I’d say that the embryo and the placenta are each their own thing, albeit connected by the umbilical cord. I wouldn’t consider any of these three things to individually be “the human”, and nor would I consider all three of them to collectively be “the human”.

But we can even drop consideration of “the human” for the moment and just consider the embryo. A zygote develops into a blastocyst, and then some of its cells develop into a placenta and some into an embryo.

To say that the placenta is part of the embryo rather than that the embryo is part of the placenta is special pleading.

I was just thinking of this the other day. It seems to me that there are many strong arguments and stories in support of the pro-choice position. However, I also find that people often stray away from these and justify abortion in terms that would seem to equally justify infanticide and euthanizing older relatives, or at least abandoning them.

Basically, arguments purely about individual utility or autonomy from responsibility tend to be bad ones. I am not sure the "privacy" framing is particularly useful either. Bodily autonomy, appeals to suffering, social utility, seem better, although pure social utility arguments seem to allow for infanticide and euthanizing the elderly or infirm as well.

I’d say that the embryo and the placenta are each their own thing, albeit connected by the umbilical cord. I wouldn’t consider any of these three things to individually be “the human”, and nor would I consider all three of them to collectively be “the human”.

But we can even drop consideration of “the human” here and just consider the embryo. A zygote develops into a blastocyst, and then some of its cells develop into a placenta and some into an embryo.

To say that the placenta is part of the embryo rather than that the embryo is part of the placenta is special pleading.

These arguments are becoming increasingly convoluted. I'm having trouble understanding them.

Both human zygotes and human embryos are phases or stages of a human being's life. They are not their own entities, but the same entity as it continues to grow over time. All adults were teenagers. All teenagers were infants. All infants were neonates. All neonates were fetuses. All fetuses were zygotes. There is just no way around it.

A human zygote can grow into multiple different living organisms; an embryo, a placenta, and even a second embryo and a second placenta in the case of twins. You treating the zygote as being the same individual as (one of) these later organisms is simply a choice with no physical basis, much like the ship of Theseus.

And it still hasn’t been explained why it is wrong to kill (some of?) these organisms. If you just want to argue that it’s wrong to kill any living organism then there’s less of a problem, but as you specify that it’s wrong to kill humans you need to explain what distinguishes a human from a non-human (and a human from a human organ) and what it is that humans have and that non-humans (and human organs) don’t have that entails that it is wrong to kill humans but not wrong to kill non-humans (or human organs).

As it stands it seems to be that your argument rests on equivocation, ambiguity, and non sequiturs; something like “it’s wrong to kill human children, human children are human, therefore it’s wrong to kill humans, zygotes are human, therefore it’s wrong to kill zygotes.”

"Human" can be predicated of things in different ways. We speak of "human hairs" and "human hands," and surely we can consider both to be properly "human" as opposed to "cat" or "dog" without having to claim that a hand (a part) is a human (whole).

It seems the issue here is a whole that produces something different from itself. The same thing happens with seeds. An acorn is initially part of an oak, it grows from the whole oak. When the acorn falls off the tree it is no longer part of that tree. If the acorn grew into a mature tree we would not say that the second tree was a part of the first or that the two constitute a single tree.

So the question is mereological. Individual animals are generally considered proper beings, wholes. This is because they exhibit a principle of unity and are capable of sustaining their own form. Their organs and limbs are generally considered parts. If I cut my hand off I do not cease to be a man (although my hand remains a human one). My hand does cease to be part of a man, part of a self-sustaining unity.

A placenta is an organ. A featus is not an organ. It has a substantial unity. Human is more rightly predicated of a featus because it is a unified being/member of a species, not an organ.

A placenta is an organ. A featus is not an organ. It has a substantial unity. — Count Timothy von Icarus

What is "substantial unity"? Why does it have moral relevance such that it's wrong to kill something with "substantial unity" (or at least some things; is it wrong to kill flies?) but not wrong to kill something without it?

and are capable of sustaining their own form — Count Timothy von Icarus

I'm not sure what this means. Do you mean that it can survive on its own? Because a (young) foetus certainly can't. If it were that simple we'd just remove them without killing them and put them in an incubator.

