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People-Seeds An Analogy In The Abortion Argument Essay

Abortion and the People Seeds Thought Experiment


(Entry on the violinist thought experiment)

The most widely discussed argument against abortion focuses on the right to life. It starts from something like the following premise:

  • (1) If an entity X has a right to life, it is impermissible to terminate X’s existence.

This premise seems plausible but needs to be modified. It does not deal with the clash of rights. There are certain cases in which rights conflict and need to be balanced and traded off against each other. The most obvious case in the one in which one person’s right to life conflicts with another person’s right to life. In those cases (typically referred to as ‘self defence’ cases) it may be permissible for one individual to terminate another individual’s existence. Abortion may occasionally be permitted on these grounds. For example, the foetus may pose a genuine threat to the life of the mother and so her right to life might be taken to trump the foetus’s right to life (assuming, for the sake of argument, that it has such a right).

The more difficult case is where the foetus poses no threat to the life of the mother. The question then becomes whether the mother’s right to control what happens to her body trumps the foetus’ right to life. Judith Jarvis Thomson’s famous article ‘A Defense of Abortion’ tries to argue the affirmative answer to this question. It does so through a series of fanciful and ingenious thought experiments. The most widely-discussed of those thought experiments is the violinist thought experiment, which supposedly shows that the right to control one’s body trumps the right to life in cases of pregnancy resulting from rape. I presented a lengthy analysis of that thought experiment in a recent post.

Less widely-discussed is Thomson’s ‘People Seeds’ thought experiment and it’s that thought experiment that I wish to discuss over the remainder of this post. I do so with some help from John Martin Fischer’s article ‘Abortion and Ownership’, as well as William Simulket’s article ‘Abortion, Property and Liberty’.

1. People Seeds and Contraceptive Failure
Here is Thomson’s original presentation of the ‘People Seeds’- thought experiment.

[S]uppose it were like this: people-seeds drift about in the air like pollen, and if you open your windows, one may drift in and take root in your carpets or upholstery. You don’t want children, so you fix up your windows with fine mesh screens, the very best you can buy. As can happen, however, and on very, very rare occasions does happen, one of the screens is defective; and a seed drifts in and takes root. 
(Thomson 1971, 59)

Now ask yourself two questions about this thought experiment: (1) Do you have a right to remove the seed if it takes root? and (2) What is this scenario like?

In answer to the first question, Thomson suggests that the answer is ‘yes’. You have no duty to allow the people-seed to gestate on the floor of your house just because one happened to get through your meshed curtains. Your voluntary opening of the windows does not give an insurmountable right to the people-seeds. In answer to the second question, it is supposed to be like the case of pregnancy resulting from contraceptive failure. Arguing by analogy, Thomson’s claim is that the moral principle governing the ‘People-Seed’-case carries over to the case of pregnancy resulting from contraceptive failure. So just as the right to control what happens to one’s property trumps the people-seed’s right to life in the former, so too does the right to control what happen’s to one’s body trump the foetus’ right to life (assuming it has one) in the latter. I have tried to illustrate this reasoning in the diagram below.

This argument is significant, if it is right. Thomson’s violinist thought experiment could only establish the permissibility of abortion in cases of involuntary pregnancy (i.e. pregnancy resulting from rape). The ‘People-seeds’ thought experiment goes further and purports to establish the permissibility of abortion in cases of voluntary sexual intercourse involving contraceptive failure. Is the argument right?

2. Counter-Analogies to People-Seeds
I’m going to look at John Martin Fischer’s analysis of the ‘People-Seeds’-thought experiment. I’ll start with an important preliminary point. Whenever we develop and evaluate a thought experiment, we have to be careful to ensure that our intuitions about what is happening in the thought experiment are not being contaminated or affected by irrelevant variables.

Thomson’s stated goal in her article is to consider the permissibility of abortion if we take for granted that the foetus has a right to life. Obviously, this is a controversial assumption. Many people argue that the foetus does not have a right to life because the foetus is not a person (or other entity capable of having a right to life). Thomson is trying to set that controversy to the side. She is willing to accept that the foetus really does have a right to life. Consequently, it is important for her project that she uses thought experiments involving entities that clearly do have a right to life. The violinist thought experiment clearly succeeds in this regard. It involves a fully competent adult human being — an entity that uncontroversially has a right to life. It’s less clear whether the people-seeds thought experiment shares this quality. It could be that when people are imagining the scenario they don’t think of the people-seeds as entities possessing a right to life (perhaps they think of them as the equivalent to sperm cells getting lodged in your carpet - they will take a bit of time to become people). Consequently, their conclusion that there is nothing wrong with removing the people-seeds from the carpet might not be driven by intuitions regarding the trade off between the right to life and the right to control one’s property but rather by intuitions about the right to control one’s property simpliciter.

