From fertilization to approximately the sixteenth day of development, human embryonic cells are said to have the capacities of totipotency and monozygotic twinning, both of which are problematic to a theory of ensoulment at fertilization. In this article I will address the problems which these capacities pose to such a theory and present an interpretation of the biological data which renders ensoulment at fertilization more plausible. I will then argue that not only is an ensoulment theory consistent with current biological (...) data on the human embryo, but it may offer an explanation for the phenomencon of monozygotic twinning. (shrink)

The essential fear from which stems the total ban on human cloning provides a striking evidence for the ultimate importance of whatever is at stake here, such a total ban, as a mere administrative measure, cannot insightfully and effectively counter the technoscientifical thrust that makes possible an ever increasing experimental manipulation of biological phenomena in general and the human body in particular.

To clone humans is deliberately to generate two or more individuals who share the same nuclear deoxyribonucleic acid. Using animals, researchers have performed two basic types of cloning that will eventually yield commercial benefits. Embryo twinning involves separating the individual cells of an embryo and allowing each to cleave for later transfer to a uterus. Cloning by nuclear transfer involves removing the nuclei from embryonic cells or fetal or adult somatic cells and fusing those nuclei with enucleated donor egg cells. (...) Although for the purposes of commercial biotechnology these techniques do not raise undue concern when attempted with animals, embryo twinning, embryo nuclear transfer, fetal somatic cell nuclear transfer, and adult somatic cell nuclear transfer all provoke intense ethical discussions when considered for human use. (shrink)

To clone humans is deliberately to generate two or more individuals who share the same nuclear deoxyribonucleic acid. Using animals, researchers have performed two basic types of cloning that will eventually yield commercial benefits. Embryo twinning involves separating the individual cells of an embryo and allowing each to cleave for later transfer to a uterus. Cloning by nuclear transfer involves removing the nuclei from embryonic cells or fetal or adult somatic cells and fusing those nuclei with enucleated donor egg cells. (...) Although for the purposes of commercial biotechnology these techniques do not raise undue concern when attempted with animals, embryo twinning, embryo nuclear transfer, fetal somatic cell nuclear transfer, and adult somatic cell nuclear transfer all provoke intense ethical discussions when considered for human use. (shrink)

In 1993, investigators from George Washington University Medical Center separated the cells of 17 human embryos and produced 48 embryos, an average of three embryos for each original. The method, variously called twinning, cloning, embryo splitting, and blastomere separation, demonstrated that human embryos could be split to create genetically identical entities during conception. When publicized, however, the experiment brought to mind a different view of cloning repeated since the beginning of the new reproductive technologies. In the early 1970s, when research (...) on in vitro fertilization was in its infancy, commentators worried that cloning–defined as the duplication of persons–would be next, leading to a scenario of “boys genetically exactly like the father, girls like the mother, or individuals like some true or false hero of art, science, or sports, or like some demagogue or some saint.”. (shrink)