The announcement of the Bush administration’s human embryonic stem cell research funding policy in the summer of 2001 certainly did not end the debates surrounding the issue. The policy offered a particular target to which participants in the debate could react, but the basic questions involved in assessing how the federal government should approach embryonic stem cell research remained just as relevant, and just as controversial, as they had been before. In this chapter, we offer an overview of that still continuing debate as it has developed in the past two years. Without attempting to provide anything like a full account of different positions and arguments, we hope, rather, to point to the major items under argument—to the issues that any interested citizen might wish to ponder. First, we will outline the general form of the moral argument as it has developed over time. Second, we will discuss specific questions and critiques regarding the current policy, as those have emerged in public discussion. Third, we will review the various positions on the moral standing of human embryos, seeking again to outline the chief fault lines in that continuing debate. And finally, we will highlight some critical ethical concerns that do not arise directly out of the debate over the moral standing of human embryos but that may be no less important to the larger question confronting the country.

This array of subjects includes both some that are clearly ethical questions and some that may fall closer to questions of policy. We take up both together because we believe both are essential to a full understanding of the issues involved and because even the policy debates—as understood and engaged in by participants on all sides—are clearly directed to a set of underlying moral issues and informed by ethical beliefs and opinions. Critiques (and defenses) of the present policy, and proposals of alternatives, are almost without exception based on moral grounds.

This chapter will, of course, revisit several of the themes raised in the previous chapter. There, our aim was to present some basic facts regarding the current policy, its context, and its execution. Here, we take up arguments on all sides of the issue—including those that dispute the understanding of the policy put forward by its authors and those that raise other issues or alternative courses of action.

While we will raise these arguments and counterarguments, examining problems, questions, and concerns, our purpose is not finally to assess the validity of the competing claims or to arrive at a conclusion, but—in line with the Council’s charge to monitor developments in this area—to present them more or less as they have appeared in the public debates of the past several years. This way of proceeding suffers from one especially prominent drawback: it tends to present all arguments as equal in importance or prevalence. We will seek to avoid this whenever possible, by offering some sense of which arguments have been most crucial for the public debate.

I. The Nature of the Moral Argument

Before entering upon a detailed review of the debates, we take a moment to consider the character of the moral reasoning and argumentation we will confront. Different participants in the stem cell debates tend to hold different views not only regarding individual substantive judgments, but also regarding the kind of moral question, in the most general terms, we are facing in deciding about stem cell research policy. At first glance, people seem to be disagreeing about whether a balancing of competing interests and goods is called for, or whether some one overriding moral duty ought to shape our judgment, though of course that dichotomy is not in every case quite so stark.

In casual conversation, and sometimes in more theoretical reasoning, moral questions are often analyzed in the language of “weighing” and “balancing,” or else in terms of overriding concerns, inviolable principles, or fundamental “rights.” These two sets of terms and metaphors point to two distinct ways of making difficult moral judgments. In some circumstances there need be no irresolvable conflict between the two approaches. Those who seek to respect fundamental rights and adhere to inviolable principles need not ignore the complexities of moral situations or the consequences of our actions when they form their judgments. Likewise, those who seek to weigh or balance competing goods may think of those goods as involving not only benefits to be realized but also principles to be upheld. There may also be circumstances, however, in which those differences that do exist between these two approaches constitute a fork in the road, constraining our decision. Thus, to take an example from outside the domain of bioethics, the principle that civilians should be safeguarded from direct, intended attack in time of war may be understood to trump all other competing goods (without denying the importance of those goods), or it may be understood as one good to be balanced against others. Which fork in the road of moral reasoning one takes at such a point will have a decisive influence on the character of the arguments employed and the conclusions reached.

This has often also been the case in the public debate over federal funding of human embryonic stem cell research. Many observers have agreed that federal policy must seek a certain balance between two competing goods or interests: the progress of medical research and therapy, and respect for nascent human life. Indeed, President Bush himself framed the issue in these terms, saying a few weeks before his decision was announced that his policy would “need to balance value and respect for life with the promise of science and the hope of saving life.”¹ But not all participants in the debate have had the same idea of what such balance should entail and, therefore, how weight should be assigned to the competing demands.

For some, the degree of medical promise should profoundly affect the degree of government support for embryonic stem cell research. For them, the critical element (though of course not the exclusive one) in establishing policy must be scientific data about what might be achieved with human embryonic stem cells.² The greater the promise of the research, the more support it should receive and the more it should outweigh reasons offered for opposing the techniques involved.³ On this view, the concern given greatest prominence and weight in reaching a judgment ought to be the very great good of medical progress toward the relief of suffering. Most of the arguments in favor of increased taxpayer funding of embryonic stem cell research have begun from this premise—explicitly or implicitly—and have proceeded by laying out the possible medical benefits of the research or the possible harms (to patients or to American science) of withholding support. We shall review a number of these lines of argument in more detail below. But it is worth noting at the start that most of them tacitly assume that the policy decision at hand ought to be based on a reasoned balancing of crucial concerns—all of which matter but none of which simply overrides the others.

Others, however, have suggested that at least a substantial portion of the opposition to the research rests upon the belief that human embryos should not be violated and therefore—if this claim is valid—that the threat to their life and worth cannot be justified by the promise of research.⁴ It follows, on this view, that the federal government should do nothing to encourage or support the future destruction of human embryos, regardless of the promise of research. What remains then to be considered is the extent to which the government might advance the additional aim of progress in medical research within the bounds of the principle.⁵ In this case, the moral reasoning is understood to be decisively affected by an unbreachable boundary, and only the extent of some particular provisions of the policy are left to be settled by a weighing and balancing of other priorities. Proponents of the various forms of this position generally argue that the claim of human embryos to our protection presents us with a fundamental duty, to be overridden, if at all, only in extreme circumstances, rather than with just one good to be balanced off against others.⁶

