Avoiding the potentiality trap: thinking about the moral status of synthetic embryos

  • Monika PiotrowskaEmail author
Original Article


Research ethics committees must sometimes deliberate about objects that do not fit nicely into any existing category. This is currently the case with the “gastruloid,” which is a self-assembling blob of cells that resembles a human embryo. The resemblance makes it tempting to group it with other members of that kind, and thus to ask whether gastruloids really are embryos. But fitting an ambiguous object into an existing category with well-worn pathways in research ethics, like the embryo, is only a temporary fix. The bigger problem is that we no longer know what an embryo is. We haven’t had a non-absurd definition of ‘embryo’ for several decades and without a well-defined comparison class, asking whether gastruloids belong to the morally relevant class of things we call embryos is to ask a question without an answer. What’s the alternative? A better approach needs to avoid what I’ll refer to as “the potentiality trap” and, instead, rely on the emergence of morally salient facts about gastruloids and other synthetic embryos.


Embryo Biotechnology Potentiality Research ethics Stem cell research Synthetic embryo 



Thanks to Gunnar Babcock, Jake Earl, Insoo Hyun, P.D. Magnus and most of all to Matt Mosdell, for helpful discussion and feedback on earlier drafts.


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Copyright information

© Monash University 2019

Authors and Affiliations

  1. 1.SUNY at AlbanyAlbanyUSA

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