Embryonic and adult stem cells each had advantages and disadvantages.

At the embryonic stage, stem cells have the ability to differentiate into different types of cells and to duplicate themselves (differentiation and self renewal). These characteristics provide the theoretical potential to repair nearly any body part.

However, embryonic stem cells have failed to provide actual therapies and are unlikely to do so in the foreseeable future because scientists have been unable to program them to become a single cell type and to keep the recipient body's immune system from killing them.

Adult stem cells are a mirror of embryonic stem cells. Adult stem cells have lost the characteristics of differentiation and self renewal through maturity. Instead, adult stem cells can only create one type of cell. However, adult stem cells are taken from one's own body and are not rejected by the immune system. As a result, adult stem cells are being successfully used in a growing range of medical therapies.

In a potentially enormous breakthrough, two teams of scientists have succeeding in creating Induced Pluripotent Stem Cells, which are adult stem cells which are genetically modified to regain the characteristics of differentiation and self renewal. If this research pans out, we will now have the ability to use our own adult stem cells which are accepted by our body's immune system with all the potential advantages of differentiation and self renewal.

If Induced Pluripotent Stem Cell research pans out, embryonic stem cell research should be halted.

Potential embryonic stem cell therapies always had enormous sourcing problems. If the theory pans out and scientists can develop a wide variety of medical therapies, making these therapies available globally will require a massive conception of human embryos to be killed and harvested. The problems scientists are having using a limited number of embryo lines for small scale research would be multiplied exponentially if any therapy ever pans out.

"Big Pharma" will either need women to sell their eggs to conceive an ongoing supply of fresh human embryos to kill and harvest to supply the new demand or this business will need to clone the necessary human embryos to avoid purchasing female eggs. Even those who casually dismiss the value of human beings at the embryonic stage should be more than a little disturbed by this prospective brave new world.

With the advent of Induced Pluripotent Stem Cell, there is simply no reason to take this road.
 

"Embryos lack any neuronal development, so they can’t be conscious of their existence, experience their environment, feel pain, or imagine the future."

Neither can the reversibly comotose, but they're obviously people.

"Embryos in a Petri dish can't become people without substantial human assistance."

I agree that embryos can't perform the behaviors that distinguish people from other forms of life without substantial assistance. But neither can lots of adults (e.g., many of the reversibly comatose).

"[N]or are they even likely to become people if they are placed in a womb."

But someone with only a 1% chance of surviving long enough to wake up from his coma is still a person. It's not okay to use his body for research.

"The broad view of potentiality that would justify a comparison of embryos and people would also suggest that we ascribe significant moral value to individual egg and sperm cells."

No, because egg and sperm cells become adults only though a substantial change (at conception). The embryo becomes an adult epigenetically (that is, by the internally-directed development of a potency that is already fully present at conception), without becoming a different sort of substance. I think having the epigentic primordium of an actively functioning human brain is enough for personhood.
 

I address the ethical issues over at my blog. It answers prety much all of "Bart"'s nonsense.

Having "Bart" lecture us on stem cell research when he's a freakin' lawyer that can't even cite Supreme Court cases correctly, of course, is cause for projectile emesis.

Where he got this crapola is beyond me:

Adult stem cells are a mirror of embryonic stem cells. Adult stem cells have lost the characteristics of differentiation and self renewal through maturity. Instead, adult stem cells can only create one type of cell.

Can I just say that this is balderdash?!?!?

And this too:

However, embryonic stem cells have failed to provide actual therapies and are unlikely to do so in the foreseeable future because scientists have been unable to program them to become a single cell type and to keep the recipient body's immune system from killing them.

IOW, a pile'o'crap. Either he mindlessly and ignerrently cribbed it from some RW cite, or he's making shite up.

Now this is more nonsense:

In a potentially enormous breakthrough, two teams of scientists have succeeding in creating Induced Pluripotent Stem Cells, which are adult stem cells which are genetically modified to regain the characteristics of differentiation and self renewal.

Nah. They used skin cells. Not "adult stem cells".

See my blog article for the details.

Potential embryonic stem cell therapies always had enormous sourcing problems. If the theory pans out and scientists can develop a wide variety of medical therapies, making these therapies available globally will require a massive conception of human embryos to be killed and harvested.

OK, "Bart", where'd you cut'n'paste this agitprop from?

Cheers,
 

Link lost, sorry. Here's my blog post on this.

Cheers,
 

"Embryos lack any neuronal development, so they can’t be conscious of their existence, experience their environment, feel pain, or imagine the future."

Neither can the reversibly comotose, but they're obviously people.

Suppose we change the subject of the original sentence so that it now reads, "Rocks lack any neuronal development, so they can't be conscious of their existence, experience their environment, feel pain, or imagine the future."

Your response to this would be an obvious non-sequitur. In order to make your response meaningful, you have to show some substantial similarity between a blastocyst and a person. Otherwise, your argument is no more persuasive than it would be for the rock.

I agree that embryos can't perform the behaviors that distinguish people from other forms of life without substantial assistance.

This is non-responsive to the point made (that embryos in a petri dish cannot become human beings). The comatose need not "become" persons, they already are.

But someone with only a 1% chance of surviving long enough to wake up from his coma is still a person.

Again, this is non-responsive, as evident by the word "still". Yes, the comatose are "still" persons; embryos are "not yet and may never be".

egg and sperm cells become adults only though a substantial change (at conception).

This is also true of blastocysts, which become adults only through substantial changes.

The embryo becomes an adult epigenetically (that is, by the internally-directed development of a potency that is already fully present at conception)

This is incorrect in at least two ways. First, the development of an embryo is NOT exclusively internally self-directed. In fact, the developmental process depends in substantial part on the environment of the womb and the signals it receives from that environment. It's a feedback system. If this weren't true, we wouldn't need wombs.

Second, a "potency" is, by definition, not "fully present" at conception. It's a potential, not an actual.

I think having the epigentic primordium of an actively functioning human brain is enough for personhood.

Not to sound harsh, but I don't believe you really think this. I've never heard of anyone, for example, who holds funerals for blastocysts which fail to implant.
 

arne langsetmo said...

I address the ethical issues over at my blog. It answers prety much all of "Bart"'s nonsense.

Actually, I barely address the ethics of killing human embryos for their parts and concentrate mostly on the science. The ethics are self explanatory.

BD: Adult stem cells are a mirror of embryonic stem cells. Adult stem cells have lost the characteristics of differentiation and self renewal through maturity. Instead, adult stem cells can only create one type of cell.

Can I just say that this is balderdash?!?!?

Barrilleaux B, Phinney DG, Prockop DJ, O'Connor KC (2006). "Review: ex vivo engineering of living tissues with adult stem cells". Tissue Eng. 12 (11): 3007-19.

BD: However, embryonic stem cells have failed to provide actual therapies and are unlikely to do so in the foreseeable future because scientists have been unable to program them to become a single cell type and to keep the recipient body's immune system from killing them.

IOW, a pile'o'crap. Either he mindlessly and ignerrently cribbed it from some RW cite, or he's making shite up.

Wu DC, Boyd AS, Wood KJ (2007). "Embryonic stem cell transplantation: potential applicability in cell replacement therapy and regenerative medicine". Front. Biosci. 12: 4525-35.

In a potentially enormous breakthrough, two teams of scientists have succeeding in creating Induced Pluripotent Stem Cells, which are adult stem cells which are genetically modified to regain the characteristics of differentiation and self renewal.