In presenting the matter this way, adherents of this view consciously appeal to the ethics governing research with human subjects, which obliges those engaged in efforts to advance knowledge and seek cures to keep from trespassing upon human safety, freedom, and dignity.⁷ The decades-old and nearly universal adherence of researchers to rules protecting human subjects, these commentators suggest, demonstrates that the needs of research are not always treated as paramount and that the scientific community itself joins the general public in recognizing instances in which research—however important—must be limited for ethical reasons.⁸ Researchers do not weigh the interests of human subjects against the importance of their work; rather they respect a principled boundary—that human subjects are not to be harmed or put at risk without their informed consent—the importance of which trumps even the most promising experiment. For some defenders of human embryos, the prospect of embryo research raises precisely these concerns; accordingly, they argue that this issue too should be decided on the basis of a moral rule, not by a shiftable tally on a balance sheet of benefits.⁹

But this assertion about the proper form of moral argument depends on the truth of the claim that human embryos are indeed human subjects of research. Therefore, one’s position in the debate about the basic character of the moral issue may depend, in many cases, on one’s understanding of the moral standing of human embryos. As we shall see, the question of the moral standing of embryos is by no means the only relevant question. But in the actual public debate, as it has developed, this question seems to have been most central and prominent and probably most responsible for shaping the different basic approaches pursued. It is this question that very often informs the differing views regarding which aims or goods are more weighty or which should not be compromised at all.

We turn next to arguments regarding that very issue: Which moral aims or which concerns should be given priority in shaping government policy toward human embryonic stem cell research?

II. The Moral Aims of Policy

A significant part of the public debate surrounding the policy governing funding of embryonic stem cell research has involved differing views of just which purposes or ideals should most directly guide policymakers in this arena. The current funding policy—while it appears to strike some balance between protecting human embryos and advancing biomedical research—seems to take as its overriding concern the insistence that the federal government not encourage or support the deliberate violation or destruction of human embryos. But a number of commentators in recent years—and, of course, particularly those who ascribe lesser moral status to human embryos—have proposed alternative principles to govern policy.

A. The Importance of Relieving Suffering

Many observers argue that the proper governing principle should be the duty to relieve the pain and suffering of others—the purpose that ultimately motivates the work of biomedical science. This aim is broadly, perhaps universally, shared. Indeed, the current policy, as outlined by its advocates, while it seeks to protect nascent human life, explicitly seeks to advance medical research as far as its authors believe is morally permissible. Some commentators argue, however, that the administration has chosen the wrong one of these aims as the governing principle of its approach.

The cause of curing disease has a human face, the face of a loved one or neighbor, bent under the suffering of an incompletely understood or treated disease. As a result, the aspiration to know is linked to a desire to relieve. How, wonder many commentators, could anyone think of withholding support for research that might yield therapies for devastating diseases and conditions such as spinal cord injury, diabetes, and Parkinson disease?¹⁰ Surely, they argue, the pain and suffering of those in need should outweigh concerns for human embryos frozen in a laboratory.¹¹ Indeed, for many this is an especially critical issue in light of the likely ultimate fate of these embryos. Will they be frozen indefinitely? If not, then will they be thawed out and discarded and destroyed, or used to potentially benefit mankind?
One form of this argument, heard increasingly over the past few years, begins with data about disease prevalence and suggests that anyone who obstructs public funding of research that might someday help patients suffering from such diseases must bear some of the responsibility for their future suffering and (perhaps) death.¹² Some opponents have countered that any assertion that makes relief of human suffering the highest moral principle to this extent might logically impugn any and all deflection of resources into less ultimate concerns such as recreation, beautification, or social ceremony. Others respond more directly that an unwillingness to violate one’s moral principles in order to help relieve the sick does not make one responsible for their sickness.¹³

In most cases, however, the arguments for grounding federal funding policy in the importance of biomedical research do not blame opponents for the suffering of the sick. Rather, they focus on the promise of bringing relief to those who most need it. They point to the immense benefits already delivered to us by modern medicine and argue that the federal government should advance this cause in whatever ways it reasonably can. Many advocates of this view agree that nascent human life should receive respectful treatment, but they argue that the claims of our duties to human embryos—whether in general or in particular circumstances, like those stored in fertility clinic freezers—cannot simply trump the claims of promising medical research and our duties to suffering humanity. The obligation to aid the sick, they contend, and the fact that the research in question might relieve the pain and terrible suffering of countless patients and their families, should lead us to do all that can reasonably be done to find treatments and cures, and to offer help. This does not mean simply ignoring the significance of human embryos, or taking lightly the decision to destroy them in research, but, they suggest, it should mean taking seriously the moral calling to help the suffering and deciding how to proceed based on more than one sort of obligation.¹⁴

In response, one commentator has argued in broad terms against the underlying assumption that the demands of biomedical research should somehow be seen as “imperative.” Such work, he contends, should not be seen as inherently and always obligatory, and claims to support it may be overridden even by a level of respect for nascent human life that does not suppose that embryos possess full human moral standing. He suggests that it is not at all obvious that individuals or the government have a definite responsibility to support such research or that such a responsibility would override other moral duties.¹⁵

Others point out that the duty to find cures for disease cannot be an unqualified or absolute imperative. Pointing to the present rules governing the treatment of human subjects in research, they argue that the case for embryonic stem cell research cannot rest on an alleged and overriding imperative to pursue that research. These rules prohibit certain sorts of procedures on human subjects of research, and the same, they suggest, should be required in stem cell research. Yet those who argue that the importance of medical research and treatment should override the aim of protecting human embryos presumably would not propose to override protections for human subjects in research on children or adults. Rather, they approach the present matter differently because they do not consider human embryos the developmental, anthropological, or moral equivalent of children or adults, or worthy of the same protection. The difference, therefore, has to do not so much with a dispute over the imperative importance of research, but rather (at least to a significant extent) with the status of nascent human life, which again turns out to be the fundamental point at issue.¹⁶

Nevertheless, the moral claims of medical research and treatment are extremely powerful in the debate over human embryonic stem cell policy, and they are acknowledged as profoundly important even by those who do not finally take them to be decisive. Most arguments in opposition to the present funding policy and in support of expanded embryonic-stem cell research are grounded in these claims.

