Human-Embryo Liberation
A reply to Peter Singer


In a pair of highly publicized articles, the South Korean scientist Hwang Woo-Suk claimed to have produced human embryos by cloning and to have generated from them several viable stem-cell lines. Hwang’s work was heralded by supporters of embryonic-stem-cell research as a great step toward the goal of using embryonic stem cells to treat diseases and afflictions. What had them excited was Hwang’s claim to have produced stem cells that match the DNA of the somatic cell’s donor, thus defeating (or substantially diminishing) the number-one problem faced in transplant procedures, namely, the rejection by the body’s immune system of genetically foreign tissues or organs.

Right before Christmas, however, The Seoul National University panel released the first part of its report on the veracity of Dr. Hwang’s research, and concluded that his results were “intentionally fabricated.” (See the report here.) This was the most recent in a series of scandals involving Dr. Hwang that have put advocates of so-called “therapeutic” cloning on the defensive. Some are fighting back, however, not by defending Dr. Hwang, but by saying that his fraudulent and admittedly unethical actions are simply irrelevant to the question at the heart of the debate: Is it ethically legitimate to produce human embryos, by cloning or other processes, for the purpose of biomedical research in which they are deliberately destroyed?

In the vanguard is Professor Peter Singer, who has gone a step further. Noting that “few researchers doubt that what Hwang claimed to do is in principle achievable,” Singer asserts that the basic pro-life argument against killing embryos is decisively undermined by the prospect of someone actually accomplishing what Hwang and his team (fraudulently) claimed to achieve (see the Australian, December 23). The crucial premise of the pro-life argument is that human embryos are distinct and unique human beings in the earliest stage of their development and, as such, possess inherent dignity. According to Singer, “it is precisely this reasoning that is threatened by what Hwang and his team claim to have achieved.”

Embryonic Essentials

For now, let us set aside the fraudulence of Hwang’s claim, for it may well be true that some scientists in the future will actually clone human beings. However, the idea that the possibility of human cloning casts doubt on the central argument against embryo killing is groundless. Echoing an argument advanced previously by Oxford philosopher Julian Savelescu and Reason magazine writer Ronald Bailey among others, Singer contends that “[p]roving the possibility of cloning from the nucleus of an ordinary human cell would transform the debate about the value of potential human life, for we would find that potential human life was all around us, in every cell of our bodies.” This argument is doubly confused.

First, the debate is not about “potential human life”–a dubious and quite possibly incoherent notion that we and other opponents of embryo-killing reject. We contend that as a matter of basic biological fact human embryos are actual human beings in the earliest stages of their natural development. Human embryos (or fetuses, or infants) do not differ in kind from mature human beings (as carrots or alligators differ from humans); rather the difference between human embryos (fetuses, infants) and adults is a difference merely in stage or degree of development of precisely the same kind of being.

Unlike gametes (the sperm and eggs whose union might produce a new human being), and unlike somatic cells that might be used in cloning, human embryos have within themselves not only all [of] the organizational information needed but also the active disposition to use that information to develop themselves to the stage of a mature human being. If provided a suitable environment and nutrition, and barring accident, disease, or intentional violence done to them, these nascent human beings will grow by an integrated, self-directed process, through the fetal, infant, toddler, child, and adolescent stages of human maturation, and into adulthood, with their identity and distinctness intact. Thus, each one is now the same human individual, the same substantial entity, that may later crawl, then walk, then talk, then reason, make choices, and perform the actions characteristic of mature human beings.

It is wrong to kill an adult, not because he or she has achieved a certain degree of development, but because of what (i.e., the kind of entity) he or she is, namely, a human being. (That is an implication of the moral fact that human beings possess inherent dignity as entities with a rational nature–we provide support for this proposition below, the last three paragraphs). So, the human being possesses dignity and a right to life from the time he or she comes to be; and he or she comes to be either at fertilization, in the case of sexual reproduction, or with the successful completion of the process of somatic cell nuclear transfer, in the case of cloning. (Again, we are assuming for the sake of argument that the production of a human embryo by cloning will eventually prove to be technically possible. Perhaps we should here register our opinion that the production of human beings by cloning, whether to be destroyed in the embryonic stage for scientific research or implanted in the uterus of a woman or in an artificial womb and brought to birth, would be morally wrong.)