Fischer thinks there is some evidence for this interpretation of the thought experiment. If you run an alternative, but quite similar, thought experiment involving an entity that clearly does possess a right to life, the conclusion Thomson wishes to draw is much less compelling. Here’s one such thought experiment coming from the philosopher Kelly Sorensen:

Imagine you live in a high-rise apartment. The room is stuffy, and so you open a window to air it out. You don’t want anyone coming in…so you fix up your windows with metal bars, the very best you can buy. As can happen, though, the bars and/or their installation are defective, and the Spiderman actor [who is filming in the local area]…falls in, breaks his back in a special way, and cannot be moved, without ending his life, for nine months. Are you morally required to let him stay? 
(Fischer 2013, 291)

The suggestion from Fischer is that you might be under such an obligation. But if this is right, then it possibly provides a better analogy with the case of pregnancy resulting from contraceptive failure and a reason to think that the right to control one’s body does not trump the right to life.

Another point that Fischer makes is that your role in causing the entity in question to become dependent on you (your body or your property) might make a relevant difference to our moral beliefs. Thus, the fact that Thomson’s thought experiment asks us to suppose that the people-seeds are just out there already, floating around on the breeze, waiting to take up residency on somebody’s carpet, might be affecting our judgment. In this world, you are constantly in a defensive posture, trying to block the invasion of the people-seeds. If we changed the scenario so that you actually play some positive causal role in drawing them into your house/apartment we might reach a different conclusion. So here’s a slight variation on Thomson’s thought experiment:

Suppose that you can get some fresh air by simply opening the window (with the fine mesh screen), but still, you would get so much more if you were to use your fan, suitably placed and positioned so that it is sucking air from outside into the room. The only problem is that this sucks people-seeds into the room along with the fresh air. 
(Fischer 2013, 292)

The suggestion is that this is much closer to the case of pregnancy resulting from contraceptive failure. After all, voluntarily engaging in sexual intercourse (even with contraception) involves playing a positive causal role in drawing into your body the sperm cells that make pregnancy possible.

In sum, then, we have two counter-analogies to Thomson’s ‘People-Seeds’-thought experiment. The suggestion is that both of these thought experiments are closer to pregnancy resulting from contraceptive failure and so the moral principle that applies in both should carry over to that case. The right to control one’s body does not trump the right to life.

3. Analysis of the Counter-Analogies
There are two problems with these counter-analogies. The first is simply that they do not compare like with like. This is a problem with all thought experiments that are intended to provide analogies with pregnancy, including Thomson’s. Pregnancy is, arguably, a sui generis phenomenon: there are no good analogies with it, period. Consequently, it is very difficult to build a moral argument for (or against) abortion by simply constructing elaborate and highly artificial thought experiments that pump our intuitions about the right to life in various ways. Furthermore, even if you hold out some hope for the analogical strategy, there is something pretty obviously disanalogous about the two scenarios: all the thought experiments involve interferences with the right to property not with the right to control over one’s body. Perhaps one has a property right over one’s body. Even still, the degree of invasiveness and dependency involved in pregnancy is quite unlike someone taking up residency on your carpet.

Another problem with the thought experiments is the normative principles underlying them. The whole discussion about pregnancy and contraceptive failure is motivated by the belief that consent matters when it comes to determining the rights claims that others have over us. Pregnancy from rape is distinctive because it involves a lack of consent. One person impregnates another against their will. It seems intuitively plausible (irrespective of the ranking one has of different rights) to assume that duties cannot be easily imposed on someone without their consent. Pregnancy from contraceptive failure is different because (a) everyone knows that pregnancy is a possible (if not probable) result of sexual intercourse even when it takes place with contraceptive protection and (b) by consenting to the sexual intercourse it seems like you must be willing to run the risk of this possible result. Consequently, it doesn’t seem quite so far-fetched to suppose that you might be voluntarily incurring some duties by engaging in the activity.