B. Freedom to Conduct Research

Other opponents of the present policy argue not from the value of medical benefits but on the basis of freedom to conduct research, which they believe is the principle by which federal policy ought to be governed. They regard government restraints on scientific research as inherently offensive and generally unjustifiable.¹⁷ The cherished ideals of freedom of thought, freedom of conscience, and—specifically in this context—freedom of inquiry, trump concerns over the moral status of human embryos, they contend.¹⁸
The most common claim advanced for protecting research as a basic right (employed, among others, by the American Bar Association) involves some form of an appeal to the First Amendment’s protection of free speech, interpreted through the years by the Supreme Court to encompass free expression and perhaps freedom of inquiry and thought.¹⁹ Some argue that research is a form of expression, particularly when it is politically or socially controversial, and when restraints upon it are imposed for moral reasons.²⁰ “One could make the case that research is expressive activity and that the search for knowledge is intrinsically within the First Amendment’s protection for freedom of thought,” says one ethicist.²¹

Others, however, contend that this claim, never tested in the courts, seems far-fetched. Most currently controversial biological research involves experimental manipulation of living matter, rather than theoretical exploration or mere observation of natural objects. It is therefore as much action as expression, as much creation as inquiry. It is difficult to see, they argue, how such activity (as opposed to the reporting of the results of such activity) could be classified as a form of expression. “Scientists may have the right to pursue knowledge in any way they want cognitively, intellectually,” argues one observer, “but when it comes to concrete action in the lab, that becomes conduct and the First Amendment protection for that is far, far weaker.”²²

Moreover, argues at least one commentator, even if one did stipulate that research activity is to be protected from governmental proscription or restriction, it is far from clear that failure to provide federal funding would constitute such a restriction.²³ Indeed, legislative and judicial precedents suggest it would not. The government routinely refrains from funding activities it otherwise permits or even guards as constitutionally protected. A line of Supreme Court decisions stretching from 1977 to 1991, dealing with abortion and government funding, established the principle that the Constitution does not require the government to fund even those activities that the Constitution protects.²⁴ Because the only issue in the present debate is one of federal funding, the protected status of scientific activity seems not to be a determining factor.²⁵

Finally, some critics of the case for a paramount right to research point again to the fact that scientific research—conducted both with private and (especially) with government funding—is already subject to certain restrictions, particularly with regard to protecting human subjects. The proposition that embryo research should not be subject to the same restrictions hinges on an argument about the standing of human embryos, rather than about the unrestrictable standing of research as such.²⁶ Once more, an important part of the question turns on the status of extra-uterine human embryos.

C. The Moral Standing of Human Embryos

However they approach the matter, then, many people engaged in the debate over federal funding policy find they must consider the fundamental question of the moral standing of human embryos: What are early human embryos, and how should we regard them morally? Approaches to the question of federal funding of embryonic stem cell research that propose some other guiding principle—relief of suffering, freedom of research—seem almost by necessity to assume that human embryos do not possess the same human moral standing as persons already born.²⁷ Conversely, if human embryos ought rightly to be treated as inviolable—as some have argued—then questions of balancing other goods or giving priority to other principles are largely rendered moot. Thus, to many observers, some of the central questions in this arena would appear to be those that surround human embryos: How ought we to think about and act toward human embryos? Should all ex vivo human embryos be treated the same, or are some, because of their circumstances, origins, or prospects, to be treated differently from others? Or are embryos of sufficiently little moral significance that we should simply decide the funding question solely on the basis of the merits and promise of the proposed biomedical research?
We shall, in due course, review the recent arguments on these critical questions. But before doing so, we examine a series of other more specific objections to the present policy. These arguments recognize that the current policy rests on the conviction that federal funds should not support or encourage the violation or destruction of human embryos. Rather than disputing this premise, a number of commentators—including both supporters and critics—have assessed the policy on its own grounds and judged it against its own claims and terms. As a result, several general categories of criticism of the policy itself have emerged.

III. The Character of the Policy

In addition to debating which aims ought to guide federal policy, many observers in the past two years have also assessed the particulars of the present funding policy, considering them in scientific, political, and moral terms. Critics have generally found fault with the policy through one or more of three general lines of argument: that it is arbitrary, that it is unsustainable, and that it is inconsistent. Defenders of the policy, meanwhile, have usually sought to counter these critics on these terms and to rebut these assertions and criticisms.

A. Arbitrary

One quite common line of argument criticizes the present funding policy as essentially arbitrary, because it relies on what is deemed a capricious cutoff date. Cells derived from embryos destroyed on August 9, 2001 are eligible for federal funding, but those obtained from embryos destroyed the next day are not. The only difference is the date of embryo destruction, argue some critics, and what moral difference could that possibly make? If the policy of funding human embryonic stem cell research serves a genuine good, these commentators suggest, would it not be equally good regardless of when the cell lines were derived? Would it not, therefore, make sense to permit funding for all cell lines derived on either side of the date, provided they are otherwise eligible?²⁸ If, on the contrary, federal funding of embryo research is unacceptable, then it should simply not be allowed at all, regardless of when cell lines were first derived.²⁹ “It is difficult to see,” writes one critic, “what ethical reasoning would commend a policy that takes as its central distinction the time chosen for political convenience to deliver a presidential address.”³⁰

In response, some supporters of the policy contend that while the cut-off date (August 9, 2001) certainly has no inherent moral significance, it acquires moral meaning by the simple fact that it was the operative date of a newly announced policy that turned on a crucial distinction between the “up-until-now” and the “from-now-on,” between past (irrevocable) deeds and future (preventable) ones. That date of announcement was the line between past embryo destruction, which could no longer be undone, and future embryo destruction, which could still be influenced by the federal government’s funding rules. If the policy sought to avoid encouraging or offering incentives for any future destruction of human embryos, they argue, then drawing a hard line between past and future would be indispensable. That line could only reasonably be drawn at the moment of the decision’s announcementⁱ (or before it), since drawing it at some point in the future would create a powerful incentive to quicken the pace of work until the cut-off date arrived. The date, they say, is therefore not a morally arbitrary marker in the context of the policy, but is rather a crucial and unavoidable element of the policy’s logic.³¹

B. Unsustainable

A further, and more common, critique of the current policy suggests that its approach cannot be expected to hold over time and that it will fairly quickly prove unsustainable.