Nah. They used skin cells. Not "adult stem cells".

Mr. Science, are you claiming that you cannot derive adult stem cells from this source? Try reading...

Nature 447, 618-619 (7 June 2007)

Thomson JA, Yu J, et al. | Induced Pluripotent Stem Cell Lines Derived from Human Somatic Cells | Science DOI: 10.1126/science.1151526

Yamanaka S, et al. | Induction of Pluripotent Stem Cells from Adult Human Fibroblasts by Defined Factors | doi:10.1016/j.cell.2007.11.019
 

If I may make a humble suggestion, while the scientific discussion is fascinating -- I love Bart's methodology of just citing papers as if they were cases -- the science has been discussed at length on various science blogs, Pharyngula, for one.
 

Mark: "[Y]ou have to show some substantial similarity between a blastocyst and a person. Otherwise, your argument is no more persuasive than it would be for the rock."

I think the comatose person would be just as good a counterexample to the premise (2) in this argument:

(1) rocks aren't conscious,
(2) consciousness is required for personhood, so
(3) rocks aren't persons.

Obviously, (3) is true, but that doesn't mean that any argument in its favor is a proper one.

At any rate, "substantial similarity"--or rather, substantial identity--between the early embryo and the resulting adult seems pretty plausible to me. The embryo produces the adult by an internally directed epigenetic process, without ever turning into a different substance.

Me: "I agree that embryos can't perform the behaviors that distinguish people from other forms of life without substantial assistance."

Mark: "This is non-responsive to the point made (that embryos in a petri dish cannot become human beings)."

What I'm trying to respond to is the suggestion that the lack of a guaranteed future for the embryo supports Korobkin's earlier statement: "Early-stage embryos and people are different in the ways important to the determination of moral status." I took Karobkin's statement that the embryo requires substantial assistance to be a consideration in favor of that moral claim about the embryo, and offered the comatose as a counterexample to the apparent inference from the need for substantial assitance to negligible moral status. Karobkin concedes, moreover, that the embryo does sometimes become an adult person--his point is that that process requires assistance.

Mark: "[T]he development of an embryo is NOT exclusively internally self-directed. ... If this weren't true, we wouldn't need wombs."

That can't be right. We need food and air, but food and air don't direct our development.

Mark: "[A] 'potency' is, by definition, not 'fully present' at conception. It's a potential, not an actual."

I don't understand what you're saying. A potency isn't actualized, but it can really exist at a particular point in time before then. That's all I'm saying about the potency--that it's all there at conception, not that it's fully actualized.

Me: "I think having the epigentic primordium of an actively functioning human brain is enough for personhood."

Mark: "I don't believe you really think this."

No, I do. "[N]o fakery here. No insincerity either."

"I've never heard of anyone, for example, who holds funerals for blastocysts which fail to implant."

But surely our practices of mourning can't tell us who is and isn't a person. To mourn a person specifically, we need information about a person's distinctive traits that we lack regarding embryos.
 

Prof. Korobkin did not just say that a blastocyte lacks consciousness and self-awareness. He said a blastocyte lacks neuronal development. A comatose person has full neuronal development.

If a comatose person only has a 1% chance of recovery, it is my understanding that it would be ethically permissible to withdraw life support and, if the comatose person is an organ donor and has any acceptable organs, to harvest them.
 

That can't be right. We need food and air, but food and air don't direct our development.

Actually, food and air DO, in part, direct our development. More significantly, the environment of the womb does much more than supply food and water. There's a complicated signaling back and forth between mother and embryo which substantially directs the development process. It is just plain wrong to claim that development is exclusively internally directed.

To mourn a person specifically, we need information about a person's distinctive traits that we lack regarding embryos.

And it's precisely that lack -- not of information, but of any actual "traits" -- which makes most of us doubt that blastocysts are persons.
 

Enlightened layperson: "Prof. Korobkin did not just say that a blastocyte lacks consciousness and self-awareness. He said a blastocyte lacks neuronal development. A comatose person has full neuronal development."

Not full development, since the comatose brain isn't functioning to produce consciousness. But I don't see why the presence of neurons as such should be morally significant when they aren't functioning. An neuron-less ET who behaved like a human adult would still be a person, for instance. Neurons are only morally significant insofar as they support future behavior of the sort that distinguishes persons--neurons that won't function in the future aren't enough. The reversibly comatose person has the physical basis for a future functioning brain, given nutrition and certain sorts of substance-preserving assistance. The embryo likewise has the physical basis for--that is, the epigenetic primordium of--a future functioning brain, given nutrition and certain sorts of substance-preserving assistance.

Enlightened layperson: "If a comatose person only has a 1% chance of recovery, it is my understanding that it would be ethically permissible to withdraw life support and, if the comatose person is an organ donor and has any acceptable organs, to harvest them."

Doesn't seem right to me. Surely not if it's 20% or 50%, though, right?

Mark: "[F]ood and air DO, in part, direct our development."

That can't be right, can it? Certainly food and air don't change us from one substance into another one.

Mark: "There's a complicated signaling back and forth between mother and embryo which substantially directs the development process. It is just plain wrong to claim that development is exclusively internally directed."

When I say that development of the embryo into an adult is internally directed, I mean that the embryo possesses integral organic functioning; the embryo in gaining new organs like a brain never turns into a different substance during the process. Maternal signaling may affect the timing of how the embryo develops, but the genetic information determining how to build organs like the brain comes from within the embryo's own material.

Me: "To mourn a person specifically, we need information about a person's distinctive traits that we lack regarding embryos."

Mark: "And it's precisely that lack -- not of information, but of any actual 'traits' -- which makes most of us doubt that blastocysts are persons."

I'm not sure what you mean here. The embryo has plenty of traits. It has the ability to direct the building of a brain. Our dispute is over the moral significance of that property, not whether the embryo has any properties at all. Here, I'm just saying that there are perfectly sensible explanations for the lack of embryonic funerals besides the lack of embryonic personhood.
 

I'm not sure what you mean here. The embryo has plenty of traits.

What I meant was that blastocysts (not the same as embryos, btw) lack the traits of persons.

That can't be right, can it? Certainly food and air don't change us from one substance into another one.

No, they can't change the underlying substance. But food and other essentials very much do affect the development in utero. Just to give the simplest example, they affect later height and weight. But they also can affect more fundamental things. Lack of vitamins, for example, can cause a number of birth defects.

Maternal signaling may affect the timing of how the embryo develops, but the genetic information determining how to build organs like the brain comes from within the embryo's own material.

First off, timing is absolutely critical to development. It's a sine qua non, in fact. A fertilized egg won't develop at all outside the womb. That's not just lack of nutrition, it's also lack of the (usually) hormone signals which affect development.

Second, the hormonal environment within the womb has a profound effect on the developmental process. Just for example, maternal levels of testosterone affect such fundamental personal characteristics as sexual identity and behavior. It's also likely that maternal testosterone affects things like spatial reasoning ability.
 

"Bart" DePalma cut'n'pasted from somewhere (tell us where, "Bart", because you don't know a blastocele from an invagination):

Embryonic and adult stem cells each had advantages and disadvantages.

Oh, really?!?!? And your pubslihed, peer-reviewed papers in developmental biology are?!?!?

At the embryonic stage, stem cells have the ability to differentiate into different types of cells and to duplicate themselves (differentiation and self renewal)....

The most salient feature of stem cells is not these two capacities, but rather that they have not yet differentiated, and thus committed, to a certain type of tissue.

