A Problem For The "Future Like Ours" Argument Against Abortion.

Identity or continuity - take your pick.

Don Marquis’ “Future Like Ours” argument is widely considered by philosophers to be one of, if not the best arguments against the moral permissibility of abortion. It attempts to derive the immorality of abortion from the modest premises that the fetus has a future like ours, and that it’s wrong to deprive a thing of its future. Here, I offer a dilemma for the argument. Marquis can either say that the fetus must be numerically identical with the future subject of experience in order to be deprived of its future, or it must be related to the future subject of experience by a relation of physical continuity. Both options pose serious problems for his argument.

1. The Argument

If you want a detailed look at the argument, I suggest you read Marquis’ full essay. For now, I will describe the nuts and bolts of the argument.

Why is it wrong to kill adult human beings? There are many explanations on offer (some of which Marquis discusses in his essay). The best one, according to Marquis, is that killing an adult human being deprives them of their valuable future. When an adult human being dies, they lose out on valuable experiences they would have otherwise enjoyed and all of the things that they would have come to value. They’ll never get to feel the warmth of the sun on their face again, or spend time with their family, or take up new projects. To lose all of this is to suffer a great harm indeed. To inflict such a harm is seriously wrong.

Of course, killing a person is not always wrong. Killing in self-defense or killing to protect an innocent third party is sometimes justified. In these cases in which killing is not wrong, a strong countervailing moral reason is present. Depriving an adult human being of their valuable future is therefore prima facie wrong, in that it’s wrong unless some special countervailing reason is present. If killing adult human beings is prima facie wrong because it deprives them of their valuable futures, then any killing of a being which deprives it of its valuable future is also prima facie wrong. If we killed a rational space-alien, for instance, that killing would be prima facie wrong for the same reason it’s prima facie wrong to kill an adult human being. If fetuses have a future like ours - a valuable future - then killing them would be prima facie wrong too.

Do fetuses have a future like ours (“FLO”, hereafter)? To Marquis, it seems that they do. A fetus gradually grows inside its mother’s womb and eventually turns into an infant, and then a child, and then an adult human being. It goes on to have the sorts of experiences that we have now; it becomes one of us. As Marquis puts it:

“The future of a standard fetus includes a set of experiences, projects, activities, and such which are identical with the futures of adult human beings and are identical with the futures of young children” (Marquis 1989. p.4).

This is a gradual and unbroken process of development; if fetuses develop in the normal way, they go on to have valuable experiences. Fetuses have a FLO. Killing them deprives them of their FLO and is therefore prima facie wrong. Abortion kills a fetus, and so is prima facie wrong.

I have omitted some details here for the sake of brevity, but this is essentially Marquis’ argument. Let’s move on to the many objections one might make to this argument.

2. A Dilemma for Marquis

Two popular objections to Marquis in the literature are the ‘identity objection’ and the ‘contraception objection’. The identity objection says that the fetus cannot be deprived of its future because it is not numerically identical with the future subject of experience. The contraception objection says that the reasons Marquis gives to believe that abortion is wrong also apply to contraception, and that something must have gone wrong because contraception is clearly permissible.

Marquis and his defenders may have reasonable things to say in response to either of these objections when considered separately, but when considered jointly a problem seems to arise. What Marquis says to dispense with the contraception objection seems to strengthen the identity objection and vice-versa. Let’s start with the contraception objection.

2.1 Contraception/Abstinence Objection

Consider a sperm and an ovum separately. The sperm is swimming towards the ovum. Let’s suppose you have a button that will prevent the sperm from meeting with the ovum and fertilizing it. If you do this, it seems that you have deprived both the sperm and the ovum, considered separately, of a future like ours¹.

Why? Well, if you had not pressed the button, then the sperm would have fertilized the ovum, and a zygote would have been created. This zygote would eventually turn into a fetus, and then an infant, and then a child, and then an adult. This is a gradual and unbroken process of development. It seems that the same reasons we have to think fetuses have a FLO also apply to sperm and ovum. But if sperm and ovum have a FLO, then contraception would seem to be wrong, because it would deprive a sperm and ovum of their FLO. This may even entail that abstinence is wrong, as not having sex prevents sperm from fertilizing ovum.