One form of this argument suggests that the policy has created a situation in which scientists may make some progress using existing stem cell lines but would then be prohibited from capitalizing on what they have learned and making further progress using stem cell lines not now eligible for federal funds. As the editors of the Washington Post put it: “Mr. Bush’s compromise policy will be a reasonable one only as long as the existing lines are capable of supporting the research scientists need to perform.”³² Indeed, some have argued that by explicitly encouraging and speaking of the potential medical value of human embryonic stem cell research, the President himself created the circumstances that will make the constraints of the policy unsustainable. “Bush’s decision was at its core an endorsement of the promise of human embryonic stem cells and their importance to the fledgling field of regenerative medicine,” wrote one critic, and if that is the core message of the decision, then the resulting policy seems insufficient.³³

Others, arguing on more practical grounds, claim that, regardless of the reasonableness of the principle behind the policy, its effects will prove unbearable for American scientists, who will then force a reconsideration.³⁴ The limits placed on funding in the current policy, several observers have predicted, will seriously hamper and hold back embryonic stem cell research work in the United States, perhaps causing prominent scientists to leave the country in search of greater support abroad.³⁵ If that were to occur, it is argued, the policy would prove genuinely damaging to American science, and therefore to the national interest, and would need to be changed.³⁶

In response to this specific point, some defenders of the policy have noted that for the time being there has not been news of any notable migration of prominent stem cell researchers to foreign countries, that federal funding is now available with no ceiling on its amount, and that American researchers can continue to work with private funds.³⁷

But even apart from worries about a “brain-drain” in the field, some have argued that both the lack of funding, and particularly the complexity of the set of conditions under which research using such funding may be conducted, is preventing progress in research and discouraging even private funding in the field,³⁸ and that the lines made available simply will not be enough,³⁹ or indeed that they have already proved insufficient.⁴⁰ Some argue that the very low number of applications submitted to the NIH for postdoctoral and training projects using the approved stem cell lines provides striking evidence for the chilling effect of the current “in limbo” situation. Some have also suggested that safety issues connected with the way the eligible lines have been derived and developed may make them less suitable for use in human trials and treatments, thus making other cell lines necessary (although presentations before this Council by NIH Director Elias Zerhouni and FDA Commissioner Mark McClellan have contradicted some of these claims).⁴¹ Others, meanwhile, worry that the eligible lines do not offer sufficient genetic diversity to be adequate for research needs or for eventual therapies.⁴² As scientists make their case that important work is being hampered, it is argued, the policy will prove unsustainable politically and practically.⁴³

A similar argument has also been made in nearly the opposite terms. That is, some have said that if or when ongoing embryonic stem cell research produces a spectacular breakthrough in understanding or treating disease, the pressure to alter the policy would prove unstoppable.⁴⁴ This way, whether the future brings announcements of great progress, or whether it brings no news of advances, the result will be pressure for a policy that funds research more broadly.

Those defenders of the policy who have addressed these claims of unsustainability have pointed out that the present policy does not limit the amount of federal funds available to the kind of research that may be performed with the approved cell lines. They also point out that much of the pioneering work in mouse stem cell research was done using very few (approximately five) cell lines ⁴⁵ (though of course the challenge of working with human cell lines is more complex and daunting). But they have also generally pointed to the policy’s stated grounding in principle—a principle that would not change in light of scientific advances or delays. In August of 2001, for instance, Health and Human Services Secretary Tommy Thompson told reporters that “neither unexpected scientific breakthroughs nor unanticipated research problems would cause Bush to reconsider” the approach drawn by the policy, because it is based on “a high moral line that this president is not going to cross.”⁴⁶ As another observer has put it: “The general question is, well, will these cell lines be enough . . . and a non-complicity argument [like the one implied by the policy] will only work if the answer to that question is well, I guess they’ll have to be enough.”⁴⁷ Or, put differently, if the policy is founded primarily in a determination to prevent government funds from encouraging the destruction of human embryos, and only secondarily in a judgment about the value of embryonic stem cell research, then advances in research alone (or the absence of advances alone) would not be sufficient to overturn it. If it is sound before such advances, some argue, it would still be valid after⁴⁸—though again, of course, whether it is right to begin with is itself a point of great contention.

C. Inconsistent

Viewing the administration’s policy as based on an intermediate or uncertain view of the moral standing of human embryos also makes plausible, in the view of these observers, the fact that the President has neither called for a ban on privately funded embryo research, nor called upon scientists to desist from research on stem cell lines created after August 9, 2001. They contend that it also makes sense of the requirements, discussed above, that stem cell lines created before that date must, in order to qualify for federal funding, be derived from excess embryos created for reproduction, with donor consent, and without financial inducements.
Those who interpret the policy as reflecting an intermediate or uncertain view of the moral status of human embryos argue further that, if embryonic stem cell research vindicates its promise, there would be no categorical reason to prevent a reconsideration of federal funding in the light of medical advances. A further implication is that people may reasonably draw different conclusions about whether this principle justifies federal funding of stem cell lines derived after August 9, 2001 provided they are derived from embryos left over from IVF procedures, donated with consent, and without financial inducement.⁶⁷ Although the President has declared that he regards destructive embryo research as unethical without additional qualifications,⁶⁸ and although HHS Secretary Tommy Thompson has said that scientific advances would not cause the President to reconsider his policy,⁶⁹ those who interpret the President’s policy as reflecting an intermediate or uncertain view of the embryo argue that the moral logic of this principle admits the possibility that significant medical breakthroughs could justify a reconsideration.