... These characteristics provide the theoretical potential to repair nearly any body part.

Possibly. The most interesting part is that the earlier on in development you can get them (and the less differentiated they are), the wider the range of tissue types you bac coax out of them. For instance, blood stem cells can (generally) be coaxed into making blood cells only, but embryonic stem cells can form mesodermal tissues (muscle, cartilage, bone), ectodermal tissues (skin, nerves), and endodermal tissues (glands).

However, embryonic stem cells have failed to provide actual therapies ...

Actually, there's no stem cells of any kind have have been approved as "actual therapies". That isn't the point. What has been shown for embryonic stem cells is the ability for these cells to differentiate and act in ways that may eventually become beneficial in treatment. See here and here, just for starters.

... and are unlikely to do so in the foreseeable future because scientists have been unable to program them to become a single cell type and to keep the recipient body's immune system from killing them.

This is just totally inaccurate. That is to say, wrong.

Adult stem cells are a mirror of embryonic stem cells....

Huh?!?!? WTF is a "mirror"? This is just pseudoscientific (if that) blather.

... Adult stem cells have lost the characteristics of differentiation and self renewal through maturity.

Huh?!?!? Wrong. Adult stem cells can (and do) also differentiate into the various specialized cells that the body needs. It is in fact essential to health that blood stem cells do so. Not to mention, they have a capacity for "self renewal". Where "Bart" got this totally wrong garbage is beyond me. Not from any scientific article, I can tell you.

... Instead, adult stem cells can only create one type of cell.

Once again, wrong.

... However, adult stem cells are taken from one's own body and are not rejected by the immune system.

This is one advantage. They are immunologically self-similar and avoid MHC incompatibility problems. But nonetheless, non-autologous transplants are done routinely in medicine.

... As a result, adult stem cells are being successfully used in a growing range of medical therapies.

Where?!?!?

... In a potentially enormous breakthrough, two teams of scientists have succeeding in creating Induced Pluripotent Stem Cells, which are adult stem cells which are genetically modified to regain the characteristics of differentiation and self renewal....

And carcinogenicity....

... If this research pans out, we will now have the ability to use our own adult stem cells which are accepted by our body's immune system with all the potential advantages of differentiation and self renewal.

This, of course, ignores the fact that some of the therapies thought to be amenable to stem-cell transplants are for precise reason of introducing non-autologous cells because they don't have the genetic defect that the individual is suffering from and which is sought to be treated.

If Induced Pluripotent Stem Cell research pans out, embryonic stem cell research should be halted.

Why?

Potential embryonic stem cell therapies always had enormous sourcing problems....

Why?

... If the theory pans out and scientists can develop a wide variety of medical therapies, making these therapies available globally will require a massive conception of human embryos to be killed and harvested....

Why? For current research needs, far more embryos exist just as left-overs from IVF than can ever be used.

... The problems scientists are having using a limited number of embryo lines for small scale research would be multiplied exponentially if any therapy ever pans out.

Huh?!?!? Why? Explain the "problem" here, Dr. "Bart".

"Big Pharma" will either need women to sell their eggs to conceive an ongoing supply of fresh human embryos to kill and harvest to supply the new demand ...

Since when? Say, "Bart", you do know, don't you, that stem cell lines are self-perpetuating (albeit it's not known yet how many generations are possible)?

... or this business will need to clone the necessary human embryos to avoid purchasing female eggs....

Huh?!?!? Why?

... Even those who casually dismiss the value of human beings at the embryonic stage should be more than a little disturbed by this prospective brave new world.

Go see my blog, "Bart". You'll receive enlightenment.

With the advent of Induced Pluripotent Stem Cell, there is simply no reason to take this road.

Yes, there is. I mentioned one above (and that's just the obvious one.

Cheers,
 

Mark: "What I meant was that blastocysts (not the same as embryos, btw) lack the traits of persons."

I'm using "embryo" to refer to the stage that begins at conception. I gather there's a difference of opinion between the dictionaries; compare here and here. The blastocyst is only a later stage, though, so it's not the best term to use either for the stage beginnig at conception. To talk about that stage beginning at conception, we can use the terms zygote or conceptus--I'll go with conceptus, since it lasts longer.

I'm not following your argument now, though. We're talking about this statement of yours: "And it's precisely that lack -- not of information, but of any actual 'traits' -- which makes most of us doubt that blastocysts are persons." And so you now say that what makes you think the conceptus isn't a person is that it lacks the traits of persons. Obviously personhood depends on having particular properties, and you think the conceptus lacks them. But I'm still not sure what you think those properties are, other than the property of being mourned at a funeral.

Mark: "[T]iming is ... a sine qua non."

Granted. But maternal signals aren't where the conceptus gets the information about how to build a brain. That's what the conceptus does on its own, with no substance-transforming intervention from the outside.

Mark: "[F]ood and other essentials ... affect later height and weight."

Mark: "[H]ormonal environment within the womb has a profound effect on ... characteristics as sexual identity and behavior ... [and likely] things like spatial reasoning ability."

Also granted. But as you concede, maternal hormones don't turn the conceptus into a different substance. That's all I need in order to answer Korobkin's what-about-personhood-for-the-ovum-or-sperm argument. Fertilization uncontroversially transforms sperm and egg cells into a different substance.
 

"Bart" DePalma incomprehendingly cuts'n'pastes some more:

["Bart"]: Adult stem cells are a mirror of embryonic stem cells. Adult stem cells have lost the characteristics of differentiation and self renewal through maturity. Instead, adult stem cells can only create one type of cell.

[Arne]: Can I just say that this is balderdash?!?!?

Barrilleaux B, Phinney DG, Prockop DJ, O'Connor KC (2006). "Review: ex vivo engineering of living tissues with adult stem cells". Tissue Eng. 12 (11): 3007-19.

Quote from the paper saying this, please.

["Bart"]: However, embryonic stem cells have failed to provide actual therapies and are unlikely to do so in the foreseeable future because scientists have been unable to program them to become a single cell type and to keep the recipient body's immune system from killing them.

[Arne]: IOW, a pile'o'crap. Either he mindlessly and ignerrently cribbed it from some RW cite, or he's making shite up.

Wu DC, Boyd AS, Wood KJ (2007). "Embryonic stem cell transplantation: potential applicability in cell replacement therapy and regenerative medicine". Front. Biosci. 12: 4525-35.

Quote from the paper saying this, please.

["Bart"]: In a potentially enormous breakthrough, two teams of scientists have succeeding in creating Induced Pluripotent Stem Cells, which are adult stem cells which are genetically modified to regain the characteristics of differentiation and self renewal.

[Arne]: Nah. They used skin cells. Not "adult stem cells".

Mr. Science, are you claiming that you cannot derive adult stem cells from this source? Try reading...

I said they created "pluripotent stem cells" (OIW an analogue of "embryonic stem cells", whose primary characteristic and distinguishing feature compared to adult stem cells is the pluripotency) from skin cells.

That's what they did. You said "two teams of scientists have succeeding in creating Induced Pluripotent Stem Cells, which are adult stem cells which are genetically modified to regain the characteristics of differentiation and self renewal." That's not true. They didn't modify "adult stem cells". They modified skin cells.

Nature 447, 618-619 (7 June 2007)

OK, once again, where's the money quote?

