The Sanctity of Human Life

Chapter 1. ON THE USE OF EMBRYONIC STEM CELLS

C H A P T E R 1 ON THE USE OF EMBRYONIC STEM CELLS NORMATIVE QUESTIONS AND NORMATIVE CONTEXTS The current moral debate about the use of embryonic stem cells for the possible (some advocates might even say probable) saving of other human lives is so intense because—as of 2007—deriving “pluripotent” (useful) stem cells from embryos kills these embryos in the process. This debate takes place in several different contexts: scientific, philosophical, political, and theological. Although complete discussion of an issue such as stem cell research must take all four of these contexts into consideration, one should specify the particular context of any such discussion. Because we are dealing with a moral question that arises out of new scientific research on prenatal life, we should begin our discussion in that context—even though we are approaching this context of the discussion with our ethical commitments already in hand. Hence, ethicists on one side of the debate regarding stem cell research use the scientific differentiation of the stages of prenatal life to bolster their moral differentiation of the stages of prenatal life by attempting to show that their moral differentiation is not arbitrary but has some basis in scientifically established fact. Conversely , ethicists on the other side of the debate deny that this scientific differentiation of the stages of prenatal life has any moral 1 significance and that prenatal life at any stage of its development deserves protection from harm or extinction. Whereas the first group of ethicists uses the specific differences in the stages of prenatal life to bolster their moral argument, the second group of ethicists uses the genetic commonality of all prenatal life to bolster their moral argument.Thus, both sides use scientific evidence to escape charges of arbitrariness in dealing with a moral issue that itself arises out of scientific research. Nevertheless, although science lends itself to moral reasoning, especially in issues that affect its practice, it does not decide what one ought to do with the data and interpretations of data it has provided. Questions of what one ought to do are properly discussed in philosophical, theological, and political contexts. Scientists distinguish between a zygote or preembryo (an egg fertilized by a sperm but not yet implanted into the uterine wall, which usually occurs within ten to fourteen days after fertilization ), an embryo (an egg fertilized by a sperm that has been implanted into the uterine wall), and a fetus (an implanted embryo after about the eighth week of gestation). Because pluripotent stem cells are derived from preembryos that have been kept in a petri dish rather than having been implanted into the uterine wall (as intended in vitro fertilization), in the interest of scientific accuracy one should speak of stem cells being derived from preembryos. To be more precise: Such cells come from young embryos, termed blastocysts, that are only a few days old.1 Some ethicists—Jewish and non-Jewish alike—use this scientific differentiation to assert a moral difference between a zygote and an embryo, arguing that one may treat a preembryo differently from the way one may treat an embryo. Other ethicists argue that there is no such moral difference (although there is a theological difference in certain cases), just as there is no moral difference between the way one may treat an embryo and the way one may treat a fetus.The commonality in kind between a zygote and an embryo— namely, that they both possess the same unique DNA—outweighs any differences in degree between their respective stages of prenatal development. Counting myself among the latter group of ethicists , I use the term “embryo” consistently in discussing stem cell research, for moral reasons and for greater terminological simplic2 On the Use of Embryonic Stem Cells ity. I reserve use of the term “fetus” in addressing the issue of abortion in the usual sense—namely, extraction of a fetus already in utero. Embryos that are used for stem cell research, however, are conceived through in vitro fertilization, which is an extrauterine procedure. For both sides in this intense debate over stem cell research using live embryos, the issue is a matter of life and death. The debate involves three distinct moral questions: May stem cells be derived from live embryos? Should stem cells be derived from live embryos ? Should stem cells not be derived from...