IV. The Moral Standing of HUMAN Embryos

Many elements (though, as we shall make clear, not all elements) of the ongoing debate about federal funding of human embryonic stem cell research seem, as we have reviewed them, to turn on a basic disagreement about the nature, character, and moral standing of human embryos. Public debate over the moral standing and appropriate treatment of human embryos has been quite contentious and divisive in recent years. In part, this had to do with its almost inevitable entanglement with the abortion debate, itself a deep and thorny controversy in America. In part, too, this has been connected to the fact that the question of the moral standing of human embryos touches many other fundamental moral and existential questions involving human origins, human dignity, the moral significance of our biology, and its relation to numerous traditional and widely shared moral teachings.⁷⁰ Differences of opinion on the moral standing of human embryos often suggest differences on these larger questions of overall worldview.⁷¹ Nonetheless, the question of the moral standing of human embryos itself has been taken by nearly all commentators to be amenable to human reason and argument, and a lively debate has raged despite (or perhaps precisely because of) these widely diverging starting assumptions.

In the public arena, the question of the moral standing of human embryos has often been summed up in the question, “When does (a) human life begin?” This question suggests something of the quandary, although the academic and intellectual debate generally takes a somewhat more nuanced question as its starting point. That question has as its unstated premise the fact that under normal circumstances we regard all born human beings (from newborns through adults) as possessing equal moral worth and meriting equal legal protection. It then reflects upon the ways in which human embryos are similar and different from live-born human individuals, the moral significance of those similarities and differences, and therefore whether embryos should or should not be afforded protections.⁷²

The first and most common recourse in seeking an answer to such questions has been human biology, and particularly human embryology. Nearly all participants in the dispute make some reference to biological findings, whether to claim that they teach us about an embryo’s essential continuity with and similarity to human beings at other stages of life, or to argue that they reveal profound and morally meaningful discontinuities between embryos and live-born persons.

While we examine these differing contentions, it is crucial to remember—as several commentators in recent years have noted—that the biological findings, however relevant, are not themselves necessarily decisive morally.⁷³ They may serve better to challenge moral positions founded on erroneous assumptions than to ground some positive moral affirmation or conclusion. For example, a recognition of biological continuity might in some measure undermine the argument that embryo destruction is permissible when certain biological markers or states of development are absent. But it would not by itself show indisputably that embryos are to be treated as simply inviolable.⁷⁴ Meanwhile, recognizing the biological significance of some particular point, marker, characteristic, or capacity would not, in itself, imply some decisive moral significance. A description of early embryonic development is necessary though not sufficient to an understanding of the nature and worth of an early embryo.⁷⁵ It is not sufficient because any purely biological description requires some interpretation of its anthropological and moral significance before it can function as a guide to action.⁷⁶

With these provisions in mind, we offer the following brief review of developments in the debate over the moral standing of human embryos in the past several years.ⁱⁱⁱ

A. Continuity and Discontinuity

Many participants in the debate take the question of the biological continuity or discontinuity between nascent and later human life to be crucially significant. Some argue that the fundamental organismal continuity from the moment of fertilization until natural death means that no lines can be drawn between embryos and adults. Others argue, on the contrary, that some particular point of discontinuity (or the sum of several such points) marks a morally significant distinction between stages, which difference should guide our treatment of human embryos.

1. The Case for Continuity.

Many of those who seek to defend human embryos base their case on some form of the argument for biological continuity and sameness through time. For example, they argue that a human embryo is an organic whole, a living member of the human species in the earliest stage of natural development, and that, given the appropriate environment, it will, by self-directed integral organic functioning, develop progressively to the next more mature stage and become first a human fetus and then a human infant. Every adult human being around us, they argue, is the same individual who, at an earlier stage of life, was a human embryo. We all were then, as we still are now, distinct and complete human organisms, not mere parts of other organisms.⁷⁷

This view holds that only the very beginning of a new (embryonic) life can serve as a reasonable boundary line in according moral worth to a human organism, because it is the moment marked out by nature for the first visible appearance in the world of a new individual. Before fertilization, no new individual exists. After it, sperm and egg cells are gone—subsumed and transformed into a new, third entity capable of its own internally self-directed development. By itself, no sperm or egg has the potential to become an adult, but zygotes by their very nature do.⁷⁸

Many authors therefore regard the activation of the oocyte (by the penetration of the sperm)⁷⁹ or the completion of syngamy (the combining of paternally- and maternally-contributed haploid pro-nuclei to result in a unique diploid nucleus of a developing zygote) as a meaningful marker of the beginning of a new human life worthy of protection.⁸⁰ After this point, there is a new genome, in a new individual organism, and there is a zygote (single-celled embryo) already beginning its first cleavage and embarking on its continuous developmental path toward birth.

All further stages and events in embryological development, they argue, are discrete labels applied to an organism that is persistently itself even as it continuously changes in its dimensions, scope, degree of differentiation, and so on. We can learn names for the various stages as if they were static and discrete, but the living and developing embryo is continuously dynamic.⁸¹ More to the point, in the view of these commentators no discrete point in time or development would seem to give any justification for assuming that the embryo in question was one thing at one point and then suddenly became something different (turning, for example, from non-human to human or from non-person to person). None of the biological events (or “points” in processes), they contend, is sufficient to tell us what we are morally permitted or obligated to do to human embryos, in the absence of one or another additional premises that shape one’s view of these biological events. And if one’s guiding premise is that all human persons possess equal moral standing—regardless of their particular powers, size, or appearance—then there are no grounds for denying the earliest human embryo full moral standing as a person. ⁸²

Some critics of this position argue that it makes too much of mere genetic identity and (uncertain) potential or that it does not make enough of present condition and the significance of development itself.⁸³ There is more to being human, some observers argue, than possessing a human genome or spontaneous cell division, and it matters that the early human embryo is but a ball of cells, without sentience or sensation and without human form.⁸⁴ It matters, too, they argue, that an ex vivo human embryo does not have the potential to develop independently, without further technical intervention.⁸⁵ Indeed, some argue that a human embryo in its earliest stages is essentially no different from any human tissue culture in the laboratory,⁸⁶ or that, because the ex vivo embryo cannot develop if left to itself, it cannot be thought of as truly continuous with more developed human organisms. It may be, in the description of one observer, not much different from a pile of building materials stored in a warehouse.⁸⁷