These results are deeply counter-intuitive. Using contraception does not seem to be wrong at all, and certainly not as wrong as killing an adult human being in cold blood. If Marquis’ argument has these implications, then it’s likely that one of his premises is false. This objection suggests that either fetuses do not have a FLO to be deprived of, or depriving a thing of its FLO is only prima facie wrong in certain special circumstances.

At one point, Marquis responded to this objection by saying that if the sperm and ovum both lost a FLO when prevented from meeting, then “too many futures are lost”. Basically, the sperm and the ovum can’t both lose a future because then there would be two futures lost and not one (there is only one child after the whole thing is over with).

This is rather unpersuasive though. His objection relies upon the assumption that the number of individuals deprived by contraception must equal the number of futures lost. I think this is false. Two distinct individuals can both be deprived by the loss of one thing. For example, suppose me and my wife live in one home. Let’s say that a bomber destroys our home. Me and my wife will therefore be deprived by the loss of one thing.

Marquis has another response to this objection that is more persuasive, however. He says that in order for a being to lose a future it is necessary that…

“The future life that is lost would have been the actual life of the same individual who dies prematurely…”  (Marquis 2002, p.78).

What Marquis is saying is that if the sperm or the ovum is going to lose the future that we are according to the future child or adult, then the sperm or the ovum would need to be numerically identical with that future child or adult, and neither the sperm nor the ovum is numerically identical with that future child or adult. This is because numerical identity is taken to be a transitive relation (if you don’t know what numerical identity or transitivity is, read this footnote²).

If the sperm was identical with the zygote, and the ovum was identical with the zygote, then the sperm and ovum would be identical with each other. This is clearly false, so neither the sperm nor the ovum is identical with the zygote. Therefore, neither the sperm nor the ovum has a FLO. This is quite a clever response! Unfortunately, this creates a problem for Marquis known as the identity objection. There are several forms of this objection, but I shall present the one that is most persuasive to me.

2.2 The Identity Objection

Marquis has told us that if a thing is to be able to lose a future, it must be numerically identical with whoever the future subject of that future will be. This naturally raises the question: Are we numerically identical with the fetus that grew into our adult body? If we are not identical with our adult body, then we won’t be identical with the fetus either, because we are assuming with Marquis that identity is transitive. Unfortunately for Marquis, there seem to be extremely convincing reasons to believe that we are not identical with our adult body, on the assumption that identity is transitive.

Imagine a naturally two headed alien species. This species, when developing normally, grows two heads which each have their own distinct personalities and desires. These heads can talk to each other, and often disagree. If we met these two heads, we would probably give them different names and refer to them as distinct persons.

Here’s a question: are there two persons here, or just one? It seems that there are two people, but one organism. But this means that the two people cannot be identical with the organism, because, once again, identity is transitive. Let’s say person A is the right head and person B is the left head. Let’s call the body C. If A is identical with C, and B is identical with C, then A would be identical with B, and there would only be one person. This is false however; there are actually two persons there.

So, persons are not identical with their bodies (though they may be identical with a proper part of their body, such as the brain, or the functioning brain). This means that we are not identical with a fetus, which in turn means that fetuses don’t have FLO’s. In order for fetuses to have FLO’s, they need to be identical with the future subject of experience, and that would be us.

2.3 Trading Identity for Continuity

There is a response to the identity objection available to Marquis. He can trade in the identity requirement, which is too demanding, for something more relaxed. I can think of two things that fit the bill: physical continuity and psychological continuity. Psychological continuity is a no-go because early fetuses probably don’t have psychologies or minds. Physical continuity is what we’re left with.

A physical continuity relation between an adult human being and the fetus that preceded them, there certainly is. Unfortunately, if Marquis says that there need only be a relation of physical continuity between the fetus and the person in order for the fetus to possess a FLO, then the contraception objection is strengthened considerably. As we discussed earlier, there is a relation of physical continuity between the ovum and the zygote, and the sperm and the zygote. The contraception objection now seems much more troubling, and the dilemma should now have become apparent.