What does it mean to be a member of the human species? Is the placenta a human being? It has human DNA, is a living organism, and develops from the blastocyst. Is the heart a human being?

This is basic biology. It is a member of the human species if it that certain kind of animal: homo sapien.

A member of a species has to be an organism, taken as a whole, of that species: so obviously, e.g., a human heart is not a human being.

If a blastocyst separates into twins, is that one human being becoming two?

Technically, yes. Just like how, likewise, siamese twins are one human being. I think you may be confusing persons with human beings—e.g., siamese twins are one human being, but (usually) two persons.

Not to the naked eye---so?!? The point is not whether or not one can tell if it is a human being: the point is whether or not a fertilized egg is a human being.

Having a substantial unity need not imply any moral valence. It just means that something is a proper whole with proper parts.

Life is probably the best example. No lifeform is capable of sustaining itself in isolation, but obviously plants and animals are self-organizing and self-sustaining in ways that rocks, storm systems, stars, etc. are not.

Do you mean that it can survive on its own? Because a (young) foetus certainly can't

Sure, but this is true of children till a fairly late age, the elderly, and the infirm. We might even add most adult humans if "on their own" means something like "being dumped off in the wilderness."

That's why I would tend to locate the most salient fact as the fact that a featus can't exist outside another person's body. Of course, an elderly parent might not be able to survive without their child's body in a way that encroaches on one's lifestyle even more than pregnancy generally does, so I am not sure if the inside/outside distinction totally resolves the issue, but it does seem particularly relevant.

I guess another example would be that acorns are not oaks in an unqualified sense, but they are certainly oaks in some sense.

But a featus seems more analogous to a sapling or sprout to me, and it seems harder to claim that a sapling is not an oak.

Frogs and caterpillars are another good one. A tadpole is a frog in an important sense.

A placenta isn't a living organism. It's an organ. But yes, an individual zygote can split into two individuals. It's why identical twins are identical, or mirror images of each other. In any case, both can trace their history and existence to the one zygote.

Will you state that no human being was ever a zygote? The zygote is just the brief beginnings of a process that does not end until death. The zygote is alive, belongs to the human species, and is an organism. Therefor it is a human being. If not, then what is it?

A member of a species has to be an organism, taken as a whole, of that species — Bob Ross

This is circular.

This is basic biology. It is a member of the human species if it that certain kind of animal: homo sapien. — Bob Ross

Well, I wouldn't say that homo sapiens are single-celled animals.

A placenta isn't a living organism. It's an organ. — NOS4A2

What do you think a living organism is?

But yes, an individual zygote can split into two individuals. It's why identical twins are identical, or mirror images of each other. In any case, both can trace their history and existence to the one zygote. — NOS4A2

Yes, but importantly each twin is not the same individual as the other and so they cannot both be the same individual as the zygote. Therefore either just one of them is the same individual as the zygote (which is special pleading) or neither is.

The fact that they can "trace their history and existence" to the zygote does not entail that they and the zygote are the same individual.

If not, then what is it? — NOS4A2

A eukaryotic cell containing (usually) 24 distinct chromosomes.

What do you think a living organism is?

Basically any living thing.

Yes, but importantly each twin is not the same individual as the other and so they cannot both be the same individual as the zygote. Therefore either just one of them is the same individual as the zygote (special pleading) or neither is.

The fact that they can "trace their history and existence" to the zygote does not entail that they and the zygote are the same individual.

Sure it does. The facts indicate that they were both the same zygote.

A eukaryotic cell containing 24 distinct chromosomes.

And no human being was every a eukaryotic cell containing 24 distinct chromosomes?

Basically any living thing. — NOS4A2

A placenta is a living thing.

Sure it does. The facts indicate that they were both the same zygote. — NOS4A2

The zygote grew into them, but they are not the same thing, as proven by the fact that each twin is not the same thing as the other.

