Chimeras, Monozygotic Twins, and the Beginning of Life

Philosophy Forums Religion and Spirituality
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This flowchart shows all the paths by which a fertilized egg becomes a living human. Of particular note are two paths: The path that produces monozygotic twins (subscript mz on the chart), and the path that produces a chimera (subscript ch on the chart). These paths are of note because they represent changes in the number of developing organisms well after fertilization. In the case of monozygotic twins, the developing organism divides and the cells become separated, but each separate cluster of cells continues dividing as its own organism. In the case of the chimera, the process is the opposite: two organisms developing from two fertilized eggs begin developing as one, retaining both sets of genetic information but forming one individual.

The importance of these in debates around the start of human life is this: individual life cannot possibly be said to begin as soon as the egg is fertilized, because in some circumstances, the number of lives increases or decreases, without death or additional fertilizations, up to a week and a half following fertilization. That is to say, the number of fertilized eggs does not determine the number of developing organisms.

This seems important to the abortion debate generally, but particularly in relation to treatments like the morning after pill. The process of division and combination of developing cell clusters ends with implantation, and the morning after pill simply prevents implantation. If life begins at implantation, then there can be no moral consequence to preventing implantation, because the life has not begun. It is comparable to any other form of birth control.

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I don’t know how accurate it is one way or another, but its a great pictorial.

As far as that debate, I’m not so sure it would help that much.
“So you are possibly murdering several lives instead of just one… sniff.”

You can’t really say that it isn’t life merely because it might become two lives.
“I didn’t kill out that species. It might have become many species!”

3

Well, you can’t say that life begins at the moment the egg is fertilized, because the number of lives isn’t determined then (i.e., at least some of the time, lives come into being some time after ferilization).

Nor can you say that each fertilized egg is at least one life, since chimeras form from two fertilized eggs. It therefor doesn’t seem like you can coherently hold that in ending the development of a fertilized egg before implantation you’ve commit an act morally equivalent to murder: a fertilized egg might end up being only half a life( less - my understanding of chimeras is that the same process can involve more than two eggs).

Whatever it does, it certainly poses a problem for any hard and fast moral line, right? How can there be a moral line in the sand when the ontology is so fuzzy?

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You could certainly say that Life has begun at that moment. You just can’t say how much or many.

Are you saying that at that point, NO life certainly has begun?
If not so, then you are hiding in obfuscation, “Stoning so that no one can be blamed for the death.”
People get away with it, but it is still murder.
If so, then you are saying, “well I might have killed someone, but we don’t know that for certain.”
But that is called “irresponsible collusion” - “potentially second or third degree murder”.

But yeah, it helps an argument to obfuscate the opponents position as much as possible.
Our current governance does it thousands of times each day - RELIGIOUSLY.

On the other hand, the Jews claimed a large portion of their holocaust victims based on the probability of their being offsprings from those who actually got killed. That got them some extra $200,000,000,000.00 into the till. They wouldn’t like your argument to be applied to them.

5

Take two situations:
In one, two eggs are fertilized. They form a chimera, producing one live birth.
In the other, two eggs are fertilized. One is immediately terminated, the other goes to term, producing one live birth.

Is your contention that in the second case, there has been a second or third degree murder?

I’m more so saying, “I killed something, but it wasn’t a one.”

[EDIT: punctuation]

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If that is your position, then I am saying that you are still clearly committing murder.
The word play wouldn’t help.
People aren’t that picky with their precise definitions on such subjects and you would be in the wrong even if they were.

7

It’s not word play. If anything, it’s ontology play, and the difference changes the answer to the question of whether we can murder people who don’t exist.

I’m saying, because a fertilized egg can create anywhere from a half dozen live births to a fleeting fraction of one, there is no person inherent in it that can be said to be murdered. Just like it’s not murder to use contraception, or for men to have wet dreams and women to menstruate, we’re shedding something that is not yet a person, that can’t possibly be considered a person, so there is no moral consequence to it.

Sure, people “aren’t that picky” about their definitions, but most people are unreflective about their beliefs. If we are reflecting, if we are being picky, the differences matter, they change the moral calculus, and they present real problems for an ontology that says that life begins in a meaningful sense when sperm touches egg.

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I don’t think it would hold up in court.
Life began, you just don’t how much.
You have clearly destroyed life, human life.
You just don’t know how many.
That isn’t a strong argument to make.

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Couldn't a person argue that fuzzy ontology is precisely the reason for the hard moral line?  I.e., something like "This process is murky and can go in many different directions, and since the end result of the process is human life we ought to be as strict about it as possible an forbid tampering".   How would you formulate the opposite in a way that sounds ethical? "This process results in human life, but in the early stages it's murky and can go in several different directions so do whatever you want?"  'Better safe than sorry' might not be the most rigorous moral ethos, but at least it's something. But what's even the tenuous maxim in the other direction? I don't think I've ever heard a "The less certain something is, the more appropriate it is to screw with it" position. 
 Anyway, I tend to agree with you that abortion is not an act morally equivalent to murder, especially at such an early stage.  I also think an act doesn't have to rise to the level of murder to be immoral and worth prohibiting. Besides, if twins are more common than chimeras, aren't you really just making the point that allowing this process is killing [i]even more people[/i] than presumed?

