Robert P. George Embryo ethics - Stand to Reason …research or therapy if they could be ob-tained from non-embryonic sources, or if they could be acquired by using em-bryos lost in

If we were to contemplate killing men-tally handicapped infants to obtaintransplantable organs, no one wouldcharacterize the controversy that woulderupt as a debate about organ transplan-tation. The dispute would be about theethics of killing handicapped children to harvest their vital organs. We couldnot resolve the issue by considering howmany gravely ill people we could save byextracting a heart, two kidneys, a liver,etc., from each mentally handicappedchild. Instead, we would have to answerthis question: is it right to relegate a cer-tain class of human beings–the handi-capped–to the status of objects that canbe killed and dissected to bene½t others?

By the same token, strictly speakingours is not a debate about stem cell re-search. No one would object to the useof pluripotent stem cells in biomedical

research or therapy if they could be ob-tained from non-embryonic sources, orif they could be acquired by using em-bryos lost in miscarriages.1 The point of

Dædalus Winter 2008 23

Robert P. George is McCormick Professor of Ju-risprudence and director of the James MadisonProgram in American Ideals and Institutions atPrinceton University. He is coauthor of “Body-Self Dualism in Contemporary Ethics and Poli-tics” (2008) and “Embryo: The Case for HumanLife” (2008). He is a member of the President’sCouncil on Bioethics and formerly served on theUnited States Commission on Civil Rights.

© 2008 by the American Academy of Arts & Sciences

Robert P. George

Embryo ethics

1 It appears that we will soon be able to ob-tain embryonic stem cells, or their equivalent,by means that do not require the destruction of human embryos. Important successes in producing pluripotent stem cell lines by repro-gramming (or ‘de-differentiating’) human so-matic cells have been reported in highly publi-cized papers by James A. Thomson’s researchgroup, “Induced Pluripotent Stem Cell LinesDerived from Human Somatic Cells,” Sciencex-press, www.sciencexpress.org/22 November2007/ 10.1126science.1151526, and Shinya Ya-manaka’ s research group, “Induction of Pluri-potent Stem Cells from Adult Fibroblasts byDe½ned Factors,” Cell (published online, No-vember 20, 2007). Citing these successes, IanWilmut of Edinburgh University, who is credit-ed with producing Dolly the sheep by cloning,has decided not to pursue a license granted byBritish authorities to attempt to produce clonedhuman embryos for use in biomedical research.According to Wilmut, embryo-destructivemeans of producing the desired stem cells willbe unnecessary: “The odds are that by the timewe make nuclear transfer [cloning] work in hu-mans, direct reprogramming will work too. Iam anticipating that before too long we will beable to use the Yamanaka approach to achievethe same, without making human embryos.”Wilmut is quoted in Roger High½eld, “DollyCreator Ian Wilmut Shuns Cloning,” Telegraph.co.uk, November 16, 2007. For a survey of possi-ble non-embryo-destructive methods of obtain-

24 Dædalus Winter 2008

Robert P.George onlife

controversy is the ethics of deliberatelydestroying human embryos to producestem cells. The threshold question iswhether it is right to kill members of acertain class of humans–those in theembryonic stage of development–tobene½t others.

Supporters of embryo-destructive re-search insist, however, that human em-bryos are not human beings–or if theyare human beings, that they are not yet‘persons.’ It is therefore morally accept-able, they say, to ‘disaggregate’ them for the sake of research aimed at ½ndingcures or treatments for juvenile diabetesand other horrible afflictions.

At the heart of the debate over em-bryo-destructive research, then, are twoquestions: is a human embryo a humanbeing, and, if so, what is owed to an em-bryonic human as a matter of justice?

I will say nothing about religion or the-ology. This is not a tactical decision;rather, it reflects my view about how tothink about the dispute over killing hu-man embryos. It is sometimes said thatopposition to embryo-destructive re-search is based on a controversial theol-ogy of ‘ensoulment.’ But one need notengage questions of whether human be-ings have spiritual souls in consideringwhether human embryos are human be-ings. Nor must one appeal to any theolo-gy of ensoulment to show that there is arational basis for treating all human be-ings–including those at the embryonicstage–as creatures possessing intrinsicworth and dignity.2

We should resolve our national debateover embryo-destructive research on thebasis of the best scienti½c evidence as towhen the life of a new human being be-gins, and the most careful philosophicalreasoning as to what is owed to a humanbeing at any stage of development. Re-ligious conviction can motivate us tostand up and speak out in defense of hu-man life and dignity. And religious peo-ple should never hesitate to do that. Butwe need not rely on religious authorityto tell us whether a human embryo is anew living member of the species Homosapiens or whether all human beings–irrespective of not only race, ethnicity,and sex but also age, size, stage of devel-opment, and condition of dependency–possess full moral worth and dignity.The application of philosophical princi-

ing pluripotent stem cells, see The President’sCouncil on Bioethics, “White Paper: Alterna-tive Sources of Pluripotent Stem Cells,” May2005, available at www.bioethics.gov.

