Ronnie Z. Hawkins, University of Central Florida, Orlando
Research with human embryonic stem cells is so promising for biomedicine that the journal Science hailed recent work as the “Breakthrough of the Year” for 1999. 1 Embryonic stem (ES) cells are undifferentiated cells that can give rise to all three germ layers–ectoderm, mesoderm, and endoderm–which subsequently differentiate into all the tissues of the body. If the proper technology can be developed–and some of the most difficult problems seem to have been overcome already–it may become possible to repair or replace damaged heart muscle, ineffective pancreatic islets, or injured spinal cord and brain cells, among other bodily tissues, with a potential for improving the lives of over 100 million people in this country alone. 2 But the two primary methods of obtaining undifferentiated human cells to date, deriving them from “leftover” embryos created for in vitro fertilization (IVF) and harvesting primordial germ cells from aborted fetuses3, are troubling to many people on religious or ethical grounds. Recently released NIH guidelines, which allow federal funding of stem cell research, subject to certain conditions, only on stem cells that have already been obtained from private sources, have already been criticized by President George W. Bush and will likely be challenged in Congress and in the courts. Representative Jay Dickey (R-AR), for example, has charged that “the guidelines show obvious disregard of the moral conscience and the laws of our nation,”4 and he vows to fight against them.
When human embryonic stem cells are derived from an embryo left over from IVF, the fertilized ovum is allowed to develop for about 5 days, up to the blastocyst stage, comprising around 140 cells. Some of the cells produced, if permitted to continue development inside the womb, would form the placenta, while others, the cells of the “inner cell mass,” would form the embryo. If separated, isolated and then maintained under all the right conditions (which would entail reuniting them in vitro with cells able to form placental tissue and then reinserting the combination into a woman who would carry the embryo through gestation), each of these cells would, theoretically at least, have the potential to form a new human being. It works in the mouse, at any rate.5 Mouse embryonic stem cells (as well as ES cells from other animals) have been produced and maintained in cell culture for some years now, and there have been few ethical concerns raised about them. But a petri dish containing embryonic stem cells from a mouse and one containing cultured human embryonic stem cells (several human ES cell lines are now in existence) will look identical. One would have to distinguish them by testing their DNA– which would still be found to differ by only a small percentage of the total, with virtually every human gene having been found to have a homologous gene in the mouse genome. 6 Why the enormous difference in the way the two culture plates should be regarded, according to some people, supposing they could be distinguished? And why is it that the one offering the most potential benefits to human beings (since mouse tissues and organs would, given our present state of technology, be rapidly rejected by human patients) is the one that they think should be outlawed? I have tried to disentangle a few of the strands of thought behind the no-human-ES- cell-research position, and then to consider what someone with a consistently Darwinian understanding of biology and at the same time a thoroughgoing respect for life might say in reply, in an effort to redraw the moral high ground.
Potentiality
One strand in the thinking of those opposed to embryonic stem cell research, as well as all forms of abortion subsequent to the union of the sperm with the egg, surely the one that gets the most air time, is the issue of interfering with the development of something that has the potential to become, under all the right conditions, a full-fledged human being. If the status of a rights-bearing “person” is attained at conception, the thinking goes, no one should be permitted to interfere with that entity’s right to life, not even the woman in whose womb it must develop for nine long months. The case seems fairly simple and straightforward to those intent on prohibiting abortion, or at least using it as a litmus test for “true believers” at this time in human history (since it has been pointed out that this prohibition did not actually become added to the content of what some accept as “Christian doctrine” until 18797). The issue becomes a little more complicated, however, with our recent advances in technology. When couples seek IVF therapy for infertility, since the procedure is difficult to undergo and technically demanding, with a substantial failure rate for single fertilized eggs, women are often given fertility drugs to allow collection of multiple eggs. Reinsertion of more than one embryo is performed in hopes that at least one will implant and develop to term. Is the woman then obligated to gestate all of the created embryos, perhaps over subsequent pregnancies, since each has the potential to become a human being? When the couple is at risk for genetic diseases, moreover, totipotent cells from the early embryos are removed for DNA testing, a process that will damage these cells irreparably. Are human beings being murdered in the process, even if the remaining cell mass is returned to the womb and allowed to develop normally?