Put another way, if I know there’s a person in a box and I heave it into the sea, ok that’s murder. A 50% chance that there could be a person in a box is still an argument for being careful with boxes, and not in any way a justification for throwing them into the sea.

Also, the chart doesn't show the odds of anything, which seems problematic.  The zygotes function is to become a human person, it's the only thing that does that, and if it succeeds, that's what it will do.  That there's a chance it goes wrong, or that it becomes more than one human person, seems irrelevant, especially if the chance is slim.  Is the flow-chart presenting a "Look how confusing it is, nobody knows how it will turn out!" image when the reality is "97% of the time it goes the exact same way"?
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At least is an argument, James. Why is this “clearly [a] life”? Why do you claim that life began? How is what you’re saying not applicable to other forms of contraception? How is it not applicable to a woman who turns down a guy at a bar only to shed an egg the next time she menstruates? A fertilized egg cannot be equivalent to a human life, because it can create one human, many humans, or only a part of one human. In terms of how we parse the world, to say that it is nonetheless a human life simpliciter is incoherent.

I think you yourself make a case for a similar formulation, that “The less certain something is, the more acceptable it is to screw with it.” Certainly, if the only thing we’re considering is whether or not we should heave the box into the sea for no reason, then a 50% chance should stop us. If someone is pointing a gun at us and telling us to throw the box into the sea or she’ll shoot, and we think she’s 70% serious, then the difference between a 100% chance and a 50% chance changes how we should respond. To put it in more general terms, other considerations matter more when the certainty of any consideration is decreased. If we’re not sure that there’s a life, the choice of the woman matters more in the whole equation of how we should treat it.

I’m also worried that the broader formulation that seems to protect any murky process that results in human life would reach back much to far. As I asked James, how can early abortions be distinguished from contraception? Or from the ability to refuse sex in the first place? We are interfering in a murky process that could result in human life just the same.

I’m also concerned, and this is why I chose the religion and not the sciences forum, with the process by which a human is deemed to have a soul. It will certainly depend on what we mean by soul, and so this question may be naive, but does the fact that the quantity of persons that result form a fertilized egg may change following fertilization mean that the fertilized egg cannot be deemed to have a soul (lest the resulting humans be considered to have only half a soul, or multiple souls). I know there are meanings of soul that treat it as an emerging property, but those meanings don’t seem to have any but pragmatic reasons to oppose abortion, since prior to the soul’s emergence there is no ensouled being killed in the process.

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 No it doesn't, because I'm not culpable of anything if I let her shoot me.  It's not just a math problem.  But leaving that aside to just consider the math, how does your flow chart weight things for probability?  What's actually the chances that twins or chimeras occur, and how do those chances affect the mathematical way you're looking at the problem above?

 See that's what worries me, is that you have percentages in your hypothetical, but you drop them out in your actual argument. I suspect  your argument would be less compelling with those percentages.   Also, I'm not sure what you mean by 'choice' here.  Isn't every ethical decision a choice by definition? I don't think in other sorts of moral cases the desire to choose has much merit.  Do we weigh the wrongness of stealing vs. the value of somebody's choice to steal?  Now, maybe there's some REASON to steal or abort- I can imagine situations in which I'd do either one. But it's got to be about the value of those conditions, not choice in and of itself.

Yeah, that would require an in depth understanding of what a ‘process’ is. Does every single process, from the manufacture of shoes to me getting up in the morning begin like this

Step 1: The Big Bang

Or are there credible ways to distinguish one process from another when valuing them morally? I think most people would sense that the process of convincing somebody to have sex with you is distinct from the process of a zygote becoming a person, but maybe less so with contraception. It’s a good question.

Well… the philosophical objections I’ve read to abortion deal with the fetus’ potential, and the value that comes from potential. I think most of the time the “that glob of goo is a person like my Mom is a person” argument is a strawman, at least when we’re talking zygotes and stuff.

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It’s actually a fine argument. If you catch the embryo before implantation, there is no way to tell if it would have become a human life. Not every embryo implants, and not every implanted embryo becomes a human being. At the very most, that embryo represents potential. If we follow your logic, every time a woman turns down a man for sex, she is destroying a human life.

Here you’re admitting that an embryo becomes, but is not in itself, a human life. So stopping an embryo from implanting is not the same destroying a life. What you’re destroying is potential. We could say the same thing about any means of contraception or refusal to engage in coitus. Yeah, I said coitus. Anyway, that seems to be the point here. Hindering implantation is not the same as destroying a life and is more acceptable for that reason. We destroy massive potential by just being picky about who we have intercourse with.