As it stands you're saying that A is the same individual as C, that B is the same individual as C, but that A is not the same individual as B. That's a contradiction.

And no human being was every a eukaryotic cell containing 24 distinct chromosomes? — NOS4A2

This is such an ambiguous question. Glass used to be sand, but sand isn't glass. Butterflies used to be caterpillars, but caterpillars aren't butterflies. My house used to be a pile of bricks, but that pile of bricks wasn't my house.

Your reasoning that "A used to be B, therefore A and B are the same individual" is fallacious. Identity doesn't work that way.

It just means that something is a proper whole with proper parts. — Count Timothy von Icarus

Why does a placenta not count as a "proper whole with proper parts"?

No lifeform is capable of sustaining itself in isolation, but obviously plants and animals are self-organizing and self-sustaining in ways that rocks, storm systems, stars, etc. are not. — Count Timothy von Icarus

Yes, but let's take different forms of living organism; bacteria, grass, zygote, placenta, foetus. Which of these count as a "unity" and why only them?

Why does a placenta not count as a "proper whole with proper parts"?

For the same reason a hand is part of a person and not a person.

Yes, but let's take different forms of living organism; bacteria, zygote, placenta, foetus

One of these is not like the others; a placenta is an organ not an organism. A liver is likewise not an organism.

A placenta is a living thing.

A placenta is an organ of a living thing.

The zygote grew into them, but they are not the same thing, as proven by the fact that each twin is not the same thing as the other.

As it stands you're saying that A is the same individual as C, that B is the same individual as C, but that A is not the same individual as B. That's a contradiction.

They were the same thing at an earlier stage in their development. It is no contradiction if C splits into A and B.

This is such an ambiguous question. Glass used to be sand, but sand isn't glass. Butterflies used to be caterpillars, but caterpillars aren't butterflies. My house used to be a pile of bricks, but that pile of bricks wasn't my house.

Your reasoning that "A used to be B, therefore A and B are the same individual" is fallacious. Identity doesn't work that way.

A used to be A, is my reasoning. It’s a continuum. A doesn’t switch identities at some arbitrary point. You’re the one positing B.

I believe I've missed a joke.

A placenta is an organ of a living thing. — NOS4A2

And it is a living thing.

They were the same thing at an earlier stage in their development. It is no contradiction if C splits into A and B.

...

A used to be A, is my reasoning. It’s a continuum. A doesn’t switch identities at some arbitrary point. You’re the one positing B. — NOS4A2

If twin A is the same individual as the zygote and if twin B is the same individual as the zygote then twin A is the same individual as twin B.

Twin A is not the same individual as twin B.

Therefore twin A is not the same individual as the zygote and/or twin B is not the same individual as the zygote.

One of these is not like the others; a placenta is an organ not an organism. A liver is likewise not an organism. — Count Timothy von Icarus

So your definition of an organism is something like "two or more organs keeping each other alive" (although this doesn't account for single-celled organisms)?

The human body contains 78 organs, but with only 5 considered "vital": brain, heart, lungs, liver, and kidneys.

So let's take organs away, keeping the rest of the body alive through artificial means. First the skeleton, then the skin, and then everything else until just the vital organs are left. Still human? Still the same individual?

Now let's remove the heart, lungs, liver, and/or kidneys (and again, keeping whatever is left alive through artificial means). Still human? Still the same individual? And to Count Timothy: would a living brain on its own count as an organism, or just an organ?

But what if rather than removing the heart, lungs, liver, and/or kidneys we remove the brain. Still human? Still the same individual?

I think there's certainly something special about the brain. Whereas removing other organs and keeping the remaining organs alive artificially doesn't count as killing the human/individual, removing the brain would. This is why I don't think it matters much if the foetus is killed before the brain has sufficiently developed.

And it is a living thing.

It isn’t. It does not have any means of reproducing, is not predisposed to functioning on its own, has no metabolism, etc. etc. etc. Given the diversity of life, "organism" is a tricky word to pin down, but an organ doesn't have a single quality of an organism.