The second confusion in Singer’s argument is that it rests on a false analogy between human embryos and somatic cells. Singer contends that the pro-life case rests on the argument that human embryos have a right to life because they have the potential to become mature human beings. He claims that the argument is falsified by the possibility of human cloning, which shows that any ordinary body cell, such as a skin cell or a muscle cell, also has such a potentiality–it only needs to be placed in the right environment, an enucleated ovum, to begin growth toward maturity. Singer’s argument fails, however, because the “potentiality” in a somatic cell (due to the possibility of cloning) is radically different from the active disposition in a human embryo to develop itself toward the mature stage of what he or she (sex is determined from the beginning) already is–a human being. If one thinks of cloning as analogous to sexual reproduction, somatic cells that may be used in the process are analogous not to embryos, but to the gametes which, when united, cease to exist but whose constituents enter into the creation of a new and distinct human being. Human cloning, if successful, would produce just what is produced by the union of sperm and egg, namely, a complete human organism–a human being–in his or her initial (embryonic) developmental stage.

Fusing the nucleus of a somatic cell to an enucleated ovum (ordinarily achieved with the aid of an electrical stimulus) does more than merely place an entity in an environment suitable for its self-development. Because successful cloning generates an entirely new and distinct substantial entity (indeed, it generates an embryonic human being), it is simply false to say that a somatic cell has the potential to become a mature whole human being. In the cloning process, the somatic cell (or its nucleus), which is part of a larger organism, ceases to be, and its constituents enter into the make-up of a new and distinct organism, a new member of the species that is cloned (e.g., sheep, mouse, or human, if that should occur). By contrast, when the embryo grows, it continues to be, and simply matures. You and I once were human embryos, just as you and I once were adolescents, children, toddlers, infants, and fetuses. But a cloned animal organism, such as Dolly the sheep, never was a somatic cell, and so too a cloned human being would not come to be until the cloning process was successfully completed. Thus, a human embryo does, but a somatic cell does not, have the potentiality–in the sense of active disposition and intrinsic power–to grow (indeed, to self-develop) toward the mature stage of a human being.

Moreover, each human embryo is a distinct, whole (though obviously immature) human being. But each somatic cell is only a part of a larger whole, only a part of a human being. Should some scientists actually succeed in cloning human beings, this will show only that parts of cells (the nucleus of a somatic cell and the enucleated ovum) can be joined to each other in a way that produces a distinct, whole human being. The human embryo is a whole human being; the somatic cell is only a part of a human being. So Singer’s argument by analogy collapses.

Singer quotes President Bush, who said: “Like a snowflake, each of these embryos is unique, with the unique genetic potential of an individual human being.” Singer then replies that, “If it is the uniqueness of human embryos that makes it wrong to destroy them, then there is no compelling reason not to take one cell from an embryo and destroy the remainder of it to obtain stem cells, for the embryo’s unique genetic potential would be preserved.” But the president’s argument was not that what makes a human embryo (or any human being) valuable is its uniqueness or its unique genetic code (nor does anyone we know argue that). After all, every numerically distinct entity, such as each grain of sand, or each singular newspaper, is unique, that is, distinct from every other entity; and the genetic code by itself is preserved in the cells in a corpse.