Nonetheless, advocates of the argument from continuity suggest that it is dangerous to begin to assign moral worth on the basis of the presence or absence of particular capacities and features, and that instead we must recognize each member of our species from his or her earliest days as a human being deserving of dignified treatment. They contend that a human embryo already has the biological potential needed to enable the exercise, at a later stage of development, of certain functions. Sentience and sensation come in later in the process of development, but their seeds are there right from the beginning. And the fact that an embryo cannot develop outside the body is not an argument for leaving it outside the body. There is, they argue, no clear place to draw a line after the earliest formation of the organism, and so there can be no stark division between the moral standing of nascent human life and that of more mature individuals.⁸⁸

2. The Case for Meaningful Discontinuity and Developing Moral Status.

Many other observers, however, argue that some biologically and morally significant discontinuities do in fact present themselves in the course of early human development. These arguments generally do not simply hinge on biological descriptions—which are, in the absence of analysis, largely devoid of obvious moral significance—but instead begin from some implicit or explicit claim regarding the importance of a particular feature, capacity, form, or function (or the progressive accumulation of these) in defining a developing organism as meaningfully a member of the human race.^iv Not simply grounded in biology, they appeal also to a moral or even metaphysical claim about the meaning of humanity.⁸⁹They suggest that the developing human organism might become (at once or progressively) deserving of protection as it becomes able to feel pain, or to exhibit neural activity, or rudimentary features of consciousness, or some elements of the human form, or the capacity to function independently—or as it progressively exhibits more and more of these or other criteria. Until that time, many argue, a developing human deserves some respect because of what it might become, but not protection on par (or nearly so) with that afforded to fully human subjects.⁹⁰ They suggest that genetic identity and organismic continuity are not sufficient; what matters is present form and function, more than mere potential.⁹¹

Several particular putative discontinuities (and combinations of them) have been proposed as candidates for the division between early stages, when a human embryo may be disaggregated for research, and later stages, when it deserves some greater level of protection.

These various particular cases for discontinuity (and these are not the only ones that have been propounded over the years) are not mutually exclusive. Indeed, many of them point to more than one particular element of early human development as finally decisive of moral standing. But they share the belief that moral status accrues only at some later stage of the developing human organism. Their claim, in the broadest terms, is that in its earliest stages a human embryo is not yet simply a human being or a human person, and that it need not be treated as though it were.¹⁰⁴ Human development, they contend, is an essential element in any understanding of human life, and an organism at the earliest stages of that process is not to be treated the same as one much farther along.¹⁰⁵ There are developmental differences, and these differences matter, in ways to be determined by human choice and understanding, as well as by a grasp of the biological facts.¹⁰⁶

Critics of this view contend that while it is certainly true that human beings at different stages of development are not to be treated the same (as children are not given the responsibilities of adults), the crucial treatment here at issue is destructive treatment. No human being, at any stage, they argue, should simply be destroyed for research, and the “use” of an embryo for research, no matter how valuable one deems the research to be, could not amount to treatment of that embryo as “deserving some degree of respect.” The degree of respect granted in destroying the embryo would be zero, they contend.¹⁰⁷

Nonetheless, the case for developing moral status, as articulated by a great number of participants in the policy debates of the past several years, often results in an expression of what has sometimes been termed the “special respect” approach to human embryos: an embryo in its earliest stages is not accorded the full moral standing of a human person, but it is nonetheless regarded as deserving some degree of respect and is treated as more than a mere object or collection of somatic cells in tissue culture. In practice, adherents of this view tend to accept the use of early human embryos in medically valuable research under some circumstances, but they seek to apply some scrutiny to the reasons for which embryos will be used, the circumstances under which those embryos are obtained, and other relevant factors. Several bodies advising the federal government on human embryo research over the years have expressed this view, to varying degrees. The Ethics Advisory Board to the Department of Health, Education and Welfare concluded in 1979 that the early human embryo deserves “profound respect” as a form of developing human life (though not necessarily “the full legal and moral rights attributed to persons”).¹⁰⁸ The NIH Human Embryo Research Panel agreed in 1994 that “the preimplantation human embryo warrants serious moral consideration as a developing form of human life,” though the panel argued that this did not mean that research should be prohibited.¹⁰⁹ In 1999, the National Bioethics Advisory Commission (NBAC) cited broad agreement in society that “human embryos deserve respect as a form of human life,”¹¹⁰ but, like its predecessors, did not recognize the embryo as having the full rights of a human person. The special respect position has been held by its advocates to be consistent with a range of possible particular policies on embryo research, including fairly restrictive ones, and indeed could be held consistent even with an outright restriction on the destruction of human embryos.^{v 111} To consider the embryo “inviolable” (and therefore not a mere utility to be instrumentally used), it is not necessary to presuppose its moral equality with a child, an adult or even a later stage gestating fetus. There may be increasing moral obligations (and natural sentiments) associated with a deepening relationality that extend moral duty without in any way implicitly eroding an imperative of protection at earlier stages of developing life. Most of those who have articulated the special respect position in the public debate have, however, tended to then argue that some research on embryos should be permitted within certain boundaries, even if they have not always agreed on the permissible extent or the appropriate boundaries.

B. Special Cases and Exceptions

Some arguments in favor of permitting and funding embryo research, grounded in the “special respect” approach, do not in fact explicitly (or exclusively) rely on arguments about discontinuity or a biologically grounded view of developing moral status. Instead, or in addition, they rely upon questions of embryo viability and potential, and they are aimed at exploring unique circumstances to address and perhaps resolve questions of the moral standing of certain particular human embryos.