This line of reasoning, as William Simulket sees it, is motivated by the following consent principle:

Consent principle: When an agent A freely engages in action X, A consents to all possible foreseeable consequences of X.

At first glance, this seems like a plausible principle and if it is correct it would seem to imply that A incurs certain obligations or duties with respect to X. But according to Simulket (and Thomson) this consent principle cannot possibly be correct because it entails absurd consequences. It entails that women are ‘on the hook’ (so to speak) for all the possible pregnancies that might befall them (irrespective of whether they consented to the sexual activity that led to the pregnancy) because rape is a possible foreseeable consequence of being alive and walking about in the world, and hence women who refuse to get hysterectomies must have consented to the possibility of pregnancy resulting from rape. Thomson put it like this in her original article:

…by the same token anyone can avoid a pregnancy due to rape by having a hysterectomy, or anyway by never leaving home without a (reliable!) army. 
(Thomson 1971, 59)

And Simulket explained the idea in his article as follows:

The circumstances that we face are, largely, outside of our control. But whether we have invasive surgery to remove our reproductive organs is, largely, within our control. It is uncontroversially true that any of us might be raped at some point in the future. Therefore, according to this argument, women who realize that rape is possible but who do not have a hysterectomy have consented to becoming pregnant from sexual assault. 
(Simulket 2015, 376)

Simulket also suggests, along similar lines, that the consent principle, if true, would entail that we all consent to all the possible foreseeable misfortunes that befall us because we could have avoided them by committing suicide. It is, of course, absurd to assume that if we wish to avoid responsibility for what happens to us we must get hysterectomies or commit suicide, hence the consent principle must be wrong.

I’m not sure what to make of this. I agree with Simulket and Thomson that the strong version of the consent principle — the one that holds that we are on the hook for all possible foreseeable consequences of what we do — must be wrong. But obviously some version of the consent principle must be correct (perhaps one that focuses on results that are reasonably foreseeable or probable). After all it is essential of our systems of contract law and legal responsibility that we incur duties through our voluntary activity.

If this is correct, then maybe Thomson’s thought experiments succeed in showing that the right to control one’s body trumps the right to life of the foetus (assuming it has one) in cases of pregnancy resulting from contraceptive failure, but it does nothing to show whether the same result holds in cases of unprotected consensual sexual intercourse. Those cases might be covered by a suitably modified version of the consent principle. If we want to argue for a pro-choice stance in relation to those cases, we may need to focus once more on the question of who or what bears a right to life.

Section 4. Is abortion unjust killing?

Thomson begins this section by considering that “in the most ordinary sort of case, to deprive someone of what he has a right to is to treat him unjustly.”  She illustrates this with the following analogy: “Suppose a boy and his small brother are jointly given a box of chocolates for Christmas. If the older boy takes the box and refuses to give his brother any of the chocolates, he is unjust to him, for the brother has been given a right to half of them. But suppose that, having learned that otherwise it means nine years in bed with that violinist, you unplug yourself from him. You surely are not being unjust to him, for you gave him no right to use your kidneys, and no one else can have given him any such right.” I really think that Thomson is abusing the analogy by extending it to a long period of time. What we must keep in mind is that pregnancy is intrinsically ordered toward procreation. It was never meant to last a long period of time because one of the most basic of human drives is procreation, to continue the species. So it seems that whether or not you’d have to remain plugged into the violinist an extended period of time is really irrelevant to whether or not it is just to forbid a woman from having her offspring killed. Additionally, we aren’t given any information as to the violinist. Would he want to remain in such a state plugged in for nine years? What if the violinist is seventy years old and not likely to survive all that time anyway? It seems that there are even factors affecting the violinist that should be considered if you are going to decide whether or not to remain plugged in.

Thomson here amends her earlier assessment of a right to life, that it’s not just the right not to be killed, but the right not to be killed unjustly. She’s getting closer, at least. But now she claims that it runs the risk of circularity in its definition (which it does not). It seems that from start to finish in her essay, Thomson is not being as fair to pro-life advocates as she claims she is being. It is wrong to kill any human being unjustly. All we are saying is that since the unborn are human beings, if a strong moral justification is needed to kill a human being outside the womb, the same strong moral justification is needed to kill someone inside the womb. There is nothing circular about this argument. Granted, Thomson is arguing for a “right” to abortion based on a similar justification for letting someone die outside the womb; my complaint here is that she’s not really being as fair to pro-life people as she thinks she is. She turns to a consideration regarding the proposition that if the unborn are persons, is abortion, then, an unjust killing?