Thomson JA, Yu J, et al. | Induced Pluripotent Stem Cell Lines Derived from Human Somatic Cells | Science DOI: 10.1126/science.1151526

Yamanaka S, et al. | Induction of Pluripotent Stem Cells from Adult Human Fibroblasts by Defined Factors | doi:10.1016/j.cell.2007.11.019

Yeah. I get Science magazine. Note they said "somatic cells". Not "adult stem cells". I'm not the one confoozed here. I know what they did. I don't think you do, so I suggest you stop trying to play "Dr. Bart" and lecture us on science; you're sufficiently error-prone when you lecture us on your own supposed vocation.

Now fess up; what agit-prop site have you been cut'n'pasting from?

Cheers,
 

More comment from Science:

Science 23 November 2007:
Vol. 318. no. 5854, pp. 1224 - 1225
DOI: 10.1126/science.318.5854.1224

Prev | Table of Contents | Next
News of the Week
DEVELOPMENTAL BIOLOGY:
Field Leaps Forward With New Stem Cell Advances
Gretchen Vogel and Constance Holden

For a year and a half, stem cell researchers around the world have been racing toward a common goal: to reprogram human skin cells directly into cells that look and act like embryonic stem (ES) cells. Such a recipe would not need human embryos or oocytes to generate patient-specific stem cells--and therefore could bypass the ethical and political debates that have surrounded the field for the past decade.

The pace was set in June 2006, when Shinya Yamanaka of Kyoto University in Japan reported that his group had managed the feat in mice by inserting four genes into cells taken from their tails (Science, 7 July 2006, p. 27). Those genes are normally switched off after embryonic cells differentiate into the various cell types. The pace picked up in June this year, when Yamanaka and another group showed that the cells were truly pluripotent (Science, 8 June, p. 1404).

Now the race has ended in a tie, with an extra twist: Two groups report this week that they have reprogrammed human skin cells into so-called induced pluripotent cells (iPCs), but each uses a slightly different combination of genes. In a paper published online in Cell on 20 November, Yamanaka and his colleagues report that their mouse technique works with human cells as well. And in a paper published at the same time online in Science (www.sciencemag.org/cgi/content/abstract/1151526), James Thomson of the University of Wisconsin, Madison, and his colleagues report success in reprogramming human cells, again by inserting just four genes, but two of the genes are different from those Yamanaka uses.

Among stem cell scientists, the human cell reprogramming feats have somewhat overshadowed another major advance reported online in Nature last week: A team at the Oregon National Primate Research Center has officially become the first to obtain embryonic stem cells from cloned primate embryos, an advance that brings therapeutic cloning closer to reality for humans. Taken together, these feats suggest that scientists are getting very close to uncovering the secret of just what occurs in an oocyte to turn back the clock in the DNA of a differentiated cell.

The two human reprogramming papers could help solve some of the long-standing political and ethical fights about stem cells and cloning. The technique produces pluripotent cells, cells with the potential to become any cell type in the body, without involving either embryos or oocytes--two sticking points that have made embryonic stem cell research so controversial. Ian Wilmut of the University of Edinburgh, U.K., says that once he learned of Yamanaka's mouse work, his lab set aside its plans to work on human nuclear transfer experiments, otherwise known as research cloning. The new work now confirms that decision, he says. Direct reprogramming to iPCs "is so much more practical" than nuclear transfer, he says.

Figure 1 Full of potential. Human induced pluripotent cells form teratomas, tumors with multiple cell types.

CREDIT: J. YU ET AL., SCIENCE

In the new work, Yamanaka and his colleagues used a retrovirus to ferry into adult cells the same four genes they had previously employed to reprogram mouse cells: OCT3/4, SOX2, KLF4, and c-MYC. They reprogrammed cells taken from the facial skin of a 36-year-old woman and from the connective tissue of a 69-year-old man. Roughly one iPC cell line was produced for every 5000 cells they treated with the technique, an efficiency that enabled them to produce several cell lines from each experiment.

Thomson says he and his colleagues already had their own list of 14 candidate reprogramming genes when Yamanaka's mouse results were published. They, like Yamanaka's group, gradually whittled down the list through a systematic process of elimination. Thomson's experiments led to four factors as well: OCT3 and SOX2, as Yamanaka used, and two different genes, NANOG and LIN28. NANOG is another gene associated with ES cells, and LIN28 is a factor that seems to be involved in processing messenger RNA.

Instead of cells from adults, Thomson and his team reprogrammed cells from fetal skin and from the foreskin of a newborn boy. But Thomson says they are working on experiments with older cells, which so far look promising. Their experiments reprogrammed about one in 10,000 cells. The efficiency is less than that of Yamanaka's technique, Thomson says, but is still enough to create several cell lines from a single experiment.

Comparing the two techniques might help scientists learn how the inserted genes work to turn back the developmental clock, Yamanaka says. He says his team tried using NANOG but saw no effect, and LIN28 was not in their initial screen. Thomson says his team tried Yamanaka's four genes without success, but that they may have tried the wrong relative doses.

The fact that Thomson's suite doesn't include a known cancer-causing gene is a bonus, says Wilmut. (The c-MYC Yamanaka used is an oncogene.) But both techniques still result in induced cells that carry multiple copies of the retroviruses used to insert the genes. Those could easily lead to mutations that might cause tumors in tissues grown from the cells. The crucial next step, everyone agrees, is to find a way to reprogram cells by switching on the genes rather than inserting new copies. "It's almost inconceivable at the pace this science is moving that we won't find a way to do this without oncogenes or retroviruses," says stem cell researcher Douglas Melton of Harvard University. "It is not hard to imagine a time when you could add small molecules that would tickle the same networks as these genes" and produce reprogrammed cells without genetic alterations, he says.

Although the cells "act just like human ES cells," Thomson says, there are some differences between the cell types. Yamanaka's group reports that overall human iPC gene expression is very similar, but not identical, to human ES cell gene expression. "It will be probably a few years before we really understand these cells as well as we understand ES cells," Thomson says. But "for drug screening, they're already terribly useful. IVF embryos are very skewed ethnically," he says. But with the new iPC technique, "you can isolate cell lines that represent the genetic diversity of the United States. And I think it will be very straightforward to do."
 

Obviously personhood depends on having particular properties, and you think the conceptus lacks them. But I'm still not sure what you think those properties are, other than the property of being mourned at a funeral.

I think, given the nature of this argument, that the burden is on you to show that zygotes (or any other stage) DO have the traits of persons. You're the one whose original argument relied on that similarity.

But maternal signals aren't where the conceptus gets the information about how to build a brain.

No, this is wrong. The "information" required includes information about when to begin and end certain building processes. Some of that information comes from the womb, not the zygote. Because timing is so critical to development, it's not possible to separate "information" from "timing" as you're trying to do.

Fertilization uncontroversially transforms sperm and egg cells into a different substance.

I don't understand what you mean here. Sperm and egg cells are both human, both have human DNA. That seems to me what you have been treating as "same substance" in previous posts.
 

chris:

An neuron-less ET who behaved like a human adult would still be a person, for instance.

And pigs with wings would be an aviation hazard.

We shoot deer for food despite their billions of neurones, and their sentience.

We don't prosecute people for "murdering" apes, despite their language capacities.

What this has to do with blastocysts, though, which are far from any identifiable human "behav[iour]", is beyond me.

Cheers,
 

chris:

But maternal signals aren't where the conceptus gets the information about how to build a brain. That's what the conceptus does on its own, with no substance-transforming intervention from the outside.

Let's hope the Human Genome Project disks don't crash; destruction of that information would be murder if done intentionally or negligently....