2.4 The Dilemma

It seems to me that Marquis is caught on the horns of a dilemma. He has two options, both of which spell trouble:

1. A relation of identity is necessary to give the fetus FLO, in which case the identity objection succeeds (see 2.2)

2. Some relation weaker than identity is necessary to give the fetus a FLO, in which case the contraception objection succeeds because the only plausible relation available is physical continuity (see 2.3)

There are ways out of this dilemma, but I expect they will be unpopular, and in any case, they each present difficulties that are at least as troubling as the dilemma itself.

2.5 Escape Route One - Deny Transitivity

As we saw, the transitivity of the identity relation renders the view that we are identical with the fetus that preceded us rather implausible. One could of course deny the transitivity of identity, and there may be plausible reasons to do so. Aaron Simmons (2011) has pointed out that if physical continuity and psychological continuity are both intransitive - as they are widely considered to be - then it seems we need a special reason to think that identity is transitive. If we take other relations central to personal identity to be intransitive, then why should we have any confidence that human identity itself is transitive?

The lesson here is just that there are independent reasons to deny transitivity other than a desire to salvage Marquis’ argument. If we are persuaded by these reasons, then it seems the identity objection is dealt with; the two persons of the two headed alien can both be identical with the organism without being identical to each other if identity is intransitive.

Unfortunately, this strengthens the contraception objection. If identity is intransitive, then the sperm and the ovum can be identical with the zygote without being identical with each other. Of course, the sperm and the ovum may be non-identical with the zygote even if identity is intransitive, but whatever reason that is given for thinking that must also avoid entailing that we are non-identical with the fetus that preceded us; that may be hard to do considering that in both cases we observe a gradual, unbroken process of change and development.

2.6 Escape Route Two - Double Down on Animalism and Keep Transitivity

The view that we are identical to a human organism (our current body) is called animalism. One could respond to my dilemma by doubling down on animalism, taking issue with my two-headed alien objection.

For example - what if we split the two headed alien into two halves, and then administer medical care to the two halves, such that the two sides are able to stay alive? If that is possible, then it seems that my two headed alien is not one organism at all, but really two organisms that overlapped, or that were fused together. I don’t find this plausible because you can split a starfish into two living halves, but surely the starfish is one organism prior to being cut in two.

There are, of course, other objections one could make to my case, but for now I will set those aside. Let’s assume that there is something wrong with my argument against animalism. This would not be absurd or incredible. Let’s say that animalism is true. We are identical to our current adult human body, which is identical to the fetus that preceded us. The identity requirement for having a FLO is met. No issues here, right? Wrong. The identity requirement proposed by Marquis is problematic because it has an absurd implication.

Consider Fiona. Fiona is a ten week old fetus scheduled for an abortion on Tuesday morning. Suppose that if Fiona is not aborted on Tuesday morning, Fiona will divide like an amoeba on Tuesday afternoon. If Fiona divides on Tuesday afternoon, Fiona will cease to exist. In this case, Fiona is not numerically identical to any future subject of experience (the children that will result from the two new fetuses are the only candidates available).

Is it wrong to abort Fiona? If being deprived of a FLO requires identity to the person who experiences that future, then the answer is no. This alone is quite a worrying implication. Things get weirder when you consider that if Fiona was not going to divide, then aborting Fiona would be wrong. Tim Burkhardt describes the absurdity of this result quite well: Marquis claim implies…

“that although being biologically continuous with a single experiencer of a valuable future is sufficient for Fiona to be deprived by abortion, being continuous with two such experiencers means that abortion deprives her of nothing. The claim that being deprived of a future requires identity to its experiencer must therefore be false.” (Burkhardt, 2020).

And if this claim is indeed false, then Marquis has lost his ticket away from the contraception objection once again. If identity to the future experiencer is not required to be deprived of a future, then the sperm and ovum need not be identical with the zygote they create to share its future.

