’t experience.

We should do our best to be charitable to our pro-choice friends, and interpret their arguments charitably. We should even acknowledge when they make an interesting or reasonable argument, and there are some pro-choice arguments that make some sense. I don’t agree with them, but I can see why other people do. The viability argument for personhood is no such argument. Pro-choice people would be wise to move on from it and find a stronger justification for their views.


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The post “Why Viability Is the Least Plausible Definition of Personhood” originally appeared at the Equal Rights Institute blog. Subscribe to our email list with the form below and get a FREE gift. Click here to learn more about our pro-life apologetics course, “Equipped for Life: A Fresh Approach to Conversations About Abortion.”

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Josh Brahm is the President of Equal Rights Institute, an organization that trains pro-life advocates to think clearly, reason honestly and argue persuasively.

Josh has worked in the pro-life movement since he was 18. A sought-after speaker, Josh has spoken for more than 23,000 people in six countries and in 22 of the 50 states.

Josh’s primary passion is helping pro-life people to be more persuasive when they communicate with pro-choice people. That means ditching faulty rhetoric and tactics and embracing arguments that hold up under philosophical scrutiny.

He has publicly debated leaders from Planned Parenthood, the National Abortion Rights Action League (NARAL), Georgians for Choice, and one of the leading abortion facilities in Atlanta.

Josh also wants to bring relational apologetics to the pro-life movement. “Some pro-choice people will not change their mind after one conversation on a college campus. Some of them will only change their mind after dozens of conversations with a person they trust in the context of friendship.”

Josh is formerly the host of a globally-heard podcast turned radio/TV show, Life Report. He now hosts the Equipped for Life Podcast. He’s also written dozens of articles for LifeNews.com and the ERI blog.

He directed the first 40 Days for Life campaign in Fresno, resulting in up to 60 lives saved.

Josh has been happily married to his wife, Hannah, for 15 years. They have three sons, Noah, William, and Eli. They live in Charlotte, North Carolina.

David Bereit, the National Director of 40 Days for Life, sums up Josh’s expertise this way: “Josh Brahm is one of the brightest, most articulate, and innovative people in the pro-life movement. His cutting-edge work is helping people think more clearly, communicate more effectively, and — most importantly — be better ambassadors for Christ. I wholeheartedly endorse Josh’s work, and I encourage you to join me in following Josh and getting involved in his work today!”

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