2 It is worth pointing out that contrary to a common misunderstanding, the Catholic

Church does not try to draw scienti½c infer-ences about the humanity or distinctness ofthe human embryo from theological proposi-tions about ensoulment. It works the otherway around. The theological conclusion thatan embryo is ‘ensouled’ would have to bedrawn on the basis of (among other things)scienti½c ½ndings about the self-integration,distinctness, unity, determinateness, etc., ofthe developing embryo. Contrary to anothermisunderstanding, the Catholic Church hasnot declared a teaching on the ensoulment ofthe early embryo. Still, the Church af½rms therational necessity of recognizing and respect-ing the dignity of the human being at all de-velopmental stages, including the embryonicstage, and in all conditions. For a clear state-ment of Catholic teaching and its ground, seethe document Donum Vitae, issued by the Con-gregation for the Doctrine of the Faith on Feb-ruary 22, 1987, http://www.vatican.va/roman_curia/congregations/cfaith/documents/rc_con_cfaith_doc_19870222_respect-for-human-life_en.html: “[T]he conclusions of scienceregarding the human embryo provide a valu-able indication for discerning by the use ofreason a personal presence at the moment of this ½rst appearance of a human life: howcould a human individual not be a human per-son?” (Section 5, I, 1, para. 3)


Embryoethics

ples in light of facts established by mod-ern embryological science is more thansuf½cient for that task.3

The adult human being that is now you or me is the same being who, at anearlier stage, was an adolescent and, be-fore that, a child, an infant, a fetus, andan embryo.4 Even in the embryonicstage, you and I were undeniably wholeliving members of the species Homo sa-piens. We were then, as we are now, dis-tinct and complete–though, in the be-ginning, developmentally immature–human organisms. We were not mereparts of other organisms.

A human embryo is not something dif-ferent in kind from a human being, like a rock, or a potato, or a rhinoceros. Ahuman embryo is a human individual in the earliest stage of his or her natural

development.5 Unless severely damagedor deprived of a suitable environment,an embryonic human being will, by di-recting his or her own integral organicfunctioning, develop himself or herselfto each new stage of developmental ma-turity along the gapless continuum of ahuman life. The embryonic, fetal, infant,child, and adolescent stages are just that:stages in the development of a determi-nate and enduring entity–a human be-ing–who comes into existence as a sin-gle-celled organism (zygote) and grows,if all goes well, into adulthood manyyears later.6

3 My point here is not to make light of, muchless to denigrate, the important witness ofmany religious traditions to the profound, in-herent, and equal dignity of all members of thehuman family. Religious conviction can, andmany traditions do, reinforce ethical proposi-tions that can be rationally af½rmed even apartfrom religious authority.

4 Thus, “recollecting (at her birth) his appre-ciation of Louise Brown [the ½rst ivf baby] asone or two cells in his petri dish, [Robert] Ed-wards [said]: ‘She was beautiful then and she is beautiful now.’” John Finnis, “Some Funda-mental Evils in Generating Human Embryos byCloning,” in Cosimo Marco Mazzoni, ed., Eti-ca della Ricerca Biologia (Florence: Leo Olschki,2000), 116. Edwards and his coauthor, PatrickSteptoe, accurately described the embryo as “amicroscopic human being–one in its very ear-liest stages of development.” Robert Edwardsand Patrick Steptoe, A Matter of Life (London:Hutchinson’s, 1981), 83. The human being inthe embryonic stage of development is “passingthrough a critical period in its life of great ex-ploration: it becomes magni½cently organised,switching on its own biochemistry, increasingin size, and preparing itself quickly for implan-tation in the womb.” Ibid., 97.

5 Keith Moore and T. V. N. Persaud, in The De-veloping Human: Clinically Oriented Embryology,perhaps the most widely used embryology text,make the following unambiguous statementabout the beginning of a new and distinct hu-man individual: “Human development beginsat fertilization when a male gamete or sperm(spermatozoon) unites with a female gamete oroocyte (ovum) to form a single cell–a zygote.This highly specialized, totipotent cell markedthe beginning of each of us as a unique individual.”Keith Moore and T. V. N. Persaud, The Develop-ing Human: Clinically Oriented Embryology (Phil-adelphia: Saunders/Elsevier, 2008), 15 (empha-sis added).

6 A human embryo (like a human being in thefetal, infant, child, or adolescent stage) is not a‘prehuman’ organism with the mere potentialto become a human being. No human embryol-ogy textbook known to me presents, accepts, or remotely contemplates such a view. Instead,leading embryology textbooks assert that a hu-man embryo is–already and not merely poten-tially–a new individual member of the speciesHomo sapiens. His or her potential, assuming asuf½cient measure of good health and a suitableenvironment, is to develop by an internally di-rected process of growth through the furtherstages of maturity on the continuum that is hisor her life. Nor is there any such thing as a ‘pre-embryo.’ That concept was invented, as LeeSilver pointed out in his book Remaking Eden(New York: Avon Books, 1997), 39, for political,and not scienti½c, reasons.



By contrast, the gametes whose unionbrings into existence the embryo are not whole or distinct organisms. Each is functionally (and genetically) identi½-able as part of the male or female (poten-tial) parent. Moreover, each gamete hasonly half the genetic material needed toguide the development of an immaturehuman being toward full maturity. Theyare destined either to combine with anoocyte or spermatozoon and generate anew and distinct organism, or simply todie. When fertilization occurs, they donot survive; rather, their genetic materi-al enters into the composition of a neworganism.