There is perhaps another problem with endorsing animalism as a way to escape the dilemma. Even if it is the case that we are identical with the fetus, it may not be the case that the fetus can be deprived of its future in the morally laden sense that you or I can be deprived of our futures by being killed. Perhaps mere identity is not sufficient.

In section (2.7), I consider two thought experiments - Pinocchio Log and Robot Chassis - in which it seems to me that a thing is numerically identical with a future subject of experience and yet not deprived by being taken out of existence. In section (2.7) I use the thought experiments to object to the biological account of death, but I also think they show that identity is not sufficient for deprivation, even if it’s necessary. I leave it to the reader to consult their intuitions when those thought experiments are detailed.

2.7 Escape Route Three - Biological Account of Death

In that last section, we came to the conclusion that one can be deprived of a future even if they are not numerically identical to the future experiencer. One might wonder if Marquis could use this to his advantage, however. If the identity requirement is done away with, then the identity objection disappears, and Marquis just has to deal with the contraception objection. Now Marquis needs to find some symmetry breaker between the fetus and the sperm and ovum considered separately.

Thus far, I have argued that no symmetry breaker exists, as there is physical continuity to the future experiencer in both cases. One could argue, however, that not all is equal here. Julian I Kanu has recently proposed a solution to the contraception reductio along these lines in his paper “Strengthening Harm Theoretic Pro-Life Views”. In that paper, he proposes a deprivation account of the wrongness of killing called the Biological Account of Death (BAD).

“BAD claims that you³ are deprived of a future of value to the extent you are biologically connected to your future, and the number and quality of goods you have in the future. Biological connectedness at time t1 to time t2 is a measure of how related, and continuous, the structure and function of the organism is at t1 and t2. The more related the character of the organism at the two times, the stronger the biological connection.”

Kanu claims that his account:

A. Explains why contraception is not wrong, but abortion typically is;

B. Is superior to other deprivationist accounts such as Jeff McMahan’s time relative interest account (TRIA), as it accommodates our intuitions in more cases than TRIA and similar accounts; and,

C. Retains all the benefits of other deprivationist accounts such as TRIA.

I have several problems with BAD. The first is that I don’t think BAD accomplishes C. BAD claims that you are deprived of a future of value to the extent you are biologically connected to your future, and not just physically connected. If beings are only deprived of their futures to the extent that they are biologically connected to them, then sentient, rational, non-organic physical persons and sentient, rational non-organic non-physical persons cannot be deprived of their futures on BAD. I find this to be absurd. I think a sentient robot could be deprived of their future of value. I also think that a non-physical soul or mind could be deprived of its future. Jeff McMahan’s TRIA can accommodate this fact, and therefore has an advantage over BAD.

Additionally, it seems that I could become a non-organism. For example, I could become a cyborg. If we replace enough of my organic parts with non-organic ones, it seems that I will eventually cease to be an organism (at the very least, it seems that my biological connectedness to my future self is decreased). Let’s stipulate that this is to happen to me very quickly after I am born. In this case, I will have very little (if any) biological connectedness at all to my future self. Yet, If I were to be killed before this happens, I would be deprived of my future to the exact same extent I would have been in a world where I was never going to become a cyborg. If BAD is true, this can’t be the case. My becoming a cyborg would at least decrease my biological connectedness to my future self. If deprivation is a function of biological connectedness and future goods, then the less biologically connected I am to my future, the less serious is the deprivation of my future.

Defenders of BAD will reply by saying that BAD merely offers sufficient conditions, and not necessary ones. Defenders of BAD are therefore free to postulate additional reasons why death is bad or wrong in order to explain cases where BAD doesn’t apply. This is entirely consistent, but the plausibility of BAD goes down the more reasons we have to postulate. Ceteris Paribus, we should prefer simpler explanations of why death is bad or wrong. The more reasons we postulate, the less parsimonious our cumulative theory.