What President Bush said was that each embryo has “the unique genetic potential of a human being” (emphasis added)–and that is why he or she is not an ethically appropriate subject for experimentation and dismemberment (including dismemberment into constituent cells or genetic materials) for the sake of others. Uniqueness by itself is not, of course, the basis of intrinsic value as a subject of rights. Rather, uniqueness can enter the argument in two ways. First, the human embryo’s genetic uniqueness shows that the embryo is not part of a larger organism. Even clones and monozygotic twins are epigenetically distinct, that is, in each the methylation of the genes, that is, the order of gene expression, is distinct. Second, each human being is uniquely valuable, in the sense that each is ethically irreplaceable: because a person is not merely good as a means to other ends, but is intrinsically good as a subject of rights, i.e., valuable for his or her own sake. A person is not like a newspaper or a candy bar, he or she cannot be replaced by another just like it without loss of value.

Finally, near the end of his article, Singer says that if arguments from potential fail then the argument against killing embryos “must be based on the nature of those entities themselves: that they are actual human beings who already possess the characteristics that make killing wrong.” However, he then claims that since embryos and fetuses have yet to develop any kind of consciousness, killing them “is much less serious than killing a normal human being.”

Singer voices here perhaps the most popular argument in favor of embryo-destructive research and abortion. Few who accept this argument have followed it to its logical conclusion, however, as Singer has: If self-awareness is the ground of general immunity of being killed right not to be killed, not only abortion but also infanticide, and the killing of many helpless adults, are morally legitimate (see Singer’s popular textbook, Practical Ethics, Chapters 2 and 4). In fact that conclusion is inescapable once one accepts Singer’s premise. But one has decisive reasons to reject that premise as fatally flawed. It is true that an embryo or fetus (or infant) lacks the immediately exercisable capacity for self-awareness, rationality, or free choice. Yet, the embryo or fetus does have the basic, natural capacity for such actions as consequent to its nature, that is, as entailed by the kind of entity it is. The embryo or fetus, precisely in virtue of the kind of entity he or she is, has the capacity to develop himself or herself to the point where he will perform such actions. And no one has been able to give an intelligible reason why we should base full moral rights on immediately exercisable capacities–which can come and go–rather than on the basic, natural capacities that a human being at any stage of development has in virtue of the kind of entity it is. (Of course, the full development of these capacities can be impeded from an early stage, as in the case of persons afflicted by certain severe congenital forms of retardation or impeded later in life by senility or other forms of dementia, none of which transforms human beings into subhuman creatures

Moreover, a person in a coma (even if it may prove to be reversible) also lacks the immediately exercisable capacities for such actions, but he surely has a right to life. This suggests that it is not the immediately exercisable capacities that count, but the nature of the entity that is important. It is wrong to kill a person in a coma because he is a being with a rational nature–that is, he is a substantial entity that is internally oriented to reasoning and shaping his own life by rational deliberation and choice. But this is true also of the human embryo or fetus.

Some entities have intrinsic value and basic rights and other entities do not. Such a radical moral difference logically must be based on a radical ontological difference (that is, a radical difference among those entities themselves). And so the basis for that moral difference (a difference in the way they should be treated) must be the natures of those entities, not their accidental characteristics which involve merely quantitative differences, or differences in degree. (By “accidental” qualities, we mean those attributes that do not help to define the nature of an entity. In humans, age, size, stage of development, state of health, and so forth are accidental qualities.) The immediately exercisable capacity to reason and make free choices is only the development of the underlying basic, natural capacity for reasoning and free choice, and there are various degrees of that development along a continuum. But one either is or is not a distinct subject with a rational nature (the traditional definition of “person”). So, Singer is correct to say that the right to life must be based on what is true of the entity now, not just what is true of its future. But it is true of the human embryo now that he or she is a distinct individual with a rational nature, even though it will take him or her several years fully to actualize his or her basic, natural capacities so [that] they are immediately exercisable.

Our conclusion: Every human being, irrespective of age, size, condition of dependency, or stage of development–or the means by which he or she is produced–is intrinsically valuable as a subject of rights and deserves full moral respect. .

Patrick Lee is a professor of philosophy at the Franciscan University of Steubenville & Robert P. George is a professor at Princeton University.


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