Reason and Emotion in the Stem Cell Research Debate

Extracting stem cells from a human blastocyst destroys the blastocyst. Those who defend this (like Michael Sandel) say this is not murder because a blastocyst is not actually human, and therefore to destroy a blastocyst is not killing a human being. A blastocyst is no more a human being than an acorn is an oak tree. (A statement from Sandel can be found here.) Those who oppose this (like Robert George) say that from the moment a human egg is fertilized, a human life exists, and therefore to destroy it is murder. (George's argument can be found here and here. His response to Sandel can be found here.)

Although we agree on the morality of protecting human life against unjustified attack, we disagree about exactly when human life begins, or whether different stages of human life deserve different levels of protection.

There are many conflicting scientific views on the question of when human life begins. According to the metabolic view, the development of human life is a continuous process with no definite point at which human life begins. Even fertilization is not a single event, because after the sperm penetrates the egg, it takes about 24 hours before the chomosomes are combined to form a diploid organism.

According to the genetic view, human life begins at fertilization, because at that point, there is a genetically unique individual that is internally driven by genetic programming to develop into a mature human being if the external conditions (such as implantation in a suitable uterus) are right. This is George's view.

According to the embryological view, human life originates at gastrulation, which beings in the third week of pregnancy, when the embryo is implanted in the uterus, and the cells are differentiated into three primary germ layers--ectoderm, mesoderm, and endoderm--from which the human body will develop. What's significant about this point in development is that from this point twining cannot occur. But during the first two weeks of a pregnancy, it is possible for a zygote to divide into genetically identifical twins. This suggests that there is no single individual identity present, if there is the potentiality for twinning, and thus creating two distinct individuals. (In rare cases, it is even possible for two zygotes to fuse into one zygote with two full sets of chromosomes.)

According to the neurological view, what is distinctive to human life is brain activity. We acknowledge this when we use the standard of "brain death" to define death as the lost of a recognizable cerebral entroencephalogram (EEG). This kind of brain activity is not possible in human development prior to 25 weeks of gestation.

According to the viability view, human life requires self-sustaining viability that does not depend on the mother's uterus, and even with the most advanced medical procedures and equipment, a fetus cannot survive outside the uterus until after 25 weeks of gestation at the earliest.

Good scientific arguments can be made for any of these views of when human life begins. Unfortunately, there is no way to resolve this disagreement by pure reason alone. Because here--as is always the case with moral arguments--we need a combination of reason and emotion, so the the dispute is not just logical but psychological as well. Because we are naturally social animals, and because we feel a natural desire to protect and care for children, we feel a moral emotion of concern for helpless children and indignation against those who would harm children. Leon Kass acknowledges this inescapable emotional element of moral experience when he invokes the moral significance of repugnance and what he calls our "prearticulate human moral sense."

When we argue about the beginnings of human life, we enter a fuzzy borderline where it is hard to see when we are dealing with a human child and when not. In trying to draw a borderline, we can use scientific reasoning to gather and assess the facts of early human development, but deciding what point is crucial is a matter of human emotion. When do we see something that looks enough like a human child to elicit our moral emotion of protection for children?

And yet Robert George takes a rationalistic pro-life position in claiming that this is a purely scientific and rational issue, with no moral emotion involved. He argues that it is simply a scientific fact that "fertilization produces a new and complete, though immature, human organism," and therefore "a human embryo is--already and not merely potentially--a human being." This is so because "the combining of the chomosomes of the spermatozoon and of the oocyte generates what every authority in human embryology identifies as a new and distinct organism."

Against George, some assert that this view contradicts the facts of embryological science, because the possibility of twining during the first 14 days of development shows that there is no single individual human identity until after that point. George responds to this twining argument with an analogy first offered by philosopher Alan Holland. A flatworm cut into two becomes two individual worms, and yet we presumably would agree that the worm was a single individual before it was cut up. Similarly, we should agree that the possibility of a zygote dividing into twins does not deny the fact that the zygote was an individual before the division.

But this is confusing. George says that one possible explanation of twining is that the individual life in the original zygote dies and is replaced by the two individual lives created by the split into two separate zygotes. But George's preferred explanation is that twining is actually a case of asexual reproduction--the original zygote continues to live but it generates a second zygote by splitting.
By the first explanation, one individual must die to produce two totally new individuals. By the second explanation, one individual produces a second individual through asexual budding. This explanation that is preferred by George is strange because it suggests that one twin is actually the parent of the other.

Yet none of this reasoning is sufficient to settle the moral question of how much respect we should give to human zygotes. Deciding whether a zygote is enough like a child to deserve the protection that we would normally give to a child is as much a matter of emotion as it is of reason. As a result of in vitro fertilization procedures, in which far more embryos are produced than are implanted in a womb, hundreds of thousands of embryos have been discarded. Perhaps as many as 400,000 embryos are now frozen in IVF clinics, and most of them will never be implanted. George says that this is mass murder. But even President Bush doesn't agree with this. And in fact, I suspect that most human beings would not agree, because most don't feel the same moral emotional concern for a fertilized egg frozen in an IVF clinic that they feel for a newborn child.

In a statement that can be found here, James Q. Wilson captures this point well. He writes:

"A fertilized cell has some moral worth, but much less than that of an implanted cell, and that has less than that of a fetus, and that less than that of a viable fetus, and that the same as of a newborn infant. My view is that people endow a thing with humanity when it appears, or even begins to appear, human; that is, when it resembles a human creature. The more an embryo resembles a person, the more claims it exerts on our moral feelings. Now this last argument has no religious or metaphysical meaning, but it accords closely, in my view, with how people view one another. It helps us understand why aborting a fetus in the twentieth week is more frightening than doing so in the first, and why so-called partial birth abortions are so widely opposed. And this view helps us to understand why an elderly, comatose person lacking the ability to speak or act has more support from people than a seven-week-old fetus that also lacks the ability to speak or act."

"Human worth grows as humanity becomes more apparent. In general, we are profoundly grieved by the death of a newborn, deeply distressed by the loss of a nearly born infant or a late-month miscarriage, and (for most but not all people) worried but not grieved by the abortion of a seven-week-old fetus. Our humanity, and thus the moral worth we assign to people, never leaves us even if many elements of it are later stripped away by age or disease."

I have written another post on the related issue of abortion.