Document Type


Publication Date

Summer 2004


In our brave new world of stem cells, clones, and parthenotes, how should we talk about early human embryos? In fashioning a response to this very thorny question, Ann Kiessling has a core message. It is: (1)that new science produces "new" conceptuses;(2) that science and scientists have failed to differentiate (with appropriate clarity) these new ex vivo conceptuses from those createdin vivo; (3) that new, more appropriate and scientifically-informed, terms are necessary; and (4) that this new language should transform the public discourse about human embryos. No one would deny that the subtleties of human embryology are neglected in public debate. This alone should compel scientists to choose terms that make scientific sense and to provide clear definitions. Dr. Kiessling has accepted well that challenge. But I also think that Kiessling is up to something else in her essay. She is attempting to reposition science, to gain for it a more influential voice in the heated politics of embryonic discourse. It is this point of concern that I shall address.

Invoking the scientific reality of early human development does not, in itself, illuminate the choices to be made about early embryos. Yet good science must challenge policies founded on erroneous assumptions about the nature, character, and moral standing of human embryos. And Kiessling is using good biological evidence to make her case for three terminological choices: For human eggs fertilized with sperm, implantation is "a more accurate requirement for embryo status;" following that definition, nuclear transplants and parthenotes should not be called "embryos." I shall comment on each.



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