The difficulties multiply rapidly in light of somatic-cell nuclear transfer technology, the “cloning” process that produced Dolly and by now a sizeable menagerie of other animals. If this method were fully perfected, it might become possible to grow replacement human organs with zero risk of rejection, since they could be produced from a cheek epithelial cell, say, taken from the selfsame adult individual in need of a transplant (though research using such technology is, for now, still outlawed under the new guidelines). But this means that, given such technology, any single cell of your body or mine might, under all the right conditions, give rise to a new human life. If it can be done, should it be done? In other words, are we under an obligation to bring all possible “potential people” into existence, if it seems to be within our power to do so? Certain religious traditions do seem to think so–witness the prohibitions on contraception and even onanism, which are at least still given lip service by some. And such an obligation may also recognized for nonreligious reasons: utilitarian philosopher Richard Hare, for example, believes that “there can be duties to merely possible people,” duties which arise in attempting to maximize preference satisfactions without illegitimately restricting a “universal” prescription (in time and place) to merely actual individuals, assuming that those possible people, if brought into existence, would go on to prefer having been so. 8
Hare reasons that another human life on the planet, assuming its experiences on the whole are positive rather than negative, is an additional good, and he subscribes to the utilitarian “total view” that seeks to maximize total, not average, utility. (This is the view which generates Derek Parfit’s “repugnant conclusion,” which Hare finds, allowing for some substantial modifications–the total number of people that we should strive for on the planet, while larger than the present total, would rapidly be limited by the unpleasantness of crowding and resource shortages that would be encountered–not necessarily all that repugnant.) Presumably many of those who fervently decry abortion would agree with him, welcoming as a positive good the million or so extra people that would be born into the United States each year, or the 50 million or so brought onto the planet, were it not for the availability of abortion. 9 Given the fact that world population recently topped six billion, however, this imperative may be a little harder to justify now than it was in the days when Adam and Eve were instructed to “be fruitful and multiply,” even if we’re just talking about joining as many sperm as possible up with as many eggs as possible. In the era of cloning, however, the number of “possible people” has expanded by many orders of magnitude, leading even a “total” utilitarian untempered by Hare’s stipulations, I would hope, to have some second thoughts.
Setting aside theoretical considerations concerning the total possible number of people, however, the attainment of which admittedly few actual people are likely to find desirable, what about the potential of one early human embryo–the particular embryo that you or I, or the white- coated researcher standing next to me, just happen to hold in our hands? When the question becomes immediate and personal, not one of all human embryos in general but of this embryo, specifically, the parallel with the decision facing a woman learning for the first time of an unplanned pregnancy becomes obvious, and acute. When the embryo is in vitro rather than in vivo, relatively more actions than omissions are needed to usher the potential person into actuality, since implantation and gestation in this case require some positive action, not just “letting nature take its course.” The decision stripped bare, however–this one shall live, shall come fully into being, this one shall not–is a frightful one indeed, it must be admitted, one before which it is proper to stand in fear and trembling, I will maintain–as are many similar life- or-death decisions even if they do not specifically concern a human embryo. But it is nevertheless a decision to be made by taking full human responsibility, not by shirking it and declaring the act of deciding itself to be off limits to human beings, in this and in other portentous cases, as I consider in the next section.
Chutzpah
Another strand in the human embryonic stem cell controversy, equally present in the abortion debate, and probably carrying far more emotional weight than the issue of potentiality in the abstract, is the matter of humans “playing God.” Perhaps it is not, in fact, so much a matter of bemoaning the actual loss of “murdered children” from our society that spurs a sizeable proportion of abortion opponents to protest–some would say many of the children we have now often go without the material things and the care they need for a “good” life, without overmuch concern on their part–but rather the idea that some humans have the temerity to stand up and claim for themselves a decision-making power that they believe belongs to God alone. This, as I see it, is at the core of the dispute: there is a fundamental disagreement over the proper nature of the human being. On one view, humans are cast in something of a childlike role, playing at a game of “Father, May I?” It is presumed that, in regard to a fairly large set of decisions, God the Father has given us blanket permission to do as we will with things; decisions about mouse stem cells, for example, or about taking nonhuman life generally, or even about extinguishing entire species from the planet seem to fall into this category and often garner little intelligent scrutiny at all. A certain subset of decisions, however, decisions that deal with whether or not human lives should come into or go out of being, and also to some extent how those human lives should be lived, particularly when it comes to issues of reproduction and sexuality, seems to have been declared out of bounds for human determination. On this view of human nature, humans are meant to be essentially passive creatures submitting to “God’s will,” happily playing with the toys they’ve been given and obediently shunning anything that smacks of forbidden fruit. The really tough decisions are not for humans to make.