13

It comports to their definition of “life”… auto-growth to a point of self replicating.
The issue is whether an arrangement of components is self-driven into growth and reproduction or whether any of the components elects to not participate. Murder is an issue of outside interference, thus suicide is not considered murder nor contraception except by the Catholics.

The components that you have described are already “attempting” (known to be headed toward) growth to reproduction, thus the arrangement is already life. Outside interference with life to the point of extinction is murder.

He is specifically referring to a point wherein it is known that life will come about. He just can’t determine which of the variety of options will emerge. That is why I asked concerning that issue first.

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Are you sure? I thought he was talking about hindering implantation. Mono-zygotic twins and chimeras form before implantation.

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Stat;

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OK, put someone else in front of the gun, or make it a train, or make it a situation where you have two boxes and you’re on a sinking ship and you have to heave one box overboard. The point was to have two equal-value possibilities (death of person A or death of person B), but one of them is 70% likely and the other is either 100% likely or 50% likely. I use concrete percentages to emphisize the point. When the likelihood of something happening goes from 100% to 50%, it can have consequences in how we should act.

I then drop the percentages because the change form 100% to not-100% is the change I’m really concerned with. It may be that the most rigorous objection to abortions don’t depend on a zygote being a moral equivalent to a live birth, and the phenomenon I’m talking about may not affect some arguments against abortion. But I don’t think a strong position that literally considers abortion to be equivalent to murder is a strawman, it’s a widely held position, and one sincerely held by at least some seemingly rational and well-informed people.

And for that position, the change from 100% to not-100%, form certainty to fuzziness, is a big change. If, as I am arguing, the existence of even one case of chimerism and monozygotism (you’re right to point out that the likelihood of monozygotic twins is very low, and the likelihood of a chimera is nearly nonexistent, though it’s hard to measure) conclusively demonstrate that a zygote could not be morally equivalent to a new born, that is a change from certainty to fuzziness, and has consequences when we’re balancing between moral values.

When I say ‘choice’, I mean it in terms of the freedom to choose. If someone tells me they’d like to have sex with me, I have the freedom to choose not to for no good reason. There might be people who it would be downright irrational for me to turn down, but I don’t need a reason and the best argument in the world is not compelling. Similarly, if the moral weight of a zygote is nil (for the sake of argument), a woman would not need any particular reason to remove it. She would be able to make that choice, and to take that away from her would be a moral wrong. On the other hand, if a zygote is morally equivalent to a live birth, then it probably outweighs the woman’s freedom to choose.

What the existence of chimerism and monozygotism do is make the situation fuzzy. For the strong position, the change from certainty to uncertainty about moral weight of a zygote is HUGE when it’s balanced against the certain moral weight of the right to choose. It might even come out the same way, but it seems it’s at least an important shift from weighing two certainties, to weighing a certainty of a lesser moral weight against the possibility of a greater moral weight. It starts to matter e.g. just how different the moral weights are, just exactly how certain we are that such a moral weight exists. That is, it gets us into what I think is a more interesting and fruitful discussion about the ethics of abortion than a staunch position that it’s alive and that’s all that matters, EVEN for those who might otherwise take a strong position that what we have in early pregnancy is morally equivalent to what we have in late pregnancy.

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In effect, you are saying that if I shoot a shotgun into a crowd of people, because I don’t know how many people will die or even if they will die for certain, “the situation is fuzzy”, I haven’t committed murder even if one of them actually does die.

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This thread kind of irks me. Cuz the elephant in the room of this thread is hiding the abortion argument. So what’s the actual point? I think we need some women on this thread. Cuz as far as women I’ve been involved with on this issue has been : one dick and no count. Conception begins at erection. So if you’re concerned, keep you dick in your pants. But you can’t, or maybe shouldn’t, take control of women with your dick. Birth is a woman’s body matter.

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Not. At. All. I’m willing to accept that I’m not explaining myself well, and that’s why you think that this is, in effect, what I’m saying, but let me be absolutely clear about whether or not this is the argument I am making, so that it doesn’t have to come up again: It’s not. This is not the argument I’m making.

An important difference between the argument as you have understood it and the argument I’m trying to make is that, in your summary, you have assumed that we’re dealing with a “crowd of people.” I’m talking about the margin between the time prior to a person existing, and the time after which that person can be said to exist. It’s not a question of whether or not some process has been stopped, but whether that process was a person. I hope I am making this distinction clear.

Another way to think of it is this: we’re really not concerned with whether or not it’s murder. Rather, we’re concerned with whether or not it’s a person.

The fuzziness isn’t in the causation, it’s in the nature of the thing being acted upon.

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I agree that it is not the exactly same thing. I am saying that your “argument of fuzziness” is the same.
Obscuring an argument doesn’t actually change the truth of the situation.
And it seems to be that you haven’t really even obscured it that much at all.
You admit that life has already begun. And the type of life is human.
The fuzzy issue of the amount of life, seems irrelevant.