Kanu claims that BAD is superior to TRIA in that it explains why it is wrong to kill a newborn infant who has never had any mental states yet but will have mental states tomorrow. Kanu thinks it would clearly be wrong to kill such a being, and that any account that accommodates this intuition has an advantage over accounts that do not. I am not so sure. In this particular case, the picturing of an infant in our brains may be leading our intuitions astray. I say this because of the following thought experiments:

Pinocchio Log - Geppetto takes a wooden log and soaks it in a special resin. This special resin imbues the log with magic, making it so that in 9 months, the log will be sentient and rational, just like an ordinary adult human being. Geppetto waits and waits, and eventually it is 1 day before the log will become sentient and rational. It just so happens that on that particular night, Geppetto is quite cold. He has no firewood besides the log he soaked in the special resin. He decides to burn the log as firewood. The log never becomes conscious or sentient.

Robot Chassis - You build the frame of a robot. On the back of its head, there is a port for a silicon chip. You build a silicon chip that, once plugged in, will become conscious in 9 months. You plug the chip in and let the program do its thing for a few months. Eventually, you change your mind about creating a conscious robot and pull the chip out and break it in half.

Did Gepetto do something wrong? It does not seem like it, but Pinocchio log is analogous to Kanu’s comatose infant case in all the relevant ways. Both the log and the infant have never had mental states before, and will tomorrow. Sure, the log is not an organism, but why would that matter? It’s true that most people would say that killing the comatose infant is wrong, but most people would not say that destroying Pinocchio log is wrong. We seem to have a conflict of intuitions.

One straightforward way to explain the conflict of intuitions is that when people picture a comatose baby, they imagine the sort of being that has usually already had mental states and that we have strong innate feelings of care and affection for. As such, their innate instinct to protect the baby and the fact that the baby looks like other beings that do have mental states biases their intuition. In fact, some people seem to be uncomfortable with the “abuse” (shredding or burning) of realistic baby dolls even though they know there is no baby there. It seems that people have trouble not projecting their feelings about actually existing babies onto things that resemble babies.

If the fact that the being will become sentient tomorrow is really what is generating the intuition in the comatose baby case, then our intuitions should tell us that destroying pinnochio log is wrong. This is not what our intuitions say about pinnochio log, however (I trust this intuition is widely shared). This makes it doubtful that BAD really enjoys any advantage over other deprivation accounts. BAD does not seem to accomplish B.

It’s also likely that BAD fails to accomplish A. In order for BAD to accomplish A, it must be the case that there is a much stronger degree of biological connectedness between a fetus and the resulting child, than between the sperm and the ovum, and the resulting zygote. This is because contraception is not just less wrong than depriving a person of their future of value, it’s totally morally innocuous. It cannot just be that the degree of biologically connectedness is slightly weaker or even moderately weaker, it must be much weaker. But is the degree of biological connectedness really much weaker? Kanu thinks so:

“One prime marker of biological character is chromosomes. And, the sperm, and the egg are both haploid cells before conception, and they make a diploid cell at conception. Under this light, we can argue that there is a similarity in chromosomes present in zygote, which exists in the future person, who obtains the future of value, which is not present in sperm, the egg, or its composite, and therefore, the zygote is more biologically connected and more harmed by death.”

This is true, of course. Zygotes have chromosomes that the sperm and the egg taken separately don’t have prior to conception. There are also many similarities between sperm and ovum taken separately and zygotes, which are not found between zygotes and children. For example, both zygotes and children are larger than sperm and ovum. Both sperm, ovum, and zygotes lack limbic systems, blood vessels, tendons, muscles, and brains. All things considered, it looks as if zygotes are far more biologically similar to sperm and ovum than children. Kanu responds to this sort of worry like this:

“there are big biological differences throughout development. Why does the biological change at conception become the point where it is no longer permissible to kill the being? As with any gradualist position on deprivation, it is oftentimes hard to give a cut-off. The best we can look for is a point that is not completely arbitrary. Because DNA is oftentimes thought of as a characteristic of biological identity, it does not seem unreasonable to use the number of chromosomes as the deciding factor.”