An alternative view of the human being makes life a little harder for us. Enmeshed in the marvelous workings of the natural world, and only gradually coming to understand and appreciate their intricacies, the human on this account accepts with a measure of humility a limited place within the scheme of things. But whether or not a God figures prominently in her metaphysics, this human takes responsibility for decisions about life and death in this world– there’s nobody else here to do it. A particular human life may come into being, may develop in a woman’s womb, may grow through childhood and adolescence into maturity–or not, and it is a human decision, rightfully a human decision, perhaps also ecstatically or agonizingly a human decision, either way. Human decision making can intervene, moreover, at any stage of the process: before the egg and the sperm unite, or shortly afterward; before the embryo implants on the uterine wall, or later; indeed, after the infant is born, up until the adult’s final breath is taken. Different beings will be encountered at these different stages, however, from one or a handful of cells to a thinking, feeling, socially complex person, and such different beings call for different considerations on the part of the decision-making agent.
Likewise, different beings are encountered when existence decisions are made about nonhuman life: a monolayer of mouse epithelial cells on a petri plate, a fully developed mouse suffering the pain of a chemically induced liver tumor, an AIDS-infected adult chimpanzee staring out through the bars of his cage. A responsible human being, on this account, cannot claim that “Father” said these beings are all of no consequence. A responsible human being must encounter these different beings as they are, and then make a decision about their fate, if indeed their fate is in her hands. And perhaps a deeper question arises at this point–whose fate is it that most rightfully belongs in human hands, if not precisely the fate of human beings? A jurisdictional issue presents itself: if we have not absolved ourselves of all responsibility by placing such decisions “in God’s hands,” ought we not to have the most authority over ourselves and those of our “own” kind? Could we not say that that which is “self,” or closest to “self,” is that which we are most able to be cognizant of or empathetic with, that which we are most disposed to “do unto” as we would have done to ourselves, and that over which we thereby ought to have the most say so? Deciding, in full responsibility, that some particular life will not continue to exist will never be an easy decision, less so the more “like” the human decision- making agent it is. The more we make such decisions with the full gravity of the situation in view, the more likely, I would think, we are to treat that life with the “respect” it is due.
Respect
Life is hard for the secular bioethicist who gets appointed to a seriously political policy- recommending body like the NIH’s Human Embryo Research Panel or the National Bioethics Advisory Commission, which recently sketched out what became the new rules for stem cell research; in this pluralistic society, whatever you recommend will never make everybody happy, and in the attempt to reach some sort of collective agreement, little coherence is likely to be manifest in the final position. The Human Embryo Research Panel, charged in 1994 with providing advice on federal funding of work on “the ex utero preimplantation human embryo,” finally came up with the view that such an embryo is not quite yet an entity with interests or rights, but still one that “deserves special respect” and “serious moral consideration.” 10 But what, exactly, does that mean, when a researcher is faced with a cell culture in a petri dish? At least one who marks a human “right to life” beginning at the moment of conception has a working definition of “respect”: certain things you just do not do. But once you’ve admitted the cells into your lab–should there be two different biohazard bags provided for the disposal of used material, one marked “handle with respect” for the human stem cell cultures and one left unmarked for the mouse cell lines? And then, pray tell, how would you carry out the different injunctions?
Even without a religious orientation, we can recognize an urgent need to maintain that living human tissues should be “respected” in some way, since we face seemingly irresistible forces in the opposite direction–market forces. The U.S. Patents and Trademark Office has been issuing patents on living things, or elements thereof, from genetically engineered organisms to human gene sequences, ever since the landmark Supreme Court decision on Diamond v. Chakrabarty in 1980. 11 Then there is the famous case of John Moore, a patient at UCLA’s School of Medicine being treated for hairy cell leukemia in the late 1970s. His spleen was removed in the course of treatment, along with repeated samples of blood and bone marrow; certain chemicals derived from these tissues were patented, apparently without Moore’s knowledge or consent; and Sandoz reportedly paid $15 million for rights to develop “the Mo cell line.” 12 Moore brought suit against his doctors at UCLA when he found out about it in 1984, declaring “I was harvested.” Many were amazed, however, when the court sided with UCLA, not wanting to threaten “the promise of biotechnology innovation.” 13 Neither embryo-derived nor pluripotential, the Mo cells don’t seem to have attracted protestors on the streets speaking out for their rights, but the incident and its legal outcome should raise a host of ethical questions. What is this “respect” that we hear about on occasion? What might a policy of “respect” consist of, and what would a coherent foundation for one be?
