It was an arresting photograph: President George W. Bush holding a baby, and surrounded by children, all of whom began life as “excess” embryos otherwise destined for destruction or possibly for use in stem-cell experimentation.

It is hard to imagine a more dramatic demonstration of the fact that human life begins at conception, and that the current debate over embryonic stem-cell research and cloning concerns the most fundamental questions about human dignity and the value of all human life.

At the same time, however, it was (like all photographs) an incomplete and even misleading picture, masking as much as it revealed about the moral complexities of stem-cell research. One was reminded of the similar way in which pictures of the once-robust actor Christopher Reeve, paralyzed in an accident, were used by advocates of stem-cell research. In the Reeve photo-ops, the public was asked to weigh medical treatments and cures for actual suffering persons against the almost abstract consideration that a microscopic embryo deserves to be treated as the moral equivalent of a person. Last month, driven by appeals like those made by Reeve, the Republican-controlled House of Representatives voted to approve funding for embryonic stem-cell research. The research entails the transfer of the DNA of one cell into a human egg-cloning. In extracting stem cells from the newly created embryo, the embryo is destroyed. Bush has vowed to veto the legislation, but the fact that his own party has abandoned him on this issue shows how the imperatives of medical research trump other concerns. Legislators are more willing to support morally dubious and highly speculative medical science than the most basic public-health initiatives. However, like the false hopes raised a decade ago by the attempt to use fetal brain tissue in treating Parkinson’s, there is much hype at work in the current stem-cell debates.

Admittedly, the moral values at stake in embryonic stemcell research are complex. Commonweal has long argued that research that destroys human embryos crosses a dangerous ethical boundary, introducing a fatal utilitarian logic into our decisions about medical treatment. If this sort of human experimentation yields real benefits, it will be nearly impossible to resist extending the practice to use fetuses or the dying as possible sources of cures. If the good to be achieved is great enough, and those involved or their surrogates “consent,” how are we to say no?

At the same time, there is no denying the ambiguous moral status of the early embryo. It is hard to reconcile our ideas about the dignity of every human life with the biological fact that 50 percent of all embryos perish as a matter of course. If nature is so profligate with nascent human life, why must science treat as inviolable embryos that would otherwise be discarded? Moreover, as Karl Rahner asked, if the embryo is a human person, what are we to think of a God who permits half of all human beings to die soon after conception? The moral complexity of life’s beginnings is recognized in Catholic teaching. In the 1987 Instruction on Respect for Human Life in Its Origin and on the Dignity of Procreation, the Congregation for the Doctrine of the Faith (CDF) acknowledged that we do not know if an individual human soul is present from the moment of conception. Nevertheless, because modern science has increasingly revealed the continuity of embryonic development, the evidence strongly suggests that a unique human life, deserving of our respect and protection, is present in the earliest embryo. It follows that we must give the benefit of the doubt to that life, and therefore not purposely destroy it or use it as a means to some other end, rather than as an end in itself.

The CDF’s judgment seems sound, although it is far from conclusive as a guide for public policy. As William A. Galston argued in these pages (“Catholics, Jews & Stem Cells,” May 20), religious traditions disagree about the moral status of the embryo, especially when weighed against the moral obligation to relieve suffering. Meanwhile, stem-cell research is proceeding in the private sector, often funded by state governments. It is not self-evident to most Americans that the potential medical benefits of stem-cell research should be held hostage to the mere presumption that every embryo is endowed with a kind of quasi-personhood.

Finally, it is important to note that research on adult stem cells and on stem cells derived from umbilical cords, neither of which is morally problematic, show great promise. Why have these alternatives not attracted more scientific interest? Is it because the scientific community and the investors banking on future profits from biogenetics are determined to move ahead on cloning? Once cloning for research purposes is accepted, preventing reproductive cloning will be nearly impossible. Reproductive cloning is the first step on the road to the wholesale genetic manipulation of human beings. As the bioethicist Leon Kass has written, “Once cloned human embryos exist in laboratories, the eugenic revolution will have begun.”

The consequences of such a revolution are likely to undermine our very understanding of what it means to be human.

June 7, 2005