Thomson now suggests that no woman actually gives an unborn child a right to use her body, stating, “It is not as if there are unborn persons drifting about the world, to whom a woman who wants a child says I invite you in.” This is how she tries to avoid the responsibility objection in cases other than rape. It doesn’t work, though, because by engaging in sexual intercourse, an act intrinsically ordered toward procreation, she tacitly gives her consent to the preborn child’s presence in the womb. Thomson anticipates this objection, stating that if this were the case, then abortion would be “more like the boys taking away the chocolates, and less like your unplugging yourself from the violinist -- doing so would be depriving it of what it does have a right to, and thus would be doing it an injustice.”

Needless to say, her responses to this objection are incredibly weak. First, she asks that if she is responsible for bringing it into existence, then why does she have the right to kill it, even to save her own life? This seems powerful at first, but we must keep in mind that simply bringing an entity into existence does not mean that you don’t have the right to protect yourself from it. Children have been known to kill their parents. If a child turns on his parents, even as an “innocent aggressor,” they have a right to protect themselves.

Her second point is simply that it’s new. She claims that pro-life people have been so concerned about the independence of the fetus that they tend to overlook the possibility that the parents’ responsibility may give the fetus a claim to her body which other independent people may not have, such as an ailing violinist who is a stranger to her. Her response to this is simply that it would leave out children conceived in rape, that aborting them is not depriving them of anything they have a right to. But that’s not an objection, it’s simply the logical conclusion of the responsibility objection. I believe that it should be illegal to abort children conceived in rape (see my linked article for why). Those who do not share my convictions believe that abortions, while still immoral, should not be legally prohibited in the case of rape exactly for this reason -- and it would justify only about 1-2% of abortions. So Thomson’s objection here is really not an objection at all.

Thomson presents two further thought experiments to explain her point, to try and show that the responsibility objection does not go as far as pro-life people believe it does.

The burglar

“If the room is stuffy, and I therefore open a window to air it, and a burglar climbs in, it would be absurd to say, ‘Ah, now he can stay, she’s given him a right to the use of her house -- for she is partially responsible for his presence there, having voluntarily done what enabled him to get in, in full knowledge that there are such things as burglars, and that burglars burgle.’ It would be still more absurd to say this if I had had bars installed outside my windows, precisely to prevent burglars from getting in, and a burglar got in only because of a defect in the bars. It remains equally absurd if we imagine it is not a burglar who climbs in, but an innocent person who blunders or falls in.”

Thomson equates pregnancy with burglary. In The Ethics of Abortion (Routledge, New York, NY, 2011, p. 162), Christopher Kaczor responds, “...the woman’s action of leaving the door unlocked does not cause the burglar to be in the house -- opening the door only removes an obstacle. On the other hand, the man and the woman cause the baby to be where it is, even if they tried to prevent it (just as a drunk driver causes deaths though she may have tried to prevent it, say by drinking coffee to stay alert).”

In his book, The Case for Life (Crossway Books, Wheaton, IL, 2009, p. 192), Scott Klusendorf, when addressing a similar argument made by Eileen McDonagh (that the fetus is like a mugger), responds in this way: “...the analogy is not at all parallel to a pregnant woman and her child. The fetus, even if unwanted, cannot be responsible for its own existence...As Frederica Mathewes-Green points out, there can be no ‘mugger’ until two ‘joggers’ combine genetic material to create him. On what grounds, then, can any parent who willingly engaged in a sexual act that leads naturally to the creation of a dependent child deny responsibility for him?”

Kaczor adds two more disanalogies between pregnancy and the burglar scenario (pp. 164-165). First, the burglar knowingly and willingly breaks the law by entering your house uninvited and taking your items, so he forfeits some of the rights enjoyed by an innocent person. Even if someone wanders into your house (say a small child or an elderly woman with dementia), you do not have the right to kill that person if that’s the only way you can make them leave.