But none of this is true of the humanembryo, from the zygote and blastulastages onward. The combining of thechromosomes of the spermatozoon andof the oocyte generates what humanembryology identi½es as a new, distinct,and enduring organism. Whether pro-duced by fertilization, Somatic Cell Nu-clear Transfer (scnt), or some othercloning technique, the human embryopossesses all of the genetic material andother qualities needed to inform andorganize its growth.7 The direction of itsgrowth is not extrinsically determined,but is in accord with the information

within it.8 Nor does it merely possessorganizational information for matura-tion; it actively uses that information inan internally directed process of devel-opment. The human embryo, then, is awhole and distinct human organism–an embryonic human being.

If the embryo is not a complete organ-ism, what can it be? Unlike the sperma-tozoa and the oocytes, it is not merely apart of a larger organism, namely, themother or the father. Nor is it a disor-dered growth or gamete tumor, such asa complete hydatidiform mole or ter-atoma.

Someone might say that the early em-bryo is an intermediate form, somethingwhich regularly emerges into a wholehuman organism but is not one yet. Butwhat could cause the emergence of thewhole human organism, and cause itwith regularity? As I have already ob-served, from the zygote stage forwardthe development of this organism is di-rected from within, or by the organism it-self. So, after the embryo comes into be-ing, no event or series of events occurthat we could construe as the productionof a new organism–that is, nothing ex-trinsic to the developing organism itselfacts on it to produce a new character or a new direction in development.9

A supporter of embryo-destructiveresearch might concede that a human

7 A cloned human embryo is not a subhumanorganism. Cloning produces a human embryoby combining what is normally fused and ac-tivated in fertilization, that is, a properly epi-genetically disposed human genome and theoocyte cytoplasm. Cloning, like fertilization,generates a new and complete, though imma-ture, human organism. Cloned embryos there-fore ought to be treated as having the samemoral status, whatever that might be, as otherhuman embryos. I respond to the arguments ofmy colleague on the President’s Council on Bio-ethics, Paul McHugh, who claims that clonedembryos are not human beings but “clonotes,”in the latter half of Robert P. George and Pat-rick Lee, “Acorns and Embryos,” New Atlantis 7(2005): 90–100.

8 The ½rst one or two divisions, in the ½rstthirty-six hours, occur largely under the direc-tion of the messenger rna acquired from theoocyte. Still, the embryo’s genes are expressedas early as the two-celled stage and are requiredfor subsequent development to occur normally.See Ronan O’Rahilly and Fabiola Mueller, Hu-man Embryology and Teratology (New York: JohnWiley & Sons, 2000), 38.

9 For a fuller explanation, see Patrick Lee andRobert P. George, “The First Fourteen Days ofHuman Life,” New Atlantis 13 (2006).


Embryoethics

embryo is a human being in a biologi-cal sense, yet deny that we owe humanbeings in the early stages of their devel-opment full moral respect, such that wemay not kill them to bene½t more fullydeveloped human beings who are suffer-ing from afflictions.

But to say that embryonic human be-ings do not deserve full respect, onemust suppose that not every human be-ing deserves full respect. And to do that,one must hold that those human beingswho warrant full respect deserve it notby virtue of the kind of entity they are, but,rather, because of some acquired charac-teristic that some human beings (or hu-man beings at some stages) have andothers do not, and which some humanbeings have in greater degree than oth-ers do.

This position is untenable. One neednot be actually or immediately conscious,reasoning, deliberating, making choices,etc., in order to be a human being whodeserves full moral respect, for plainlywe should accord people who are asleepor in reversible comas such respect. Butif one denied that human beings are valu-able by virtue of what they are, and re-quired an additional attribute, it wouldhave to be a capacity of some sort, and,obviously, a capacity for certain mentalfunctions.

Of course, human beings in the em-bryonic, fetal, and early infant stageslack immediately exercisable capacitiesfor mental functions characteristicallycarried out by most human beings atlater stages of maturity. Still, they pos-sess these very capacities in principe velradice, that is, in radical or ‘root’ form.Precisely by virtue of the kind of entitythey are, they are from the beginningactively developing themselves to thestages at which these capacities will (ifall goes well) be immediately exercis-able. Although, like infants, they have

not yet developed themselves to thestage at which they can perform intel-lectual operations, it is clear that theyare rational animal organisms.10 That isthe kind of entity they are.

Here, it is important to distinguishtwo senses of the ‘capacity’ for mentalfunctions: an immediately exercisablecapacity, and a basic natural capacity,which develops over time. We have good reason to believe that the secondsense, and not the ½rst, provides the ba-sis for regarding human beings as endsin themselves, and not as means only–as subjects possessing dignity and hu-man rights, and not as mere objects.

