I recently posted a simple argument against abortion for pro-choice advocates to consider. I challenged them as to how certain they were of their conclusions, comparing this to the certainty associated with applying the death penalty, and noting the dismay most people feel when someone who is on death row is exonerated.

I’d now like to examine the most common replies to the first premise: it is morally wrong to kill innocent human beings. Rejecting this premise seems the only possible defense against this argument, unless the humanity of the fetus is denied, an extremely dubious proposition.

But how can this premise be rejected? Isn’t it always wrong to kill innocent human beings? Certainly, the onus is on pro-choice advocates to find good reasons why this may not be the case. Innocent people are sometimes killed in war, but no-one thinks this is permissible, but rather deeply regrettable: deliberately targeting the innocent in war is morally wrong. There are two general approaches, and I’ll briefly examine them both.

Bodily autonomy

The first approach is to claim that in some situations, innocent human beings can be killed. Usually, these situations involve a reference to a woman’s bodily autonomy, and come in two forms. One is to argue that a women has sovereign control over her body, and can whatever she likes with anything within her body. This doesn’t seem to be true, as it doesn’t seem permissible for a pregnant woman to deliberately ingest a drug that will result in a deformed child. More generally, having sovereign control of a space doesn’t usually confer the automatic right to kill people who enter it, say our private property.

Judith Jarvis Thomson presents the more sophisticated version of bodily autonomy in her famous article ‘A defense of abortion‘. She constructs a rather bizarre analogy about someone waking up to find a famous, unconscious violinist plugged into their body. The violinist needs the use of their body for nine months to survive, and unplugging the violinist would kill him. Thomson claims the victim would be under no obligation to keep the violinist plugged in, and likewise a pregnant woman is under no obligation to continue providing life support for the fetus.

There has been a lot of ink spilled over Thomson’s argument, and debate among philosophers continues to this day. We cannot examine it in detail here. But it’s worth noting some important points. Firstly, the argument is controversial, and not even all pro-choice advocates agree it is a valid defense for abortion in all circumstances (e.g. Kate Greasley). For example, the violinist is attached involuntarily, but some philosophers contend that voluntarily engaging in sexual intercourse implies consenting to pregnancy, should it occur. Others claim a mother has special obligations to her child. Secondly, Thomson never intended her argument to mean abortion is permissible in all circumstances, especially late-term abortions. In fact Thomson notes that she is not arguing for the death of the fetus at all, but rather its removal, which currently inevitably means its death. Artificial wombs could change this. So Thomson’s reasoning isn’t a slam-dunk argument for rejecting the first premise of our simple argument against abortion.

Persons, not human beings

The second approach is to modify the first premise to remove the reference to human beings, replacing it with ‘persons’: it is morally wrong to kill innocent persons. Here,  person is a moral term, meaning an entity with certain rights, in particular the right to life. So the modified premise is really saying it is wrong to kill human beings who have a right to life. Because it is claimed that a fetus does not meet the criteria for being a person, it does not have a right to life, and consequently it can be permissibly killed.

Defining persons also occupies a lot of space in philosophy journals, but it usually involves possessing certain rational capacities such as being conscious and self-aware. Herein lies the problem for this approach: these definitions of person invariably exclude infants. If the ‘personhood’ approach is taken, it is implicitly granting that infanticide is permissible in addition to abortion. For most people, that’s a bridge too far. And if it isn’t, there are implications beyond infanticide.

Conclusion

So there we have it. If the simple argument against abortion is to fail, it will have to fail at the first premise: it is morally wrong to kill innocent human beings. The two main options are rejecting it, via Thomson’s rather controversial argument, or changing the premise to refer to persons, not human beings, and all that implies for infanticide. Are these compelling enough to confidently reject the simple argument against abortion? You decide.