Finally, the act of leaving doors and windows open, unbarred, etc., does not in itself lead to burglars entering homes in the same way that the act of sexual intercourse leads to pregnancy. He says, “suppose that leaving doors unlocked often led to young children or elderly neighbors wandering innocent into your house. Suppose we spoke of leaving doors ajar as the “neighbor-inviting act,” just as we speak of sexual intercourse as the generative act or reproductive act. Suppose further that you caused the child or elderly neighbor to be in your house, say by grabbing a child or an octogenarian who looked very much like your own niece or grandma off the street and dragging the person into your house. Even if you couldn’t find another way of getting herself out of your house as quickly as you’d like, you would hardly be justified in killing her, because she is in your house only because of your own actions.”

In short, the burglar analogy does not combat the responsibility objection; it only reinforces it.


For her next analogy, Thomson writes the following: “Again, suppose it were like this: people-seeds drift about in the air like pollen, and if you open your windows, one may drift in and take root in your carpets and upholstery. You don’t want children, so you fix up your windows with fine mesh screens, the very best you can buy. As can happen, however, and on very, very rare occasions does happen, one of the screens is defective, and a seed drifts in and takes root. Does the person-plant who now develops have a right to the use of your house? Surely not -- despite the fact that you voluntarily opened your windows, you knowingly kept carpets and upholstered furniture, and you knew that screens were sometimes defective. Someone may argue that you are responsible for its rooting, that it does have a right to your house, because after all you could have lived out your life with bare floors and furniture, or with sealed windows and doors. But this won’t do -- for by the same token anyone can avoid a pregnancy due to rape by having a hysterectomy, or anyway by never leaving home without a (reliable!) army.”

Now Thomson just gets silly. Aside from the fact that the objections to the burglar scenario work here, too (you are not responsible for the people-seeds drifting in, you were merely removing an obstacle to their implanting in your house, and that opening doors and windows is not an act intrinsically ordered toward bringing people-seeds into your house), John T. Wilcox, in his essay Nature as Demonic in Thomson’s Defense of Abortion (found in The Ethics of Abortion: Pro-Life vs. Pro-Choice, ed. Robert M. Baird and Stuart E. Rosenbaum, Prometheus Books, Amherst, NY, 2001, pp. 264-265), highlights the difficulty of using science fiction scenarios to test our actual world intuitions: “What would such a world really be like? If people-seeds are like pollen, would putting up screens help at all? Would not you, the house resident, be giving off seeds yourself, and so trapping your own pollen-seeds in your house? Or rather: since pollen is not the right metaphor, after all: would you not have to keep people who gave off pollen out of your house, because their pollen might fertilize your flowers, and then you would give off seeds (like dandelion seeds, say, not like pollen) which might be trapped in your house? And you would like your fertilized seed to be cared for by someone else rather than yourself? Or what? We really are not told enough to know what such a world would be like, and hence what kinds of obligations for their seed-children we might think parents would have...This sort of problem is found in almost all science fiction arguments. Our ethical intuitions are shaped by this world and would be clumsy in a real other world; but when we are not really transported to another world, but only asked to imagine a little bit of another one, our intuitions fail us entirely.”

Pro-life philosopher Frank Beckwith talks about this “possible world” (I really don’t think there is a possible world in which humans reproduce by “people-seeds,” but he’s probably just being generous to the scenario). He continues the point I mentioned in the first part of this series, that Thomson really is not granting the pro-life position regarding human personhood. He writes: “ the seed-sowing world, an essential property of a sowed seed is the generation of a mature version of itself as a plant-person. Consequently, Thomson’s seed-drifting world seem plausible to her because she rejects a philosophy of the human person that is embraced by virtually all pro-lifers: our sexual powers are ordered toward the generation of children whose progenitors are required to care for them. What Thomson is granting, then, is a view of personhood consistent with the pro-life position only insofar as it is aligned with a minimalist understanding of autonomy and choice. That view isolates the individual from other persons -- generationally, contemporaneously, and institutionally -- except as those relationships arise from the individual’s explicit choice. But that is not the pro-life view of personhood.”

So the burglar and people-seed analogies fail to justify the act of abortion. She continually mentions rape, but as I have written previously, even if abortion is justified in that case, that would only justify it in the case of rape. Justifying abortion in the case of rape would not justify abortion-on-demand, a fact that Thomson seems all too eager to ignore.

The preceding article also appeared on the Secular Pro-Life blog.