Cheers,
 

Bart writes:

If Induced Pluripotent Stem Cell research pans out, embryonic stem cell research should be halted.

This is science, not law. If IPS does result in what appear to be viable stem cell populations, embryonic research will still be needed, if only for verification and comparison purposes. Just dropping ESC research would be scientifically reckless.

Continuing:
However, embryonic stem cells have failed to provide actual therapies and are unlikely to do so in the foreseeable future because scientists have been unable to program them to become a single cell type and to keep the recipient body's immune system from killing them.

That's why there is a need for continued embryonic stem cell research. The hurdles adult stem cells and the induced skin cells are the same as those facing embryonic stem cells, tumorigenesis among those hurdles.

Since the method for inducing the skin and connective cells also induces tumors under certain conditions, its exciting, but much much farther from ESC's from being viable.
 

This comment has been removed by the author.
 

(Reposted to correct misspelling of Korobkin--sorry about that!)

Mark: "[G]iven the nature of this argument, that the burden is on you to show that zygotes (or any other stage) DO have the traits of persons. You're the one whose original argument relied on that similarity."

Let me review the bidding. Korobkin first made an argument about consciousness and self-awareness; my reply is to point to the reversibly comatose. Second, Korobkin argued from the dependence of the need of the conceptus for assistance from the mother; my reply was that such assistance doesn't turn the conceptus into a different substance. Third, Korobkin argued that on the conceptus-is-a-person view, the ovum and sperm cell are also persons; I replied that the transformation of the sperm cell and ovum into the conceptus turns these two substances into one new one.

Now, independent of that, I proferred what I take to be a sufficient criterion of personhood: possession of the epigenic primordium of a functioning human brain. You replied with incredulity, adding a fourth argument against personhood of the conceptus based on our lack of funerals; I replied that we have reasons for lack of specific grief, independent of the lack of personhood for the conceptus.

Now, this discussion about traits has been in response to your argument about the lack of funerals. So I think the burden's on you to defend the moral significance of funerals, or otherwise say what you're trying to get at.

More broadly, I'm responding to Korobkin's argument that there aren't any significant moral concerns with embryo-destructive research. Unless we're convinced of the non-personhood of the conceptus, that wouldn't be right.

Mark: "The 'information' required includes information about when to begin and end certain building processes. Some of that information comes from the womb, not the zygote. Because timing is so critical to development, it's not possible to separate 'information' from 'timing' as you're trying to do."

Again, my argument is that the inputs from the mother are not sufficiently significant to transform the conceptus into a different entity. They do not amount to giving the conceptus a entirely new capacity, but instead only allow the conceptus to use the information that is already embedded in the conceptus's DNA. The distinctively human functioning of the brain is explained by the fact that the DNA of the conceptus is the way it is, not by the fact that the maternal hormonal levels are what they are.

Me: "Fertilization uncontroversially transforms sperm and egg cells into a different substance."

Mark: "Sperm and egg cells are both human, both have human DNA."

But their fusion produces a new substance--a new entity, a new being.

Arne: "What [discussion of the moral significance of neurons] has to do with blastocysts, though, which are far from any identifiable human 'behav[iour]', is beyond me."

I'm replying to Englightened Layperson's suggestion that the "full neuronal development" of the reversibly comatose is what suffices to establish their personhood.

Me: "[M]aternal signals aren't where the conceptus gets the information about how to build a brain."

Arne: "Let's hope the Human Genome Project disks don't crash; destruction of that information would be murder if done intentionally or negligently...."

Not murder if negligent. But my argument isn't that destroying information about how to build a brain is wrong; my argument is that destroying a being with the epigenetic primordium of a functioning human brain is wrong. The fact that the information about building a brain is internal to the conceptus is part of showing that the conceptus has the epigenetic primordium of a functioning human brain.
 

my reply is to point to the reversibly comatose

This is why I maintain the burden is on you. You used a person as an example in order to argue against the initial post. In order for your example to be meaningful, you need to show how persons and zygotes are similar. So far, you haven't done that, except in ways in which they are also similar to, for example, frogs.

Again, my argument is that the inputs from the mother are not sufficiently significant to transform the conceptus into a different entity. They do not amount to giving the conceptus a entirely new capacity, but instead only allow the conceptus to use the information that is already embedded in the conceptus's DNA. The distinctively human functioning of the brain is explained by the fact that the DNA of the conceptus is the way it is, not by the fact that the maternal hormonal levels are what they are.

This, again, is just wrong. You can't separate heredity, development, and environment the way you're trying to do. It makes no biological sense.

Let's take height as an example. It's meaningless to talk about a person's "capacity" for height in the abstract. Height is a function of (at least) two factors, namely heredity and environment. You cannot separate them; it's meaningless.

Similarly, the womb environment sends signals to the developing, fertilized egg which tell it what to do and when to do it. If you were to put identical eggs into different wombs, you would NOT get identical people. Their size, personality, even sexual identity might very well differ.

But their fusion produces a new substance--a new entity, a new being.

Again, I don't understand what you mean by "substance". "Beings" are not substances. They are made of substances. The "substance" of any person is what we call human. That's also true of any cell within the person, from fingernails to germ cells. They are all the same "substance".
 

Mark: "You used a person as an example in order to argue against the initial post. In order for your example to be meaningful, you need to show how persons and zygotes are similar. So far, you haven't done that, except in ways in which they are also similar to, for example, frogs."

I'm replying to Korobkin's particular argument against the personhood of the conceptus. His argument depends on the false premise that consciousness is required for personhood. I don't need to say anything at all about the conceptus to criticize that premise.

That said, I have repeatedly referred to a property possessed by both the conceptus and an adult, but not possessed by frogs: the property of possessing the epigenetic primordium of a functioning human brain.

Mark: "You can't separate heredity, development, and environment the way you're trying to do. It makes no biological sense."

I'm not sure what position you're defending now. Above, I thought you agreed that air and water do not turn adults into new entities, so the mere fact that a factor is required for deveopment, and may have a huge influence on a being's properties, doesn't mean that the presence of that factor produces a new entity. If you're contending that the mother's contributions are sufficiently significant to turn the conceptus into a new entity, we'd have to look a lot more closely at the embryology to tell what you're claiming. If not, then you agree with my initial response to Korobkin's emphasis on the dependence of the conceptus.

Mark: "If you were to put identical eggs into different wombs, you would NOT get identical people. Their size, personality, even sexual identity might very well differ."

I agree that different wombs will produce people with very different properties. But differences in size and personality and sexual identity are accidental, not essential, because even adults can change them without becoming different entities. The mere fact that hormonal levels and other processes of the mother can affect these sorts of properties does not entail that these processes change the conceptus into a new entity.

Mark: "Again, I don't understand what you mean by 'substance'. 'Beings' are not substances. They are made of substances. The 'substance' of any person is what we call human. That's also true of any cell within the person, from fingernails to germ cells. They are all the same 'substance'."

Sorry if that was unclear--I mean to use "substance" and "entity" and "being" interchangeably. (See definition 1 here; you seem to prefer definition 2, although I don't think a mere part of a human being is of the same kind as the entire human being himself.) To make it clear, just replace "substance" with "entity." Neither the unfertilized ovum nor the sperm is the same entity as the resulting zygote.
 

Neither the unfertilized ovum nor the sperm is the same entity as the resulting zygote.

# posted by Chris : 4:19 PM

Nor is the resulting zykote the same entity as a living, breathing, human. There is no reason to treat it as such.
 