Revaluing Life–And Not Just Human Life . . .
The biomedical research community finds itself embattled today on a number of fronts, and like the secular bioethicist has problems with consistency and coherence. Science’s lead editorial on the new stem cell rules, for example, ends on a combative note that recognizes a difference of worldview underlying a number of debates: “The forces that have placed stem cell research in peril are powerful, and they are among a number of voices challenging science, whether the issue is research on embryos, reproductive biology, or the teaching of evolution in the schools.”14 Evolutionary theory, as a grand unifying theme within contemporary biology, is key to one of these worldviews, all right; but working through all of its implications is something that many of us, biomedical scientists, secular bioethicists, and the scientifically enlightened general public, have heretofore shied away from. Perhaps its most central tenet is that of evolutionary continuity. As the co-decipherer of the human genome, Craig Venter, remarked on the day completion of the first draft was announced, “[o]ne of the wonderful discoveries that my colleagues and I have made while decoding the DNA of over two dozen species, from viruses to bacteria to plants to insects and now human beings, is that we are all connected to the commonality of the genetic code and evolution.”15 But if we fully integrate this main insight of modern science, evolutionary continuity, we will need to rethink one of the fundamental ontological commitments that most of us in western culture, religious and secular alike, hold dear: that there is a great gulf existing between human life and all other life, a difference not just of degree but of kind, on which we may found the profound difference in our valuation of such lives. One can, of course, hold to a certain ontology through a “leap of faith” that spurns all empirical evidence, but only at great cost to any hope of coherence between the physical and the metaphysical.
If we do recognize and respond to evolutionary continuity, however, it may prove somewhat inconvenient to our comfortable lifestyles. Realizing that farm animals have well- developed vertebrate nervous systems not unlike our own means, for example, that, yes, they probably are suffering on the factory farm, as are the hundreds of thousands of rats and mice who receive no pain medication for their intentionally induced malignancies. Interestingly, in June of 2000, Nature Neuroscience took note of Steven Wise’s recent book, Rattling the Cage, in an editorial addressing animal experimentation. Wise, an attorney arguing that at least some nonhuman animals–the great apes, in particular–should be given legal rights, since there is now a tremendous weight of evidence attesting to their higher cognitive capacities, which he mobilizes effectively in making his case. The editors observe that “[t]he traditional view is that there is an absolute distinction between humans and all other animals, but Wise argues that modern biology has made this obsolete, and that there is no reason why it should remain embodied in law,” and they admit that “[i]t would be unproductive to deny that the arguments raised in Wise’s book have some force.” 16 They advise, however, that biomedical researchers “will need to refute [the book’s] arguments” if they hope to stand up to the coming legal challenge.
Certainly, if the laws change, there will be adjustments to be made on the part of researchers. However, I think a little reflection on adopting a position of greater consistency within bioethical thought about all the issues I have raised here could prove immensely valuable. Yes, there is often not a great deal of respect shown to nonhuman animals or their tissues in research labs: unless things have changed quite a bit, for example, rats and mice are probably still killed, in many cases, by swinging them by their tails and hitting their heads into the lab bench. We don’t want the treatment of human beings to go there, nor are we comfortable with the prospects of our organs and tissues being reduced to commodities on the open market. But, if we were to acknowledge the truth of evolutionary continuity, why should the slide be in that direction? In other words, why not revalue all life, and take responsibility for treating it all with “respect”? What would some of the implications of such a change in attitude be?
Should we begin to truly respect all life on the planet, first of all, an imperative to bring more and more human lives, and only human lives, into being would become very difficult to support. If we update our ethics with our current science, an ecological understanding makes it clear that, within any ecosystem, there need to be organisms of different types, in proportions that can be specified within broad limits, in order for their needs to be complementary and the system itself to be optimally functional. In many places, human numbers have probably already exceeded those limits, to the detriment of other life, if not their own. If all life is valued, how might we respond? Though this is easier said than done, one option is for all of us to decide to reduce our human family sizes steadily over the coming decades; religious and cultural commitments aside, this course of action would seem to be as prudent for us as it is ethical.