1. IVF “Spares.”

Much of the debate surrounding embryonic stem cell research has focused on the use of cryogenically preserved IVF embryos, left over from assisted reproduction procedures and stored, perhaps indefinitely, in the freezers of IVF clinics. One recent study suggests there are hundreds of thousands of such embryos in the United States alone, though only a very small percentage of them (less than 3 percent, approximately 3,000 or more) has ever been donated for research.¹¹² Although all were produced with reproductive intent and were stored for further reproductive efforts should the first attempt fail, most of these frozen embryos may never be claimed by the original egg and sperm donors for use in assisted reproduction procedures. They are almost certain to remain frozen and, eventually, to die without developing further. Although there have been some efforts to build interest in adopting such embryos, such adoption, some commentators argue, is very unlikely to become a large-scale phenomenon or to affect the fate of most of these stored embryos. ¹¹³ Under the present funding policy, if these frozen embryos were donated for research and embryonic stem cells were derived from them, research on the resulting cells would not be eligible for federal funding. Many observers argue that it should be: Since these particular embryos are almost certainly destined to die without ever developing, it would be appropriate to at least redeem some possible good from their existence and unavoidable demise.¹¹⁴

Some people have pushed the point further. Since the vast majority of the (huge number of) cryopreserved embryos will almost certainly not be adopted, and since many may not be viable even if they were to be transferred to a woman’s uterus, a few observers have argued that, practically speaking, the frozen embryos are virtually all already lost.¹¹⁵ To be sure, they are not already dead, but they are in a so-called “terminal situation” from which no rescue is practically possible. In view of this situation, one commentator proposes extending to these embryos the principle that sometimes, he argues, permits the killing of innocents. That is, killing may be morally permissible in cases where the person will soon die for other unavoidable reasons and where there is another person who can somehow be rescued through or as a result of such a normally impermissible act of killing (thus, as he puts it, “nothing more is lost”). He admits that the case of cryopreserved embryos stretches the application of the “nothing is lost” principle beyond its previous uses, because the embryos in question are alive and at risk of death only because of human choices and designs specifically directed toward them. The principle is also stretched because the lives that might someday be saved through today’s embryo deaths are quite remote. The potential lives saved are those of unspecified future persons with diseases that might be treated by therapies that as yet do not exist and may or may not exist in the future. However, against the weight of all these ifs, which some find formidable, there is the present fact that (like the embryos used to create stem cell lines derived before August 9th of 2001) the cryopreserved embryos are already here, with little or no prospect of rescue—they are, in this observer’s description, already lost.¹¹⁶

Presumably, if destruction of “spare embryos” for human embryonic stem cell research were generally agreed to be permissible through this “nothing is lost” principle, it could be federally funded, subject to such routine secondary considerations as the need for free and informed consent by donors.

Yet this argument, not surprisingly, has met with opposition. Some critics have claimed that it employs circular moral reasoning. The embryos, they argue, are in a “terminal situation” because of human choice and design; thus to then decide that, since they are going to die anyway, they may as well be put to good use is to ignore the moral implications of the original decision to create and freeze them. Critics argue, moreover, that when thinking about our responsibilities to those who are soon to die, we would normally say that it makes a considerable moral difference whether we simply accept their dying or whether we positively embrace it as our aim.¹¹⁷Yet some proponents of using IVF spares argue that the present situation is best understood as a forced choice between two regrettable alternatives for the final disposition of stored embryos (whether donated for research or abandoned). One choice may then be justified as the lesser evil. Even if one deems the original decisions leading to the creation and storage of these embryos questionable, the embryos exist, and the earlier decisions cannot be undone.¹¹⁸

Some have also worried about the possibility of a “slippery slope,” by which the uses of “spare” IVF embryos under this justification might open the door to their wider use in experiments in natural embryogenesis, toxicological studies or chimerizations, or perhaps their development in an artificial (or natural) endometrium,¹¹⁹ (though the reasonableness of “slippery slope” arguments is often disputed).¹²⁰ Other critics point out that the “nothing is lost” principle is not permitted to govern decisions regarding lethal experiments on the terminally ill, on death-row inmates, or even on fetuses slated for abortion.¹²¹

A further issue involves the question of whether accepting the “nothing is lost” principle for already existing embryos condones in principle the use of future excess embryos, or whether the principle actually requires efforts to prevent the creation or storage of “excess” embryos in the future.¹²² Further, this application of the principle relates only to embryos originally created for the purpose of reproduction but not transferred to initiate a pregnancy. Should their use in research be accepted, however, it is not clear that it would be possible to differentiate between embryos created originally for reproduction and extra embryos created with an eye to research uses, since the process of producing them would be identical (though consideration of the extra risks involved for the woman egg donor could act as a counter against any large-scale embryo-creation-for-research).¹²³

Other observers, however, begin from the presence of cryogenically preserved embryos but extend further the argument justifying their use in research. They argue that there is good reason to use embryos for research, not only because a situation some judge tragic already exists but because donating embryos is an act of beneficence and using them is a social obligation incurred by their gift.¹²⁴ This approach would have us start by recognizing that, in the current situation, there is a set of embryos (in IVF clinics) none of which will ever enter a uterus, or even a (still hypothetical) artificial uterus.¹²⁵ These embryos, in one commentator’s term, are “unenabled” and have no potential for full development. Since there is no possible way for such embryos to develop, there is no “possible person” to whom any “unenabled” embryo corresponds; therefore using them in research involves no loss of possible life.¹²⁶

Critics of this approach argue that in effect it allows the moral standing of any given embryo to be decided simply by those responsible for it. Thus, whether a given embryo has moral standing depends only on whether it has a practical prospect of developing, as evidenced by whether it will be transferred to a uterus. But whether it enters a uterus depends on human choices, so the moral standing of a given embryo depends on human choices. If we choose to withhold essential enabling conditions for an embryo’s development, these critics argue, then that embryo will lack not moral standing but merely the opportunity to develop. Its intrinsic nature, including its own potential to develop (given needed conditions), has not changed.¹²⁷

Nonetheless, in the view of a number of commentators, the fact that so many frozen embryos already exist (even if only a small percentage of them are donated for research) changes the balance of duties and respect owed to any single ex vivo embryo. Several observers have argued that the presence of these frozen embryos, with little or no chance of attaining birth, creates special circumstances in which the use of embryos in research (whether destroying them in the course of research or allowing them to die and subsequently using them)¹²⁸ is independent of any final judgment regarding the moral standing or worth of the ordinary human embryo, as such.¹²⁹