" In order for your example to be meaningful, you need to show how persons and zygotes are similar. So far, you haven't done that, except in ways in which they are also similar to, for example, frogs.

And indeed, according to the literature, at least some frogs have the potential to become people [1].

1. J. Grimm and W. Grimm, Kinder- und Hausmärchen (Berlin, 1812).

-Dan S.
 

chris:

my argument is that destroying a being with the epigenetic primordium of a functioning human brain is wrong....

Pardon my ignerrence, but in my graduate school research in developmental neurobiology, I guess I just missed that section on "epigenetic primordi[a] of a functioning human brain". Could you please explain in greater detain this concept? How does this concept help us? Maybe you could contrast with my thesis on the ethics of extirpation of teratomas here, keeping in mind that these new techniques sometimes produce teratomas (see Science excerpt above).

Cheers,
 

Arne: "Could you please explain in greater detain this concept [of an epigenetic primordium]?"

For some more explanation, see the George and Gomez-Lobo's 2002 statement. The basic idea is that the conceptus can build itself a brain without being changed into a different entity. Tumors can't do that.

On the inference from embryonic personhood to the personhood of skin cells, I take it that the process of cloning skin cells to produce an embryo would cause a substantial change in them--that is, it would produce a new entity.
 

I was LIVID when Bush tried to take Credit for this recent Good News on Stem Cell Scientific Research!! As he Rightly + Morally + Holier-than-Thou in his God-given Pompous Audacity pointed out in his 2 VETOES of EMBRYONIC Stem Cell Research!

These are Cells that are currently just being tossed in the Garbage fer chrissakes!! There's People DYING + Suffering from Every Disease known to ALL MANKIND!!

Not just the One's created in the Image of MonkeyBrain Bush's god*

Personally i could give a Rat's Ass where the CURE comes from - yer not Killing Live Babies with this Important Research!

& by Bush VETOing + putting Roadblocks up every Fucking Step o the way is beyond all Belief!!!

Thank god there are Enlightened Human Beings + Scientists in Israel + Canada + South Korea + China + even America who are Boldly Pursuing this Promising Embryonic Stem Research*

Great Strides have been made in the past 10 Years (a Time Frame even Bush's Brainwashed Flock of Evangelical Fundamentalist Not Very Intelligent Designers should be able to grasp) - But which $25,000 or $100,000 Grant will lead to CURES needs to be given NOW! Not after that Idiot has been in Office 8 Long Years!

If U know of 1 Friend, Acquaintance or Family Member suffering from Parkinson's, Alzheimers, Diabetes, Cancer, or Heart & Stroke Disease then VOTE for Anybody not aligned with Bush in 2008!!

Peace*
 

"Actually, there's no stem cells of any kind have have been approved as "actual therapies"."

Arne, doesn't mean none have been proven to work. The FDA can be rather political about what they approve as demonstrated by the way they fought folic acid supplementation to prevent spinal bifida, long after the science was in.

In fact, a neighbor had his life saved by adult stem cell therapy. The doctor that did it has since, or so I understand, moved to Asia where he can save lives without the FDA harassing him.
 

Chris:

[Arne]: "Could you please explain in greater detain this concept [of an epigenetic primordium]?"

For some more explanation, see the George and Gomez-Lobo's 2002 statement....

I just want to know about WTF it means from a scientific perspective. Perhaps if you left out some visceral (so to speak) idea of "ensoulment", it might have some patina of scientific relevance.

Then there's this stoopidity from the linked article: "Unlike the spermatozoa and the oocytes, it is not a part of the mother or of the father." Nonsense, of course. The spermatozoa and oocytes are not "part of the mother or of the father" either. See Michael Palin's explication below.

... The basic idea is that the conceptus can build itself a brain without being changed into a different entity. Tumors can't do that.

Huh? Haven't seen many "conceptuses" (or "concepti") running around with brains. As I said above, I've seen deer with brains, and chimps with brains, but "conceptuses"? No. Not even "running". Haven't seen too many aliens either; where'd you find them? I'm actually a bit serious on this last one; you seem to be of the opinion that an "alien" would also be a "person" despite not having the same (or similar) "epigenetic primordium" (Chris: "An neuron-less ET who behaved like a human adult would still be a person, for instance."). You still haven't answered my comments on your diversion into "behaviour" as a distinguishing characteristic for nominal "personhood".

Maybe you are saying that these "conceptuses" might, under the right circumstances and surroundings, develop into something else that has a brain. Then I'd be glad to walk down to the beach here, and sell you the "epigenetic primordium" for a new sooper-dooper computer ... cheap but oh, such a bargain.

On the inference from embryonic personhood to the personhood of skin cells, I take it that the process of cloning skin cells to produce an embryo would cause a substantial change in them--that is, it would produce a new entity.

Huh? How is it different? How is it a "new entity"? It still has the "epigenetic primordium" for "personhood", doesn't it? It has the same "information" as did the original zygote (plus or minus a few base pairs). They even made clones. So how do you "differentiate" [so to speak ;-)] in any meaningful way the nucleus of a skin cell from the 16 cell blastocyst? Particularly, compared to actual developed organisms that have brains, that have sentience, that have even such things as "loyalty", "loneliness", even language, and that we kill and sometimes eat?!?!?

Hate to say it, but you're making a distinction that is being shown by science more and more every day to be of no real consequence.

To paraphrase Michael Palin:

"Because ... Every nucleus is sacred.
Every nucleus is great.
If a nucleus is wasted,
God gets quite irate...."

Cheers,
 

God?

Who's God? Yer God??

god is Not Great: How Religion Poisons Everything by Christopher Hitchens

www.WorldCantWait.org
 

brett:

[Arne]: "Actually, there's no stem cells of any kind have have been approved as "actual therapies"."

Arne, doesn't mean none have been proven to work.

Results (in animals and man) have been mixed. But I was careful about what I stated. I was responding to the eedjit cut'n'paste artiste "Bart", who said this: "As a result, adult stem cells are being successfully used in a growing range of medical therapies." (he used "actual therapies" above that in his post WRT ESCs). He was trying to argue that ASCs work and are being used, while ESCs don't. That's just flat-out false. I still want to know where he's getting his agitprop from; he's too uninformed and unedjoomakated to be using all those big words all by himself....

Cheers,
 

Arne: "Perhaps if you left out some visceral (so to speak) idea of 'ensoulment', it might have some patina of scientific relevance."

Not sure what you mean. George and Gomez-Lobo don't use the term, and neither do I.

Arne: "You still haven't answered my comments on your diversion into 'behaviour' as a distinguishing characteristic for nominal 'personhood'."

Do you mean your 2:03 above? That was a bit too short and cryptic for me to make much sense of it. My 3:20 above explained why I was talking about aliens--to defend the claim that neurons, as such, aren't decisive of the moral status of an entity. I was responding to Enlightened Layperson's 10:54.

I'm using "conceptus" as an accommodation to Mark, who didn't like "embryo"--see my 1:36 above.

Arne: "Huh? How is it different? How is it a 'new entity'?"

We're talking about the process of turning a skin cell into an embryo (which hasn't happened yet). My claim is that the sort of radical intervention required to supply the cell with the ability to grow a brain would turn it into a new entity. An essential trait of a normal skin cell is the lack of such an ability. This is a metaphysical claim, not strictly a biological one--of course, since no one has actually produced a human being from a skin cell yet, the biology itself is necessarily somewhat hypothetical.