First, the developing human beingdoes not reach a level of maturity atwhich he or she performs a type of men-tal act that other animals do not perform–even animals such as dogs and cats–until at least several months after birth.A six-week-old baby lacks the immediate-ly exercisable capacity to form abstractconcepts, engage in deliberation, andperform many other characteristically

10 For an entity to have a rational nature is forit to be a certain type of substance; having a ra-tional nature, unlike, say, being tall, or Croatian,or gifted in mathematics, is not an accidentalattribute. Each individual of the human specieshas a rational nature, even if disease or defectblocks its full development and expression insome individuals. If the disease or defect couldsomehow be corrected, it would perfect the in-dividual as the kind of substance he is; it wouldnot transform him into an entity of a differentnature. Having a rational nature is, in Jeff Mc-Mahan’s terms, a “status-conferring intrinsicproperty.” So my argument is not that everymember of the human species should be ac-corded full moral respect based on the fact thatthe more mature members have a status-con-ferring intrinsic property, as McMahan inter-prets the “nature-of-the-kind argument.” Seehis “Our Fellow Creatures,” The Journal of Eth-ics 9 (2005): 355 ff. Rather, my proposition isthat having a rational nature is the basis for fullmoral worth, and every human individual pos-sesses that status-conferring feature.



human mental functions. If we owed fullmoral respect only to those who possessimmediately exercisable capacities forcharacteristically human mental func-tions, it would follow that six-week-oldinfants do not deserve full moral re-spect.11 Therefore, if we may legitimate-ly destroy human embryos to advancebiomedical science, then logically, sub-ject to parental approval, the body partsof human infants should also be fairgame for scienti½c experimentation.12

Second, the difference between thesetwo types of capacity is merely a differ-ence between stages along a continuum.The immediately exercisable capacity for mental functions is only the develop-ment of an underlying potentiality thatthe human being possesses simply byvirtue of the kind of entity it is. The ca-pacities for reasoning, deliberating, andmaking choices are gradually broughttoward maturation, through gestation,childhood, adolescence, and so on. Butthe difference between a being that de-serves full moral respect and a being thatdoes not (and can therefore legitimatelybe killed to bene½t others) cannot con-sist only in the fact that while both havesome feature, one has more of it than the other. A mere quantitative differencecannot by itself provide a justi½cation

for treating entities in radically differentways.13

Third, the acquired qualities proposedas criteria for personhood, such as self-consciousness or rationality, come in an in½nite number of degrees. If humanbeings are worthy of full moral respectonly because of such qualities, and thosequalities come in varying degrees, hu-mans should possess rights in varyingdegrees. The proposition that all humanbeings are created equal would be rele-gated to the status of a myth: since somepeople are more rational than others(that is, have developed that capacity toa greater extent than others have), somepeople would be greater in dignity thanothers, and the rights of the superiorswould trump those of the inferiors.14

So it cannot be the case that some hu-man beings and not others are intrinsi-cally valuable by virtue of a certain de-

11 Clear-headed and unsentimental believersthat full moral respect is due only to thosehuman beings who possess immediately exer-cisable capacities for characteristically humanmental functions do not hesitate to say thatyoung infants do not deserve full moral respect.See, for example, Peter Singer, “Killing Babiesis Not Always Wrong,” The Spectator 16 (Sep-tember 1995): 20–22.

12 Not long ago, Peter Singer was asked wheth-er there would be anything wrong with a socie-ty that bred children for spare parts on a mas-sive scale. “No,” was his reply. See “Blue StatePhilosopher,” World Magazine, November 27,2004.

13 Michael Gazzaniga has suggested that theembryo is to the human being what Home De-pot is to a house, i.e., a collection of uninte-grated components. According to Gazzaniga,“it is a truism that the blastocyst has the po-tential to be a human being. Yet at that stage of development it is simply a clump of cells . . . .An analogy might be what one sees when walk-ing into a Home Depot. There are the parts and potential for at least 30 homes. But if thereis a ½re at Home Depot, the headline isn’t 30homes burn down. It’s Home Depot burnsdown.” Quoted as “Metaphor of the Week” in Science 295 (5560) (March 1, 2002): 1637.Gazzaniga gives away the game, however, inconceding, as he must, that the term ‘blasto-cyst’ refers to a stage of development in the lifeof a determinate, enduring, integrated, and, in-deed, self-integrating entity. If we must drawan analogy to a Home Depot, then it is thegametes (or the materials used in cloning togenerate an embryo), and not the embryo, thatconstitute the “parts and potential.”

14 This conclusion would follow regardless of the acquired quality we chose as qualifyingsome human beings (or human beings at somedevelopmental stages) for full respect.


Embryoethics

gree of development. Rather, all humanbeings are intrinsically valuable (in theway that enables us to ascribe to themequality and basic rights) because of thekind of being they are.

Since human beings are intrinsicallyvaluable and deserve full moral respectby virtue of what they are, it follows thatthey are intrinsically and equally valu-able from the point at which they come intobeing. Even in the embryonic stage of ourlives, each of us was a human being and,as such, worthy of concern and protec-tion. Embryonic human beings, whetherbrought into existence by union of gam-etes, scnt, or other cloning technolo-gies, should be accorded the respect giv-en to human beings in other develop-mental stages.15

I wish to turn now to some argumentsthat advocates of embryo-destructiveresearch have advanced to cast doubt on the proposition that human embryosdeserve to be accorded full moral status.