2. Natural Embryo Loss.

Some authors tie their moral arguments regarding the use of embryos in research to the fact of the high rate of embryo loss under natural conditions of sexual intercourse and unassisted reproduction. They argue that directed destruction of ex vivo embryos for the purpose of research would not result in greater embryonic loss than occurs in this natural process and would result in far greater benefits for humanity.¹³⁰ The rate of natural embryo loss after conception in unassisted human reproduction (taking in losses both before and after implantation), though not accurately known, is thought to be high, some suggest as high as 80 percent.¹³¹ Moreover, the fact of natural loss is now fairly well known, so that persons who engage in unprotected intercourse, whether seeking to reproduce or not, are knowingly bringing about the conception of many embryos that will die. We generally do not regard this embryo loss as unacceptably tragic, and we do not engage in great efforts to avert it or to find ways to diminish it (beyond research to prevent miscarriage, for instance). For this reason, these commentators argue, using artificially created embryos for purposes of research would not destroy a greater portion of those embryos than ordinarily die in natural unassisted reproduction.¹³²

Moreover, they suggest, the high rate of natural embryo loss should call into question the views of those who believe that early-stage human embryos merit equal treatment with human children and adults. If so many die in the natural course of things, why do we not treat natural procreation as a great fountain of tragedy and carnage? The natural rate of embryo loss, and most people’s failure to mourn its consequences, they suggest, should teach us something about the limited significance of human embryos in the earliest stages. One observer adds that the same logic should diminish our concerns about creating extra human embryos for research, as long as sufficient embryos are created for implantation to keep the chances of survival for any given embryo as good as the chances in natural reproduction.¹³³ Another argues further that human embryonic stem cell research might actually raise the probability of longer survival for all humans, including embryonic ones, and is therefore a case of permissible taking of life, even on the assumption that the embryos are persons.¹³⁴

Opponents of this view, however, have argued that natural deaths of embryos and the deaths caused by intentional efforts to destroy ex vivo embryos for research are not morally equivalent. There are many things that happen naturally that we are not therefore justified in doing deliberately. Indeed, the rate of natural loss of live-born human beings is 100 percent, but that does not justify their killing. And, they argue, even if one were permitted to analogize the deaths of frozen embryos in vitro to the embryonic wastage in vivo, in neither case were the embryos lost destined or created for anything other than their procreative end. In contrast, they argue, using embryos for research bears no relation to their natural direction or trajectory. Critics also argue that the character of our reaction to the natural embryonic death does not justify our practice of destructive embryo research. For they believe that a creature’s moral worth is not dependent on the emotional reaction of others to its death.¹³⁵ The absence of moral sentiment does not imply an absence of moral obligation (nor a right of adverse intervention in a naturally developing human life). Moreover, critics contend, it is not clear how many of these “natural losses” were in fact failures of the fertilization process, so that there was never a unified, integrated organism in the first place, and thus never the loss of a human embryo. It is also unclear, they argue, how much of the supposedly “natural” loss rate is actually due to contingent and changeable factors, such as environmental pollution, pesticides, or endometrial problems, and so is not simply an unavoidable fact of embryonic existence.¹³⁶

3. Prediction of Non-Viability of Embryos.

Some people, hoping to get around the moral dilemma of destroying even “unenabled” embryos, seek to identify a subset of embryos that might reasonably be regarded in advance as non-viable. One proposal has involved the possibility that cloned human embryos, created by somatic cell nuclear transfer, may prove to be non-viable or unable to develop beyond a certain point (biological evidence that this may be the case is presented by Rudolph Jaenisch in Appendix N) or may even, by their nature and origins, simply not constitute the equivalent of human embryos. If this turns out to be true, it is further argued, it might be possible to use them without arousing some of the ethical dilemmas that accompany the use of otherwise potentially viable human embryos.¹³⁷ Others point to a possible sub-group of those embryos currently frozen in storage as potentially non-viable. Although those embryos are not yet dead and, if thawed, would still exhibit some cellular function, some would be unlikely to survive even were transfer attempted. Since IVF procedures usually produce more embryos than can be transferred at one time, goes the argument, the clinicians choose for transfer those among the available embryos that look “the best” and seem most likely to survive and develop—so that those that are frozen are those deemed less likely to develop. Moreover, by applying similar judgment to the unimplanted embryos, we might identify those that would be least likely to survive even under the most favorable circumstances. These embryos might then reasonably be regarded as non-viable and therefore available for research since their use will not disrupt a potential life.¹³⁸

There has not been much direct reaction to this view in the ongoing ethical debates. Yet some observers have noted, in other contexts, that the techniques used to identify which IVF embryos are more or less likely to develop successfully—estimates based usually on visual assessment of the embryos—have never been proven effective or even tested to ascertain their validity.¹³⁹ Moreover, some argue, the true viability of cloned human embryos or of cryogenically stored embryos could not be determined in advance without attempting to implant them.¹⁴⁰

4. Creation of Non-Viable Embryo-Like Artifacts.

Others, seeking to bypass altogether the issue of viability, propose the possibility of creating a biological entity that cannot rightly be called a living organism, yet that has the generic organic powers necessary to produce embryonic stem cells. They suggest that somatic cell nuclear transfer, or a similar technique, could be used to create an entity that lacks, by design, the qualities and capabilities essential to be designated a human life in process. By intentional alteration of the somatic cell nuclear components or the cytoplasm of the oocyte into which they are transferred, researchers may be able to construct an “artifact” that is biologically (and morally) more akin to cells in tissue culture, but could still provide a source of functional human embryonic stem cells.¹⁴¹ Proponents of this innovation aim to shift the ethical debate from the question of whether or when a human embryo should be considered a human being to the question of which organized structures and potentials constitute the minimal criteria for considering an entity to be a human embryo.¹⁴²

Absent all the essential elements (including a full complement of chromosomes, proper genetic sequence and chromatin configuration, and cytoplasmic structures and transcription factors), advocates of this proposal argue, there can be no integrated whole, no organism, and hence no human embryo. By technically constructing biological entities lacking these essential elements yet bearing the partial organic potential often found in failures of fertilization, they suggest it may be possible to procure embryonic stem cells without producing an organismal or embryonic entity that can meaningfully be desi