Remember that all of this is basically a response to the problem of explaining the personhood of the reversibly comatose. We have to point to some property that distinguishes beings properly related to future behaviors like thinking and language from beings that aren't properly related. I think the ability to produce a functioning brain in the future without becoming a new entity is a sufficient criterion, though not a necessary one.
 

Hadn't realized it, but George has a new book coming out next month giving a much more extensive defense of the moral status of the human embryo.

In other news, Rick Garnett calls the discussion here "feisty."
 

Chris:

Arne: "Perhaps if you left out some visceral (so to speak) idea of 'ensoulment', it might have some patina of scientific relevance."

Not sure what you mean. George and Gomez-Lobo don't use the term, and neither do I.

You use the concept. It wedges its way into your little "conceptions". It's "majick" when that little zygote forms, despite the fact that you've done nothing more that mix a batch of chemicals; added the vinegar to the baking soda and now you have a wondrous new entity, the "volcano". Neither the vinegar nor the baking soda have this "epigenetic primordiality"; this capacity to produce a "volcano", but together, voila!, there it is ... unless we do this in an atmosphere of lithium aluminum hydride, or under 27 atmospheres, or on a flat surface or....

You reach the "results" and the "nomenclature" based not on science, but on a predetermined view of what you would like to achieve. Science really doesn't have any concept of "epigenetic primordia". Really.

Arne: "You still haven't answered my comments on your diversion into 'behaviour' as a distinguishing characteristic for nominal 'personhood'."

Do you mean your 2:03 above? That was a bit too short and cryptic for me to make much sense of it. My 3:20 above explained why I was talking about aliens--to defend the claim that neurons, as such, aren't decisive of the moral status of an entity.....

Well and fine. Then the capacity to develop (under appropriate conditions) into neural tissue is then no long a sine qua non of "personhood" either. Let's talk about "behavioural" classifications of "personhood" then, if you want to take this tack instead of your "promordial epigenesis": What "human" behaviour does the 16 cell blastocyst have?

.. I was responding to Enlightened Layperson's 10:54.

Well and fine. Are you arguing different (and apparently contradictory) arguments with different fellow correspondents here?

I'm using "conceptus" as an accommodation to Mark, who didn't like "embryo"--see my 1:36 above.

I don't care what you call it.

Arne: "Huh? How is it different? How is it a 'new entity'?"

We're talking about the process of turning a skin cell into an embryo (which hasn't happened yet)....

And I'm talking about the process of turning a blastocyst into an embryo ... what hasn't happened yet.

... My claim is that the sort of radical intervention required to supply the cell with the ability to grow a brain would turn it into a new entity....

How so? A viral infection is a "radical intervention"? From an informational science standpoint, certainly far less than adding a half-complement of chromosomes.

... An essential trait of a normal skin cell is the lack of such an ability....

Ohhhhhhh ... but it has an "epigenetic primordiality" to do so. Then there's those teratomas (they occur naturally too, you know).

... This is a metaphysical claim, not strictly a biological one--of course, ...

If I was generous, I'd agree. I don't think much of "metaphysics" even. We've gone a long way past that in scientific thinking in the last two millennia.

... since no one has actually produced a human being from a skin cell yet, the biology itself is necessarily somewhat hypothetical.

But they have produced animal clones. Do you think there's something unique to humans that makes such impossible?

Remember that all of this is basically a response to the problem of explaining the personhood of the reversibly comatose....

My comments haven't been directed at that.

... We have to point to some property that distinguishes beings properly related to future behaviors like thinking and language from beings that aren't properly related....

Why? To reach the "results" you want?

... I think the ability to produce a functioning brain in the future without becoming a new entity is a sufficient criterion, though not a necessary one.

WTF is this "new entity" crapola? Or "ability", for that matter. Does "2" have the "ability" to become "3" for sufficiently large values of "2" (or suitably "modified" or "nurtured" "2s")?

Certainly not science.

Cheers,
 

Arne: "You use the concept [of ensoulment]."

I don't understand what could possibly make you think so.

Arne: "Science really doesn't have any concept of 'epigenetic primordia'. Really."

Right. Because it involves the issue of when an entity survives and when it is transformed into a new one, it's a part of metaphysics, not science.

Arne: "[T]he capacity to develop (under appropriate conditions) into neural tissue is then no long a sine qua non of 'personhood' either."

I didn't claim that the ability to build a functioning brain without transformation into a new entity is necessary for personhood, only that it is sufficient.

Arne: "Are you arguing different (and apparently contradictory) arguments with different fellow correspondents here?"

I have no idea what two arguments of mine you think are contradictory. I offered a counterexample involving the reversibly comatose, Enlightened Layperson objected that the reversibly comatose have neurons, I replied that neurons aren't morally decisive, you interjected with some brief and cryptic remarks asking why I was talking about neurons, and I explained the context of my remarks about neurons. Then, later, you complained that I hadn't responded to your argument, and I explained the context again. I'm happy to try to explain how what I'm saying fits together, but I don't have enough to go on about what's puzzling you.

Arne: "A viral infection is a 'radical intervention'?"

I don't understand. Viral infections don't give people the power to reproduce parthenogenetically, and they don't turn skin cells into embryos. If they did, they'd be pretty radical.

Arne: "[T]hey have produced animal clones. Do you think there's something unique to humans that makes such impossible?"

No. But I think cloning that would turn a skin cell into an embryo would produce a substantial change--that is, a new entity.

Me: "An essential trait of a normal skin cell is the lack of such an ability [to grow a brain]."

Arne: "Ohhhhhhh ... but it has an 'epigenetic primordiality' to do so."

No, I claim that the normal skin cell and the embryo are different. The embryo can grow a brain--that is, it has the epigenetic primordium of one--but the normal skin cell can't--that is, it lacks such an epigenetic primordium.

Arne: "I don't think much of 'metaphysics' even. We've gone a long way past that in scientific thinking in the last two millennia."

I'd disagree, obviously. If you reject the entire notion of discussing an entity's essential and accidental properties or the conditions under which an entity can survive, I'm not sure there's much I can do to help you out. I think the death of metaphysics has been prematurely declared a few times, though.

Me: "... We have to point to some property that distinguishes beings properly related to future behaviors like thinking and language from beings that aren't properly related....

Arne: "Why? To reach the 'results' you want?"

No, to reach the result everyone wants: to explain why the reversibly comatose, who aren't doing anything characteristic of persons now, are still persons. Korobkin's original argument uses a criterion of personhood that would exclude them.

Arne: "WTF is this 'new entity' crapola? ... Certainly not science."

Right. It's metaphysics. Biological facts don't answer, all by themselves, when entities survive and when they don't.
 

Chris:

[Arne]: "You use the concept [of ensoulment]."

I don't understand what could possibly make you think so.

Your terminology and your arguments. Not to mention your links.

[Arne]: "Science really doesn't have any concept of 'epigenetic primordia'. Really."

Right. Because it involves the issue of when an entity survives and when it is transformed into a new one, it's a part of metaphysics, not science.

And things fall to the floor because that's their "proper place". Just ask my buttered toast.

But at least you acknowledge that it is not science.

[Arne]: "[T]he capacity to develop (under appropriate conditions) into neural tissue is then no long a sine qua non of 'personhood' either."

I didn't claim that the ability to build a functioning brain without transformation into a new entity is necessary for personhood, only that it is sufficient.

Why? But FWIW, I assume you're then militantly vegetarian?

[Arne]: "Are you arguing different (and apparently contradictory) arguments with different fellow correspondents here?"