If twin A is the same individual as the zygote and if twin B is the same individual as the zygote then twin A is the same individual as twin B.

Twin A is not the same individual as twin B.

Therefore twin A is not the same individual as the zygote and/or twin B is not the same individual as the zygote.

If twin A was the same individual as the zygote and if twin B was the same individual as the zygote then twin A was the same individual as twin B.

Twin A was the same individual as twin B.

Therefore twin A was the same individual as the zygote and/or twin B was the same individual as the zygote.

Banno, my position is that a blastocyst is a human being, not that it is a person. Can you please critique that instead of a straw man? I want to hear why you don't think that the blastocyst is alive, a separate alive entity than the mother, and is a member of the human species. It is really weird, to me, to say that it is not a new member of the human species. — Bob Ross

Ok, then: A blastocyst is not a human being. The blastocyst is alive. It can be considered as a seperate entity - it might be moved to another host, for example. It has human DNA and so on, but it is no more a "member of the human species" than is your finger.

All this is insubstantial in the argument I presented to you. We have on the one hand a woman, perhaps a nurse, perhaps a CEO, perhaps a sister, mother, daughter, perhaps a care giver or volunteer. Someone who can express their needs, who makes plans and seeks to fulfil them and who has a place in our world.

We have on the other hand, a group of cells.

That you value those cells over the person who must carry them is heinous.

That you value those cells over the person who must carry them is heinous. — Banno

Yes, pro-life people are heinous. They're like those creatures from the Lord of the Rings who are some kind of supernatural evil. They never bathe and they have fangs and they're all ugly.

The point is not whether or not one can tell if it is a human being — Bob Ross

I think we should be able to tell if something is a human being if we’re calling it a human being.

All this is insubstantial in the argument I presented to you. We have on the one hand a woman, perhaps a nurse, perhaps a CEO, perhaps a sister, mother, daughter, perhaps a care giver or volunteer. Someone who can express their needs, who makes plans and seeks to fulfil them and who has a place in our world.

We have on the other hand, a group of cells.

That you value those cells over the person who must carry them is heinous. — Banno

:up:

It isn’t. It does not have any means of reproducing, is not predisposed to functioning on its own, has no metabolism, etc. etc. etc. Given the diversity of life, "organism" is a tricky word to pin down, but an organ doesn't have a single quality of an organism. — NOS4A2

A placenta is no less alive than a zygote.

If twin A was the same individual as the zygote and if twin B was the same individual as the zygote then twin A was the same individual as twin B.

Twin A was the same individual as twin B.

Therefore twin A was the same individual as the zygote and/or twin B was the same individual as the zygote. — NOS4A2

"Was" and "is" do not mean the same thing. Each twin was a zygote. But your conclusion that the zygote "will be the same particular entity, a human being, from fertilization onward" is both invalid and false. It cannot be the same particular entity as both twins that develop from it.

On the other side there are chimeras, where two zygotes fuse into one. To say that the eventual baby is the same individual/entity as both the zygotes that precede it is as nonsense as saying that a zygote is the same individual/entity as the sperm and the ovum.

You are saying (or at least it appears that way) that a zygote is a human being because it turns into a human being. But unless you can give some definition/explanation of how to identify a human being this reasoning is circular and vacuous. And as you said elsewhere

No measurable property called “personhood” appears or disappears in any given human being. Therefor no one can pick and choose with any certainty when one is or isn’t a person. — NOS4A2

Does your reasoning rely on some distinction between “person” & “human being”?

You are saying (or at least it appears that way) that a zygote is a human being because it turns into a human being. But unless you can give some definition/explanation of how to identify a human being this reasoning is circular and vacuous. And as you said elsewhere

I’m saying that a zygote is the earliest stages of a human being’s life. It doesn’t turn into something else. We can identify him as a human being simply because he has human parents. On top of that there is zero evidence that it is some other species, alien, or life form.

Does your reasoning rely on some distinction between “person” & “human being”?

I don’t distinguish the two, personally.