In defending research involving thedestruction of human embryos, RonaldBailey, a science writer for Reason maga-zine, developed an analogy between em-bryos and somatic cells in light of thepossibility of human cloning.16 Baileyclaims that every cell in the human bodyhas as much potential for developmentas any human embryo. Embryos there-fore have no greater dignity or highermoral status than ordinary somatic cells.Bailey observes that each cell in the hu-

man body possesses the entire dna

code; each has become specialized (asmuscle, skin, etc.) because most of thatcode has been turned off. In cloning,those previously deactivated portions ofthe code are reactivated. So, Bailey says,quoting Australian bioethicist JulianSavulescu, “if all our cells could be per-sons, then we cannot appeal to the factthat an embryo could be a person to jus-tify the special treatment we give it.”Since plainly we are not prepared to re-gard all of our cells as human beings, weshould not regard embryos as human be-ings.

Bailey’s analogy between somatic cellsand human embryos collapses, however,under scrutiny. The somatic cell is some-thing from which (together with extrin-sic causes) a new organism can be gener-ated by the process of somatic cell nucle-ar transfer, or cloning; it is certainly not,however, a distinct organism. A humanembryo, by contrast, already is a dis-tinct, self-developing, complete humanorganism.

Bailey suggests that the somatic celland the embryo are on the same level be-cause both have the ‘potential’ to devel-op to a mature human being. The kind of ‘potentiality’ possessed by somaticcells that might be used in cloning dif-fers profoundly, however, from the po-tentiality of the embryo. A somatic cellhas a potential only in the sense thatsomething can be done to it (or donewith it) so that its constituents (its dna

molecules) enter into a distinct wholehuman organism, which is a human be-ing, a person. In the case of the embryo,by contrast, he or she already is actively–indeed dynamically–developing him-self or herself to the further stages ofmaturity of the distinct organism–thehuman being–he or she already is.

True, the whole genetic code is presentin each somatic cell; and this code can

15 For a more complete presentation of this ar-gument, see Patrick Lee and Robert P. George,“The Wrong of Abortion,” in Andrew I. Cohenand Christopher Wellman, eds., ContemporaryDebates in Applied Ethics (New York: BlackwellPublishers, 2005), 13–26.

16 Ronald Bailey, “Are Stem Cells Babies?”available at http://www.reason.com/rb/rb071101.html.

guide the growth of a new entire organ-ism. But this point does nothing to showthat a somatic cell’s potentiality is thesame as a human embryo’s. When sci-entists remove the nucleus of an ovum,insert the nucleus of a somatic cell intothe remainder of the ovum, and give itan electric stimulus, they are doing morethan merely placing the somatic cell inan environment hospitable to its contin-uing maturation and development. Theyare generating a wholly distinct, self-integrating, entirely new organism–anembryo, in other words. The entity–theembryo–brought into being by this pro-cess is radically different from the con-stituents that entered into its generation.

Somatic cells, in the context of clon-ing, then, are analogous not to embryos,but to the gametes whose union resultsin the generation of an embryo in thecase of ordinary sexual reproduction.You and I were never either a sperm cellor an ovum. Nor would a person whowas brought into being by cloning haveonce been a somatic cell. To destroy anovum or a skin cell whose constituentsmight have been used to generate a newand distinct human organism is not todestroy a new and distinct human organ-ism–for no such organism exists or everexisted. But to destroy a human embryois precisely to destroy a new, distinct,and complete human organism–an em-bryonic human being.17

Michael Gazzaniga, a psychologistand neuroscientist at the University ofCalifornia, Santa Barbara, has proposeda different argument. While agreeingthat a human embryo is an entity pos-sessing a human genome, he has sug-gested that a ‘person’ comes into beingonly with the development of a brain.Prior to that point we have a humanorganism, but one lacking the dignityand rights of a person.18 We may there-fore legitimately treat human beings inthe earliest stages of development as wewould treat organs available for trans-plantation (assuming, as with trans-plantable organs, that proper consent for their use is given, etc.).

In presenting his case, Gazzaniga ob-serves that modern medicine treats thedeath of the brain as the death of theperson–authorizing the harvesting oforgans from the remains of the person,even if some physical systems are stillfunctioning. If a human being is no lon-ger a person with rights once the brainhas died, then surely a human being isnot yet a person prior to the develop-ment of the brain.

This argument suffers, however, froma damning defect. Under prevailing lawand medical practice, the rationale forbrain death is not that a brain-dead body



17 Lee and I replied to Bailey in a series of ex-changes on National Review Online here: 1) (Ourcritique) http://www.nationalreview.com/comment/comment-george072001.shtml; 2)(Bailey’s response) http://www.nationalreview.com/comment/comment-bailey072501.shtml;3) (Our response) http://www.nationalreview.com/comment/comment-george073001.shtml.

We have responded to similar arguments re-cently advanced by Lee Silver in his book Chal-lenging Nature here: 1) (Our critique) http://article.nationalreview.com/?q=otniywm2ZjJ

iywvlN2IyMzFjowywmdzmmtc4MzU2mgu

=; 2) (Silver’s response) http://article.nation-alreview.com/?q=Mjg2Y2Rkndm1Mzlkmgm

yMjI3NjhkYmE0ztrjotgyzde=; 3) (Our re-sponse) http://article.nationalreview.com/?q=MjNmZmYyN2NhNjFkywrhNmExmda2Yzhimdy5YzMyyti=; 4) (Silver’s second re-sponse, followed by our second response)http://article.nationalreview.com/?q=zdk5z

te4MjBimdfmZjc0M2EyNjE0mdc2ZjA4YmRmN2U=.