I have no idea what two arguments of mine you think are contradictory. I offered a counterexample involving the reversibly comatose, Enlightened Layperson objected that the reversibly comatose have neurons, I replied that neurons aren't morally decisive, you interjected with some brief and cryptic remarks asking why I was talking about neurons, and I explained the context of my remarks about neurons. Then, later, you complained that I hadn't responded to your argument, and I explained the context again. I'm happy to try to explain how what I'm saying fits together, but I don't have enough to go on about what's puzzling you.

Oh, I get it. Everything's a "person" that you say should be a person. Aiens, blastocysts, maybe even computers. Gotcha. Still trying to figure out how a skin cell that has the "epigenetic primordium" to become an organism with a functioning brain is not.

[Arne]: "A viral infection is a 'radical intervention'?"

I don't understand. Viral infections don't give people the power to reproduce parthenogenetically, and they don't turn skin cells into embryos. If they did, they'd be pretty radical.

You didn't read the papers, didja? ;-)

Maybe you ought to read up on what's being done to see if it changes your mind any on what things have "epigenetic primordia".

[Arne]: "[T]hey have produced animal clones. Do you think there's something unique to humans that makes such impossible?"

No. But I think cloning that would turn a skin cell into an embryo would produce a substantial change--that is, a new entity.

How so? Because you say it's a "new entity"? But can't we, with just as much faith and credit, assert that the foetus is a "new entity" from the blastocyst? I certainly looks different, acts different, probably even tastes different.

[Chris]: "An essential trait of a normal skin cell is the lack of such an ability [to grow a brain]."

[Arne]: "Ohhhhhhh ... but it has an 'epigenetic primordiality' to do so."

No, I claim that the normal skin cell and the embryo are different. The embryo can grow a brain--that is, it has the epigenetic primordium of one--but the normal skin cell can't--that is, it lacks such an epigenetic primordium.

Nd on what basis do you say that? How do you reconcile that with the fact that they produced clones from skin cells? (Clarification, BTW, the clones so far have produced the three major types of tissue, including mesoderm, endoderm, and ectoderm, and have differentieated into nerve cells, but a complete viable cloned organism [in rhesus monkeys at least] has yet to be accomplished).

[Arne]: "I don't think much of 'metaphysics' even. We've gone a long way past that in scientific thinking in the last two millennia."

I'd disagree, obviously. If you reject the entire notion of discussing an entity's essential and accidental properties or the conditions under which an entity can survive, I'm not sure there's much I can do to help you out. I think the death of metaphysics has been prematurely declared a few times, though.

Damn. That bread fell again.

[Chris]: "... We have to point to some property that distinguishes beings properly related to future behaviors like thinking and language from beings that aren't properly related....

[Arne]: "Why? To reach the 'results' you want?"

No, to reach the result everyone wants: to explain why the reversibly comatose, who aren't doing anything characteristic of persons now, are still persons. Korobkin's original argument uses a criterion of personhood that would exclude them.

I don't think it's necessary to "tweak" these criteria so far as to include blastocysts so as to cover the ethical issues of comatose people. In fact, the issues of PVS/comatose people is still in flux; which is why the extension to cell clumps of 16 cells that have none of even the distinct features of comatose people (outside of their genetic makeup and essential metabolic pathways) is so extreme.

[Arne]: "WTF is this 'new entity' crapola? ... Certainly not science."

Right. It's metaphysics. Biological facts don't answer, all by themselves, when entities survive and when they don't.

IOW, you're making up this classification of "new entity" ad hoc, to suit your purposes. No thanks. I don't find it a useful concept either scientifically or ethically.

Cheers,
 

P.S., Chris:

If you want to continue this, why don't we take it somewhere else? My blog is available, but if you'd prefer somewhere else, feel free.

Cheers,
 

Arne: "If you want to continue this, why don't we take it somewhere else?"

Just a few more clarifications from your last post.

Arne: "Your terminology and your arguments [make me think you use the concept of ensoulment]. Not to mention your links."

I never used the term, and never did George and Gomez-Lobo. You brought it in from nowhere.

Me: "[T]he ability to build a functioning brain without transformation into a new entity is [sufficient for personhood]."

Arne: "I assume you're then militantly vegetarian?"

Should've said functioning human brain.

Me: "I think cloning that would turn a skin cell into an embryo would produce a substantial change--that is, a new entity."

Arne: "How so? Because you say it's a 'new entity'? But can't we, with just as much faith and credit, assert that the foetus is a 'new entity' from the blastocyst? I certainly looks different, acts different, probably even tastes different."

No. I think the difference is the amount of external intervention into the operating structures of a cell is critical. Nothing intervenes from outside to change the structure of the embryo in order to change it into a fetus, child, and adult. But cloning involves radical intervention into the internal structure of a cell.

Arne: "I don't think it's necessary to 'tweak' these criteria so far as to include blastocysts so as to cover the ethical issues of comatose people."

I'm not trying to address the actual ethical dilemmas involving comatose people; I'm proposing comatose people as a counterexample, and saying we obviously have to adjust our criteria if they exclude the comatose from personhood. You haven't either (a) explained how a comatose person could satisfy a Tooley-Warren-style immediate-exercise criterion for personhood, or (b) offered a plausible alternative criterion for personhood that would include the comatose but exclude the embryo.
 

Chris:

[Chris]: "[T]he ability to build a functioning brain without transformation into a new entity is [sufficient for personhood]."

[Arne]: "I assume you're then militantly vegetarian?"

Should've said functioning human brain.

Ummm. And assume your conclusion? Why, how handy....

[Chris]: "I think cloning that would turn a skin cell into an embryo would produce a substantial change--that is, a new entity."

[Arne]: "How so? Because you say it's a 'new entity'? But can't we, with just as much faith and credit, assert that the foetus is a 'new entity' from the blastocyst? I certainly looks different, acts different, probably even tastes different."

No. I think the difference is the amount of external intervention into the operating structures of a cell is critical....

Huh? Why? It's just a matter of "environment", you know, STP, no toxins, an endometrium here, a virus there.... You won't get a foetus without an endometrium.

If the measure is how far it can go without "external intervention", then wouldn't at least some very significant dividing line be reasonably set at implantation? (not that I accept this "measure" as being a compellingly valid distinction).

... Nothing intervenes from outside to change the structure of the embryo in order to change it into a fetus, child, and adult....

Blastocyst. "Blastocysts in Space: The Alien Goo Invasion!!!!" Think that works?

... But cloning involves radical intervention into the internal structure of a cell.

How so? Please do tell. If you read the reports (did you?), it's 'just a viral infection' ... you know, kind of like getting a cold (or HPV). So do people lose their "personhood" by becoming "new entities" then?

[Arne]: "I don't think it's necessary to 'tweak' these criteria so far as to include blastocysts so as to cover the ethical issues of comatose people."

I'm not trying to address the actual ethical dilemmas involving comatose people; I'm proposing comatose people as a counterexample, and saying we obviously have to adjust our criteria if they exclude the comatose from personhood. You haven't either (a) explained how a comatose person could satisfy a Tooley-Warren-style immediate-exercise criterion for personhood, or (b) offered a plausible alternative criterion for personhood that would include the comatose but exclude the embryo.

And? I'm not the one claiming that it is impermissible to use blastocysts to produce ESCs....

But, as you can see from my blog, I am vehemently opposed to "teratoma/preborn-monstrosity-murder" ... even if the health of the mother is involved. ;-)

Cheers,