Few of President Bush’s policies have been as contested as that on stem-cell research. Few have been so poorly understood. At the Democratic convention, many speakers mentioned the issue. But John Kerry and John Edwards have often referred to Bush’s “ban” on stem-cell research, when no such ban exists. Critics charge—and newspapers too often report—that Bush promised federal funding for research on more stem-cell lines than he has delivered. This too is false.

It may be helpful to review the genesis of Bush’s policy. In the 1990s, Congress had repeatedly passed laws banning federal funding for research that destroys human embryos. (I am going to use the word destroys rather than the one opponents of the research would use, kills, because to say kills would be question-begging.) The Clinton administration, toward its end, decided that a way could be found around the law: If researchers took stem cells from human embryos on their own dime, the government could pay for research on the stem cells. As long as the government was not directly funding the derivation of the stem cells—which is what destroys the embryos—funding could proceed. But Clinton did not get around to implementing this policy.

President Bush inherited a no-funding policy and a proposal to allow funding. After several months of public debate on what to do, on August 9, 2001, he announced his decision. In an address to the nation, he said that he would fund research only on stem cells that had been taken from embryos before that date. The federal government would not encourage researchers to destroy more human embryos by providing them with funding. But it would not ban them from doing so either. And it would allow funding to proceed in cases where the embryos had already been destroyed before the policy was announced. It would also provide funding for research on stem cells taken from other sources—from adult somatic cells, from umbilical cord blood, from any source that did not involve the destruction of human embryos.

Eric Cohen, editor of the New Atlantis, describes Bush’s policy as one of “official silence” on the morality of destroying early human embryos: The government neither bans nor funds it. In a related area of research, however, the president has been willing to support a ban. Many researchers are interested in studying diseases by taking stem cells from human embryos that genetically match people who suffer from the diseases. The president wants to block this research altogether by making this process of creating genetically identical embryos—which everyone used to call cloning (critics still do)—illegal.

Bush said that more than 60 stem-cell lines would be eligible for funding under his policy. Critics say that since only 23 lines were receiving funding as of early September 2004, Bush was wrong—or even lied. It is the critics who are mistaken. Bush said that more than 60 lines would be eligible; he did not say that 60 lines would be immediately available for federal funding. The technical process of getting lines ready for research takes time, as does the legal process of assigning rights to them. Neither delay is affected by Bush’s policy. Over time, the number of stem-cell lines has increased, and it can be expected to increase further. (Bush’s opponents have put out the word that the National Institutes of Health has said that only 23 lines would ever be available; this too is untrue.)

Critics of Bush’s restricted funding policy say that it has had a chilling effect on research, for example, by discouraging scientists from going into a field so subject to political change. Most scientists seem to oppose the restrictions on the general principle that science should not be restricted (and that funding should be as generous as possible). But no scientist in the field has said that the policy has prevented him from pursuing any particular research project.

The people you would expect to defend the president’s policy—members of the pro-life movement—have been hesitant to do so. Most pro-lifers had not wanted any funding for embryonic stem-cell research, even a limited amount, and many would be far more comfortable defending a ban on such research than defending a policy that merely declines to make taxpayers fund embryo destruction.

What should we make of the president’s policy? A strict libertarian might approve of the president’s funding restrictions, while also wishing him to cut funding for scientific research in general. For everyone else, the question turns on that vexed subject, the moral status of the human embryo.

There are, to be sure, attempts to sidestep this question. Consider three common arguments for (allowing and funding) the research: (1) Most of it destroys “surplus embryos” from in vitro fertilization clinics that were going to be “discarded” anyway. (2) Real people should not have to suffer in order to protect a bunch of cells. (3) Science must be allowed to progress. Of these arguments, only the second points toward something that is not question-begging. In principle, any restriction on human experimentation can impede the progress of science; nobody considers that a reason not to have any restrictions. Death Row inmates at the end of their appeals are going to die anyway; almost nobody considers that a reason to harvest their organs before their execution. (The promise that it could be done painlessly would not affect anyone’s view of the matter.) The question is whether or not the bunch of cells that make up an early-stage human embryo are persons with moral worth and a right not be killed, just like the bunch of cells that make up you or me—or whether they are something else.

For many people, it is obvious that the embryo is not a person. It has no limbs, no eyes, no awareness. Many times people have said that the embryo “does not look like a human being.” It has fewer human qualities, columnist Michael Kinsley has said, than an insect. But scientists are not interested in stem cells taken from the embryos of another species; it is precisely the fact that they are human that makes these embryos valuable. In any case, the one-celled human embryo looks exactly like a human being—it looks like a human being at that stage of development. Every human being on the face of the earth once looked like that.