Would there still be animal experimentation? Well, improving the quality of lives–all lives–would certainly not cease to be a worthy goal if the valuation of life were strengthened and expanded. We are fortunate that, at this time in our history, if we choose the path of experimenting with human cells and tissues maintained in laboratories, combined with the willingness of individual human volunteers to further our collective knowledge, we have the means to learn just about everything we could wish to know without further coercion and exploitation of nonhuman animals. Invasive and destructive neurological research on nonhuman primates? There’s not much it could tell us now that wouldn’t be discoverable utilizing noninvasive techniques on consenting human subjects, though this may not have been the case twenty or thirty years ago. With some notable historical (and perhaps current) exceptions, the principle of informed consent lies at the heart of human experimentation, as outlined by the Nuremberg Code. But nonhuman animals cannot give “informed consent.” Are there any conditions under which we might reasonably, as guardians, impute such consent? Possibly; certainly if a proposed experiment offered a hope of improving a disability the animals themselves suffered from, as we consider permissible for the inclusion of young children in experimental medical procedures today. And, given present social conditions, it might not be unreasonable to suggest that dogs and cats that would otherwise be euthanized instead be employed for, say, teaching veterinary students spaying and neutering techniques or other therapies, if in repayment for their “volunteering” they were given to loving homes–something that in fact was prohibited in many vet schools just a few years ago, when vet students and others who offered to take home their experimental animals were forced, instead, to terminate them at the end of the experiment.
Lurking in the background of such a draconian rule, as well as more generally in biomedical research, is, I think, a notion that many researchers are presently unwilling to give up–the notion of disposable life, a holdover from the “Father told me it doesn’t count” view of nonhuman life. If vet students, med students, and other interested parties took home their experimental surgery dogs and made them into pets, they could no longer be considered “disposable,” and suddenly a slip of the scalpel would matter more, as would a kind word or deed–considerations that might reasonably be expected to accompany an attitude of “respect.” In my time, out of concern for the undue burden this attitude might impose on professional students, whole courses were devoted to “desensitizing” them, making them less distractible by the pains and privations of those in their care, animal or human. Times have changed in this regard, and I think we should all be glad they have. But an essential part of the change should be a questioning of the fundamental assumption, made not only in the research lab but far and wide around the world, that in order to treat one form of life well, another must be treated badly by contrast. What, indeed, do we express in linguistic constructions such as “we were treated like animals,” unless there is widespread agreement that harsh, injurious, and disrespectful treatment is appropriate for animals, and that one way to distinguish people is by their not being treated in such a fashion? Who set up such a rule–is it given in the Ten Commandments, if you embrace them, or implicit in secular ethics, if you do not?
To return to human embryonic stem cells, an interesting defense is given, by one bioethicist, of the mandate to show “respect” to the human embryo and its derivatives. The author speaks of “the fundamental wonder of life itself: the journey of an organism of microscopic size through various patterns and processes of development,” a veritable “mystery” of life; he goes on, then, to speak of the development of “a flourishing human person.” 17 But all multicellular living things undergo a pretty miraculous transformation in developing into what they eventually become, and we are far from unraveling, let alone understanding, all the processes involved in this “mystery.” Why, then, is the human course of development the only one worthy of respect? I think that a consistent Darwinian position on this question would answer that it is not. There is no wide ontological chasm, at least not one underwritten by any scientific evidence, distinguishing a petri dish bearing human embryonic stem cells from one containing mouse stem cells, nor is there much of one, fundamentally, between the ways the cells from each dish might develop. There are differences in the characteristics of the adult animals, but also far more commonality than we have been given to appreciate, and this is something that we should now be able to acknowledge without a threat to our self-esteem. But to move on beyond this point we need to have the courage to stop playing a game of “Father May I?” as a way to avoid taking responsibility for the tough decisions we must make about matters of life and death, be that life human or nonhuman.
Works Cited
Campbell, Courtney S. “Awe Diminished.” Hastings Center Report25 (1995): 44-46.
“Capturing the Promise of Youth,” editorial, Science286 (1999): 2238-9.
Hare, R. M. “Possible People.” Bioethics2 (1988): 279-93.
Hawkins, Ronnie Z. “Reproductive Choices: The Ecological Dimension.” Contemporary Moral Problems. Ed. James E. White. Belmont, CA: Wadsworth, 2000. 186-198.