18 President’s Council on Bioethics, Session 5meeting, January 18, 2002, transcript availableat http://bioethics.gov/transcripts/jan02/jan18session5.html.

is a living human organism but no lon-ger a person. Rather, brain death is ac-cepted because the irreversible collapseof the brain is believed to destroy the ca-pacity for self-directed integral organicfunctioning in human beings who havematured to the stage at which the brainperforms a key role in integrating the or-ganism. In other words, at brain death a unitary organism is believed no longerto exist.19 By contrast, although an em-bryo has not yet developed a brain, it isclearly exercising self-directed integralorganic functioning, and so it is a unitaryorganism. Its capacity to develop a brainis inherent and progressing, just as thecapacity of an infant to develop its brainsuf½ciently for it actually to think is alsointrinsic and unfolding.

Unlike a corpse–the remains of whatwas once a human organism but is nowdead, even if particular systems may bearti½cially sustained–a human organ-ism in the embryonic stage of develop-ment is a complete, uni½ed, self-inte-grating human individual. It is not deadbut very much alive, even though itsself-integration and organic functioningare not brain-directed at this stage. Itsfuture lies ahead of it, unless it is cut offor not permitted to develop its inherentcapacities. Therefore, defenders of em-bryonic human life insist that the em-bryo is not a ‘potential life,’ but is rath-er a life with potential. It is a potentialadult, in the same way that fetuses, in-fants, children, and adolescents are po-tential adults. It has the potential foragency, just as fetuses, infants, and small

children do. Just like human beings inthe fetal, infant, child, and adolescentstages, human beings in the embryonicstage are already, and not merely poten-tially, human beings.20

In an essay in the New England Journal ofMedicine, Harvard political theorist Mi-chael Sandel claimed that human em-bryos are different in kind from humanbeings at later developmental stages.This argument truly takes us to the heartof the matter: is a human embryo a hu-man being? At its core is this analogy:

Although every oak tree was once anacorn, it does not follow that acorns areoak trees, or that I should treat the loss ofan acorn eaten by a squirrel in my frontyard as the same kind of loss as the deathof an oak tree felled by a storm. Despitetheir developmental continuity, acornsand oak trees are different kinds of things.

He maintains that just as acorns are notoak trees, embryos are not human be-ings.

Sandel’s argument begins to go awrywith his choice of analogates. The acornis analogous to the embryo, and the oaktree (he says) is analogous to the humanbeing. But in view of the developmentalcontinuity that science fully establishesand Sandel concedes, the proper analo-gate of the oak tree is the mature humanbeing, viz., the adult. Sandel’s analogyhas its apparent force because we feel asense of loss when a mature oak is felled–assuming it is a magni½cent or beau-tiful oak. But while it is true that we donot feel the same sense of loss at the de-


Embryoethics

19 Recent research has raised questions aboutwhether ‘brain death’ is always equated withthe irreversible loss of integral organic func-tioning. See D. Alan Shewmon, “The Brain andSomatic Integration: Insights into the StandardBiological Rationale for Equating ‘Brain Death’with Death,” The Journal of Medicine and Philoso-phy 26 (2001): 457–478.

20 Lee and I have replied to other argumentsthat identify the human ‘person’ as the brain or brain activity, and the human ‘being’ as thebodily animal, in Robert P. George and PatrickLee, “Dualistic Delusions,” First Things 150(2005).

struction of an acorn, it is also true thatwe do not feel the same sense of loss at the destruction of an oak sapling. Butclearly the oak tree does not differ inkind from the oak sapling.

This example shows that we value oak trees not because of the kind of en-tity they are, but because of their mag-ni½cence. The magni½cence of an oaktree reflects either accidental propertiesor instrumental worth; a mature treeprovides our house with shade and isaesthetically pleasing to behold. Neith-er acorns nor saplings are magni½cent,so we do not experience a sense of losswhen they are destroyed. If oak treeswere valuable by virtue of the kind of en-tity they are, then it would follow that itis just as unfortunate to lose an acorn asan oak tree.

But the basis for our valuing humanbeings is profoundly different from thebasis for valuing oak trees. As Sandelconcedes, we value human beings pre-cisely because of the kind of entities theyare. Indeed, that is why we consider allhuman beings to be equal in basic digni-ty and human rights. We most certainlydo not believe that especially magni½-cent human beings–such as MichaelJordan or Albert Einstein–are of greaterfundamental worth and dignity than hu-man beings who are physically frail ormentally impaired. We would not toler-ate the killing of a handicapped child ora person suffering from, say, brain can-cer in order to harvest transplantable or-gans to save Jordan or Einstein.

And we do not stand for the killing ofinfants, which on Sandel’s analogy would beprecisely analogous to the oak saplings whosedestruction we do not necessarily regret. Man-agers of oak forests freely kill saplings,just as they might destroy acorns, to en-sure the health of the more mature trees.No one gives it a second thought. This isprecisely because we do not value mem-

bers of the oak species–as we value hu-man beings–because of the kind of en-tity they are. If we did value oaks in thisway, then we would have no less reasonto regret the destruction of saplings, andpossibly even acorns, than that of ma-ture oak trees. Conversely, if we valuedhuman beings in a way analogous to theway we value oak trees, then we wouldhave no grounds to object to killing hu-man infants or even mature human be-ings who are ‘defective.’

