Debates on the moral status of human embryos have been highly and continuously controversial. For many, these controversies have turned into a fruitless scholastical endeavor. However, recent developments and insights in cellular biology have cast further doubt on one of the core points of dissent: the argument from potentiality. In this article we want to show in a nonscholastical way why this argument cannot possibly survive. Getting once more into the intricacies of status debates is a must in our eyes. (...) Not merely intellectual coherence but the standing and self-understanding of current stem cell research might profit from finally taking leave of the argument from potentiality. (shrink)

abstract This paper re‐examines some well‐known and commonly accepted arguments for the non‐individuality of the embryo, due mainly to the work of John Harris. The first concerns the alleged non‐differentiation of the embryoblast from the trophoblast. The second concerns monozygotic twinning and the relevance of the primitive streak. The third concerns the totipotency of the cells of the early embryo. I argue that on a proper analysis of both the empirical facts of embryological development, and the metaphysical importance or otherwise (...) of those facts, all three arguments are found wanting. None of them establishes that the embryo is not an individual human being from the moment of conception. (shrink)

Contemporary philosophical discussion on human embryonic stem cell research has focused primarily on the metaphysical and meta-ethical issues suchresearch raises. Though these discussions are interesting, largely ignored are arguments rooted in the secular research ethics tradition already informing humansubject research. This tradition countenances the notion of vulnerability and that vulnerable human subjects (of which human embryos are likely members)ought to be protected from research-related harms. This is the basic idea behind the argument from vulnerability, and it enjoys prima facie plausibility. (...) This articlepresents the vulnerability argument and then focuses critically on several lines of attack including: (1) twinning and totipotency arguments, (2) embryo-rescuearguments, and (3) natural loss arguments. The article concludes that there is no good defeater for the vulnerability argument, and, therefore, we have undefeated reasons for protecting human embryos from research related harms. (shrink)

Contemporary philosophical discussion on human embryonic stem cell research has focused primarily on the metaphysical and meta-ethical issues suchresearch raises. Though these discussions are interesting, largely ignored are arguments rooted in the secular research ethics tradition already informing humansubject research. This tradition countenances the notion of vulnerability and that vulnerable human subjects (of which human embryos are likely members)ought to be protected from research-related harms. This is the basic idea behind the argument from vulnerability, and it enjoys prima facie plausibility. (...) This articlepresents the vulnerability argument and then focuses critically on several lines of attack including: (1) twinning and totipotency arguments, (2) embryo-rescuearguments, and (3) natural loss arguments. The article concludes that there is no good defeater for the vulnerability argument, and, therefore, we have undefeated reasons for protecting human embryos from research related harms. (shrink)