Take a human ovum, add some sperm, and put the fertilized egg cell in a petri dish. Alternatively, remove the nucleus from the ovum and replace it with the nucleus from a donor's body cell, then chemically stimulate the egg cell to divide.
Either way, after four or five days you've got a blastocyst, a ball of 100 to 200 cells a tenth to a fifth of a millimeter wide. Is it a person?
I think it isn't. You may disagree. But the question cannot be avoided in any serious debate about the ethics of embryonic stem cell research.
Scientists hope these cells, which can develop into all sorts of tissue, can be used to create replacements for damaged body parts, repairing crippling injuries and curing a wide variety of debilitating and life-threatening illnesses. The thing is, they can't get the cells without destroying blastocysts.
If blastocysts are people, destroying them is murder, which cannot be justified by the possibility of medical breakthroughs. If blastocysts are not people, however, the moral imperative is to pursue research that has the potential to save or improve millions of lives.
Scientists are especially interested in blastocysts produced through nuclear transfer (a.k.a. cloning) because they offer the possibility of creating tissue that matches a patient's genes. Such matching would reduce the problem of immune system rejection, making it more likely that the transplant would work.
But the manner in which a blastocyst is produced, whether by fertilization or by cloning, is irrelevant in determining its moral status. Hence the advocates of a ban on research involving human cloning--which the House of Representatives passed last year and the Senate is now considering--are insisting on a distinction without a difference.
"Human 'therapeutic' or 'research' cloning is an experimental tool often confused with, but distinct from, embryonic stem cell research," writes Sen. Bill Frist (R-Tenn.), who opposes the former but supports the latter, in a recent Washington Post op-ed piece. Yet he never explains why the distinction is morally significant.
Frist is troubled by "the purposeful creation and destruction of human embryos in order to experiment on them." It's hard to see why creating embryos specifically for research is worse than using leftover embryos from fertility clinics; wherever they come from, the embryos are still destroyed.
In any case, Frist's objection applies to any stem cell research using embryos created for that purpose. Even if all forms of human cloning are banned, "the purposeful creation and destruction of human embryos" will still be legal.
Urging the Senate to approve the ban, President Bush likewise failed to give a satisfying reason for the focus on cloning. "Research cloning would contradict the most fundamental principle of medical ethics, that no human life should be exploited or extinguished for the benefit of another," he said.
The principle is important, but a lot hinges on how a "human life" is defined. Earlier in the speech, Bush described human cloning as "the laboratory production of individuals who are genetically identical to another human being" (emphasis added), which suggests that he does view a blastocyst as a person.
It's not surprising that Bush did not explicitly address that question, since he cited support for the cloning ban from "those who are pro-choice" as well as "those who are pro-life." But it would be an odd state of affairs if a scientist were prohibited from destroying a microscopic, unimplanted embryo in an attempt to cure Alzheimer's disease while a pregnant woman could legally kill a 3-month-old fetus for any reason at all.
Even stranger, Bush is not trying to protect all blastocysts--only the cloned ones. And he proposes to save them by preventing them from being created in the first place.
Obscuring the issue even further, Bush suggested that "allowing cloning would be taking a significant step toward a society in which human beings are grown for spare body parts." Among other things, that would mean suspending the Constitution, returning to slavery, and abandoning principles accepted by every civilized person. It's not clear why cloning would make this nightmare scenario more likely.
"I am unable to find a compelling justification for allowing human cloning," writes Sen. Frist, revealing a bias against freedom that is all too common in Washington. Some of us are insisting on a compelling justification for closing off this tremendously promising avenue of research. Nobody has offered one yet.