Sandel’s defense of human embryo-killing on the basis of an analogy be-tween embryos and acorns collapses the moment one brings into focus theprofound difference between the basison which we value oak trees, and that on which we ascribe value to human be-ings. We value oaks for their accidentalproperties and their instrumental worth.But we value human beings because ofthe intrinsic worth and dignity they pos-sess by virtue of the kind of entity theyare.21

I now consider a ½nal objection. Somehave claimed that the phenomenon ofmonozygotic twinning shows that theembryo in the ½rst several days of itsgestation is not a human individual. Thesuggestion is that as long as twinningcan occur what exists is not yet a unitaryhuman being, but only a mass of cells–each cell being totipotent and allegedlyindependent of the others.

It is true that if a cell or group of cellsis detached from the whole at an earlystage of embryonic development, thedetached part can become an organismwith the potential to develop to maturityas distinct from the embryo from whichit was detached. But this does nothing toshow that before detachment the cells



21 Lee and I responded to Sandel in George andLee, “Acorns and Embryos.”


Embryoethics

within the human embryo constitutedonly an incidental mass.22

Consider the parallel case (discussedby Aristotle) of the division of a flat-worm. Parts of a flatworm have thepotential to become a whole flatwormwhen isolated from the present whole of which they are a part. Yet no onewould suggest that prior to the divisionof a flatworm, the original flatworm was not a unitary individual. Likewise, at the early stages of human embryonicdevelopment, before specialization bythe cells has progressed very far, cells orgroups of cells can become whole organ-isms if they are divided and exist in anappropriate environment after the divi-sion. But that fact does not in the leastindicate that prior to the twinning event,the embryo is other than a unitary, self-integrating, actively developing humanorganism. It certainly does not show

that the embryo is a mere “clump ofcells.”

Based on detailed studies of othermammals, it is highly likely that in the½rst two weeks, the cells of the develop-ing embryonic human being alreadymanifest a degree of specialization anddifferentiation. From the beginning,even at the two-celled stage, the cells ofmouse embryos differ in their develop-mental fates; they will ultimately con-tribute to distinct tissues within the em-bryo.23 By the four-celled stage, thereare clear molecular24 and developmen-tal25 differences between cells of thedeveloping mouse. At no time is theembryo a mere ‘ball of cells,’ i.e., a col-lection of homogeneous cells that do not function together as an organismicwhole.

Now some people have claimed thatthe human embryo does not become a human being until implantation, be-

22 William Hurlbut of Stanford University has pointed out that “[m]onozygotic twinning(a mere 0.4 percent of births) does not appearto be either an intrinsic drive or a random pro-cess within embryogenesis. Rather, it is a dis-ruption of normal development by a mechani-cal or biochemical disturbance of fragile cellrelationships that provokes a compensatory re-pair, but with the restitution of integrity with-in two distinct trajectories of embryologicaldevelopment.” He goes on to explain that “thefact that these early cells retain the ability toform a second embryo is testimony to the re-siliency of self-regulation and compensationwithin early life, not the lack of individuationof the ½rst embryo from which the second canbe considered to have ‘budded’ off. Evidencefor this may be seen in the increased incidenceof monozygotic twinning associated with ivf

by Blastocyst Transfer. When ivf embryos aretransferred to the uterus for implantation at the blastocyst stage, there is a two- to tenfoldincrease in the rate of monozygotic twinning,apparently due to disruption of normal organis-mal integrity.” Human Cloning and Human Digni-ty: An Ethical Inquiry, Report of the President’sCouncil on Bioethics, Washington, D.C., July2002, personal statement of William Hurlbut.

23 For example, the plane of cleavage of thezygote predicts which cells will contribute tothe inner cell mass and which will contribute to the trophectoderm; B. Plusa et al., “The First Cleavage of the Mouse Zygote Predicts the Blastocyst Axis,” Nature 434 (7031) (March17, 2005): 391–395; R. L. Gardner and T. J. Da-vies, “The Basis and Signi½cance of Pre-Pattern-ing in Mammals,” Philosophical Transactions ofthe Royal Society B: Biological Sciences 358 (2003):1338–1339; J. Rossant and P. P. Tam, “EmergingAsymmetry and Embryonic Patterning in Ear-ly Mouse Development,” Developmental Cell 7(2004): 155–164.

24 M. E. Torres-Padilla et al., “Histone Argi-nine Methylation Regulates Pluripotency in the Early Mouse Embryo,” Nature 445 (7124)(January 11, 2007): 214–218; J. A. Stanton, A. B.Macgregor, D. P. Green, “Gene Expression inthe Mouse Preimplantation Embryo,” Reproduc-tion 125 (2003): 457–468.

25 K. Piotrowska-Nitsche et al., “Four-CellStage Mouse Blastomeres Have Different De-velopmental Properties,” Development 132 (3)(February 2005): 479–490.

cause (they assume) the embryo can-not establish a basic body plan until itreceives external maternal signals at im-plantation. Only then is it a self-direct-ing human organism. According to thisview, these signaling factors somehowtransform what was hitherto a merebundle of cells into a unitary human or-ganism.