Our moral sentiments are an indispensable prop to our moral conduct. Many times, we can see that an injustice is being done without having to think too hard about it. But moral sentiments are not an unfailing guide to justice. Much of the task of a moral education is to train the sentiments to accord with justice. It is very easy for human beings to assume that others who do not “look like us” do not have any rights that we must respect—especially when ignoring their rights offers, or seems to offer, benefits to us. We need to think about the human embryo, not just look at it and conclude it is worthless except as an object of research.

We know that the embryo is alive, not dead or inanimate. We know that it is not just alive the way that one of our skin cells is alive: It is a distinct organism, not a part of some other organism. It has the capacity, under the right circumstances (circumstances that are in an important sense “normal”), to direct its own development from the embryonic to the fetal to the infant stages of development and beyond. And we know that this organism is human and does not belong to some other species.

We do not generally believe that the right of members of the human species to live—that is, not to be killed—depends on their size, age, location, condition of dependence, or number of limbs. Any claim that the embryo does not have a right to be protected from killing has to involve a denial of the idea that “mere” membership in the human species is enough to confer that right. That right will instead have to be posited to depend on some accidental quality that some human organisms have and others do not. Perhaps that quality is sentience or rich relationships with others or an ability to perform high-order mental functions or something else.

But whatever that something is, making the right to life depend on it creates serious problems. First, it is not just embryos who will be denied protection. Newborns can’t perform high-order mental functions either, which is why philosophers who are consistent about denying the importance of membership in the human species, such as Peter Singer, approve of infanticide. Second, these qualities vary continuously. It is impossible to identify a non-arbitrary point at which an entity would have enough of the quality in question not to be killed. Third, for the same reason, it is impossible to explain why some people do not have more or fewer basic rights than other people depending on how much of this quality they possess. The foundation of human equality is denied in principle when we allow some members of the human species to be treated as mere things.

Supporters of embryo-destructive research get a lot of rhetorical mileage out of the idea that embryos cannot be treated exactly the same as a 10-year-old girl. Columnist Ellen Goodman asks who you would save in a burning IVF clinic: the embryos or a child who happened to be there? The implicit analogy is inapposite. Nobody is being asked to take heroic measures to save human embryos; the law is merely being asked to prohibit their deliberate killing. If my cousin were in a burning building with two other people, I might very well save him for a number of reasons. I would not shoot the other two people even if it somehow increased my cousin’s chances of making it out.

Five additional arguments are made for allowing and funding the research.

It is often said that it is foolish to try to protect young embryos when miscarriages happen all the time and nobody tries very hard to prevent them. In many societies, of course, infant mortality rates have been very high, and old people die all the time. That does not make it okay to kill infants or old people.

Second, it is said that a ban, or even a denial of federal funding, will cause research to move to other countries with less stringent ethical norms. But that argument will be available the moment any ethical norm becomes inconvenient. And even if the research did go overseas, the government would at least not commit the injustice of treating the destruction of some human beings in research as acceptable (or, in the case of a denial of funding, commit the further injustice of funding it).

Third, supporters of the research often claim that opposition to it is based on religious dogma that cannot form the basis of public policy. But one does not need to be a religious believer of any kind to see that human embryos are members of the species or to reach the conclusion that human beings should not be killed.

Fourth, there is the argument from disagreement: Why should the government impede, or fail to support, research just because some members of our society object to it? Other people of goodwill support it. But those of us who object to the research do not want the government to deny funding for it because we object; we want it to be denied funding for the same reasons that we object. If our reasoning is correct, then our views deserve to prevail on the merits. A sizable number of people may disagree, but if our reasoning is correct they are simply wrong and should adjust their views accordingly. If our reasoning is faulty, on the other hand, then our conclusion is wrong. The debate can’t be sidestepped by saying that whenever A disagrees with B, we should compromise by going with B’s position.

Finally, there is the argument from Roe. Maybe embryonic life should be protected, goes this argument, but it manifestly is not protected in our society. What is the logic of prohibiting, or failing to promote, potentially life-saving research when abortion is legal in all nine months of pregnancy? There is a possible answer to this question: A person who is pro-choice could nonetheless oppose embryo-destroying research—provided that his view of abortion is based not on the premise that the embryo or fetus is worthless, but rather on the premise that the autonomy and bodily integrity of the pregnant woman somehow trumps its right to life. I would not make this argument myself, but many of the slogans that supporters of legal abortion use accord with it. As a legal matter, the Supreme Court sees abortion in light of a right of women to decide whether to “bear or beget” children, and it has cautioned against defining this and similar (alleged) rights at too high a level of abstraction.

Pro-lifers, meanwhile, may wish that the law protected all human lives from being deliberately taken by others. Realizing that ideal might involve general prohibitions not only on embryo-destructive research but on abortion and some common practices at fertility clinics. To call the obstacles to realizing that agenda substantial is, of course, an understatement. But that is no reason to shrink from insisting on the maximum feasible protection of early-stage human lives from deliberate killing. Destroying those lives for research purposes is something that justice, examined by reason, compels us to resist.

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