Jacobson, Jodi L. The Global Politics of Abortion. Worldwatch Paper 97. Washington DC: Worldwatch Institute, 1990.
Kennedy, Donald. “Two Cheers for New Stem Cell Rules.” Science289 (2000): 1469.
“Legal Challenges to Animal Experimentation,” editorial, Nature Neuroscience3 (2000): 523.
Nelkin, Dorothy and Lori Andrews. “Homo Economicus: Commericalization of Body Tissue in the Age of Biotechnology.” Hastings Center Report28 (1998): 30-39.
O’Brien, Stephen J., et. al. “The Promise of Comparative Genomics in Mammals.” Science286 (1999): 458-80.
Parens, Eric. “What Research? Which Embryos?” Hastings Center Report25 (1995): 36.
Pence, Gregory. Who’s Afraid of Human Cloning? Lanham, MD: Rowman and Littlefield,
Perry, Daniel. “Patients’ Voices: The Powerful Sound in the Stem Cell Debate.” Science287 (2000): 1423.
Population Crisis Committee. Access to Birth Control: A World Assessment. Population Briefing Paper No. 19 (October 1987).
Robertson, John A. “Symbolic Issues in Embryo Research.” Hastings Center Report25 (1995): 37-38.
Vogel, Gretchen. “Researchers Get Green Light for Work on Stem Cells.” Science289 (2000): 1442-3.
Wright, Shirley. “Human Embryonic Stem-Cell Research: Science and Ethics.” American Scientist 87 (1999): 352-61.
- News and Editorial staffs, “Capturing the Promise of Youth,” Science286 (1999): 2238-9.
- Daniel Perry, “Patients’ Voices: The Powerful Sound in the Stem Cell Debate,” Science287 (2000): 1423.
- The research teams of Roger Pedersen at UCSF and James Thomson at the University of Wisconsin are working with IVF-derived embryos; John Gearhart’s team at Johns Hopkins is working with primordial germ cells. See Shirley J. Wright, “Human Embryonic Stem-Cell Research: Science and Ethics,” American Scientist87 (1999): 352-61.
- See Donald Kennedy, “Two Cheers for New Stem Cell Rules,” Science 289 (2000): 1469, and Gretchen Vogel, “Researchers Get Green Light for Work on Stem Cells,” Science289: (2000): 1442-3, 1442.
- See Wright, 354.
- See Stephen J. O’Brien et al., “The Promise of Comparative Genomics in Mammals,” Science286 (1999): 458-80, 460.
- As reported by Gregory Pence, Who’s Afraid of Human Cloning (Lanham, MD: Rowman and Littlefield, 1998), 88.
- R. M. Hare, “Possible People,” Bioethics2 (1988): 279-93, 284.
- These very round estimates were taken from my “Reproductive Choices: The Ecological Dimension,” as reprinted in Contemporary Moral Problems, sixth edition, ed. James E. White (Belmont, CA: Wadsworth, 2000). For original figures, see Population Crisis Committee, Access to Birth Control: A World Assessment, Population Briefing Paper No. 19 (October 1987), as reported in brief for Population-Environment Balance, et al., as Amici Curiae supporting appellees in Webster v. Reproductive Health Services, Supreme Court of the United States, October term, 1988, and Jodi L. Jacobson, The Global Politics of Abortion, Worldwatch Paper 97 (Washington, DC: Worldwatch Institute, 1990).
- See Eric Parens, “What Research? Which Embryos?” Hastings CenterReport 25 (1995): 36, and John A. Robertson, “Symbolic Issues in Embryo Research,” Hastings Center Report25 (1995): 37-38.
- A microbiologist, Ananda Chakrabarty, was awarded a patent on a genetically engineered microorganism designed to clean up oil spills by ingesting and breaking down the petroleum, the first patent to be issued on a living organism.
- See Dorothy Nelkin and Lori Andrews, “Homo economicus: Commercialization of Body Tissue in the Age of Biotechnology,” Hastings Center Report28 (1998): 30-39, 32.
- Ibid.
- Kennedy, 1469.
- Excerpt from news conference at the White House on June 26, 2000; New York Times27 June 2000, D8.
- Editorial staff, “Legal Challenges to Animal Experimentation,” Nature Neuroscience3 (2000): 523.
- Courtney S. Campbell, “Awe Diminished,” Hastings Center Report25 (1995): 44-46, 44.