However, embryologists argue aboutwhether any such maternal signalingactually occurs. As Hans-Werner Denkerobserved, it was once assumed that inmammals, in contrast to amphibiansand birds, polarity in the early embryodepends upon some external signal,since no clear indications of bilateralsymmetry had been found in oocytes,zygotes, or early blastocysts.26 But thisview has been revised in the light ofemerging evidence: “[I]ndications havebeen found that in mammals the axis of bilateral symmetry is indeed deter-mined (although at ½rst in a labile way)by sperm penetration, as in amphibians.Bilateral symmetry can already be de-tected in the early blastocyst and is notdependent on implantation.”

Denker refers speci½cally to the workof Magdelena Zernicka-Goetz and hercolleagues at Cambridge University, andthat of R. L. Gardner at Oxford Univer-sity, which show that polarity existseven at the two-celled stage. In contrast,Davor Solter and Takashi Hiiragi of theMax Planck Institute for Immunobiolo-gy in Freiburg argue that in the early em-bryo (prior to compaction and differen-tiation into inner cell mass and tropho-blast), external factors determine thefate of each cell, rather than an internal

polarity.27 In other words, the issue isnot de½nitively settled. However, which-ever of the two is true, it is less than can-did for anyone to assert the older viewwithout acknowledging that credible sci-entists from leading universities havepublished research contradicting it inmajor peer-reviewed scienti½c journals.

Moreover–and here is the most im-portant point–even if it is the case thatpolarity does not emerge until a mater-nal signal is received at implantation,that would not provide any evidence that such a signal transformed a bundleof cells into a unitary, multicellular hu-man organism. Just as the lungs begin tobreathe at birth only in response to cer-tain external stimuli, so it would makesense (if the older view is true) that dif-ferentiation into the rudiments of thedistinct body parts (basic bilateral po-larity) would begin only in response tosome external stimuli. And this is exact-ly how embryology texts interpretedsuch signals, even prior to the publica-tions of Zernicka-Goetz and Gardnerand their teams.

There is much evidence that the hu-man embryo is from the ½rst day on-ward a unitary organism, and never amere bundle of cells. Development inthe embryo is complex and coordinated,including compaction, cavitation, andother activities in which the embryo ispreparing itself for implantation.

And here is the clearest evidence thatthe embryo in the ½rst two weeks is not a mere mass of cells but a unitary organ-ism: if each cell within the embryo be-fore twinning were independent, therewould be no reason why each would notdevelop on its own. Instead, these alleg-edly independent, noncommunicating



26 Hans-Werner Denker, “Early Human De-velopment: New Data Raise Important Embry-ological and Ethical Questions Relevant forStem Cell Research,” Naturwissenschaften 91 (1)(2004): 21 ff.

27 See Gretchen Vogel, “Embryologists Polar-ized Over Early Cell Fate Determination,” Sci-ence 308 (May 6, 2005).

cells regularly function together to de-velop into a single, more mature mem-ber of the human species. This factshows that the cells are interacting fromthe very beginning (even within thezona pellucida, before implantation), re-straining them from individually devel-oping as whole organisms and directingeach of them to function as a relevantpart of a single, whole organism contin-uous with the zygote. The evidence indi-cates that the human embryo, from thezygote stage forward, is a unitary humanorganism.28

Supporters of embryo-destructive re-search have advanced other argumentsagainst the proposition that humanembryos are embryonic human beingsbearing basic dignity and full moralworth. I have focused in this essay on the strongest arguments against my po-sition and laid aside the weaker ones,such as those proposing to infer some-thing of moral relevance from the factthat human embryos are tiny and not yet sentient; or from the fact that a highpercentage of human embryos are natu-rally lost early in pregnancy; or from the claim that people typically either do not grieve for the loss of embryos inearly miscarriages, or grieve but not asintensely as they do for children who dielater in gestation or as infants.

If there is a valid argument to showthat human embryos are something oth-er than human beings in the embryonicstage of development, or that embryon-ic human beings lack the basic dignityand moral worth of human beings inlater developmental stages, it is one ofthe arguments I address here. I have giv-en my reasons for believing that none of

these arguments can withstand criticalscrutiny.

The debate about the value of embry-onic human life is sure to continue. Butif that debate is informed by serious at-tention to the facts of embryogenesisand early human development, and ofthe profound, inherent, and equal digni-ty of human beings, then we, as a nation,will ultimately reject the deliberate kill-ing of embryonic humans, regardless ofthe promised bene½ts.

This does not necessarily mean wemust sacri½ce such bene½ts. Scientistshave already made tremendous prog-ress toward the goal of producing fullypluripotent stem cells by non-embryo-destructive methods. If such methodsare pursued with vigor, the future mightsee the promise of stem cell science ful-½lled, with no stain on our national con-science.


Embryoethics

28 Lee and I presented this information inGeorge and Lee, “The First Fourteen Days ofHuman Life.”

Robert P. George Embryo ethics - Stand to Reason …research or therapy if they could be ob-tained from non-embryonic sources, or if they could be acquired by using em-bryos lost in

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