While Kanu thinks the selection of DNA as the deciding factor is not completely arbitrary, it does appear that way to me. Why does DNA matter if, on the whole, the process of biological development from sperm and ovum to fertilized is gradual, un-broken, and continuous, and it’s also the case that sperm and ovum are far more like zygotes than zygotes are like human children? This seems to be an arbitrary selection, if there ever was one. Even if we grant that the difference in DNA constitutes some difference in biological connectedness, it does not seem to be so great as to constitute the difference between a morally innocuous action and one that is gravely wrong.

On BAD, you are deprived of your future “to the extent you are biologically connected to your future”. The more biologically connected to your future, the greater the loss. On BAD, a deprivation can be more or less bad depending on how connected you are to your future. Consider how connected sperm and ovum are to the zygote they create - there is a strikingly gradual process of development. Now consider how connected a fetus is to the child it will grow into. Can it really be the case that in one of these cases, no deprivation worth caring about occurs, but that in the other, a serious wrong is committed, simply because there is a change in the number of chromosomes? I simply don’t see why this would be the case.

More troubling perhaps, is the threat of Burkhardt’s thought experiment (Fiona from 2.6). We can run this thought experiment against BAD as well - Fiona does not have the same number of chromosomes as either of the two embryos Fiona divides to create. So, if Fiona is biologically continuous with one experiencer she is deprived by death, and if she is biologically continuous with two, death deprives her of nothing. This is a very odd result. Perhaps this result illustrates the arbitrary nature of the decision to make the number of chromosomes the deciding factor.

3 Concluding Thoughts

Marquis is caught on the horns of a dilemma and his only plausible escape routes lead to problems at least as troubling as the dilemma itself. There may be a way out of it, but if it exists then it escapes me at the present moment. Despite my problems with the argument, I believe it represents a monumental contribution to the abortion ethics literature, and is easily the best argument against the moral permissibility of abortion.

No other argument against abortion has captivated me like this one - no other argument has had me staying up, genuinely considering the possibility that abortion is gravely wrong. It’s in that spirit of a genuine interest in the true and the good that I publish these objections, and hope to prompt further reflection and discussion. The abortion debate is often ugly, but I hope that in this space we can conceive ourselves not as partisan warriors, but as rational individuals with a passion for cultivating understanding about this complex ethical issue. Let’s help each other get to the bottom of this - I am open to any objections.

1. There is another version of the contraception objection that says the sperm and the ovum are deprived of a future when considered as a union. That is, the sperm and the ovum constitute one single thing that is deprived of a future. Why think that the sperm and the ovum could constitute a further object? Well, there are these things called composite objects. A composite object is simply an object that has parts. Sometimes, these parts have space in between each other, and yet they still compose a further object. So even if two things are separated by space and can be distinguished from each other, they may still compose a further object.

2. Numerical identity is the relation that every object has to itself. The term refers to the fact that an object is the same thing as itself, and not the same thing as something else. I am numerically identical with myself and not you. This is distinct from what we call qualitative identity. Two things are qualitatively identical when they share all properties besides the property of numerical identity. For example, identical twins are qualitatively identical (or at least very similar). They share many properties. Nonetheless, identical twins are not numerically identical; there are two twins there, not one! Now what is transitivity? Consider this: A is taller than B, and B is taller than C. If that’s true, then A must be taller than C, right? This is transitivity. The relation of “taller-than” passes through one element to another (in this case, through B and to C). Basically, if A and B share some relation, and B and C share some relation, then A and C share that same relation. There are lots of things like this. Better-than is transitive for instance. Why would numerical identity be transitive? As we said, numerical identity is the relation that every object has to itself. Let’s say that A is numerically identical to X. They are the same thing. Let’s also say that B is numerically identical to X. They are the same thing. If A and B are both the same thing as X, then how could A and B be two distinct things? It seems they cannot. This is why numerical identity is taken to be transitive. This has interesting implications for the nature of personal identity.

3. The use of “you” in this sentence is itself problematic. By saying that “you” are deprived of your future when “you” are killed as a fetus, Kanu seems to be smuggling in the thesis that you are numerically identical with the fetus. Kanu can restate his thesis to say that the fetus is deprived, and not “you”, if he wishes to avoid this problem.