We argue in this essay that (1) the embryo is an irredeemably ambiguous entity and its ambiguity casts serious doubt on the arguments claiming its full protection or, at least, its protection against its use as a means fo research, (2) those who claim the embryo should be protected as "one of us" are committed to a position even they do not uphold in their practices, (3) views that defend the protection of the embryo in virtue of its potentiality to (...) become a person fail, and (4) the embryo does not have any rights or interests to be protected. Given that many are willing to treat the embryo as a means in other practices, and that human embryonic stem cell (hESC) research holds the potential to benefit many people, one cannot but conclude that hESC research is permissible and, because of its immense promise for alleviating human even obligatory. (shrink)

It is often argued that certain metaphysical complications surrounding the phenomenon of monozygotic twinning force us to conclude that, prior to the point at which twinning is no longer possible, the zygote or early embryo cannot be considered an individual human organism. In this essay, I argue, on the contrary, that there are in fact several ways of making sense of monozygotic twinning that uphold the humanity of the original zygote, but also that there is no easy answer to what (...) happens when the human zygote twins. All of the options available carry with them one or more surprising, alarming, or otherwise counterintuitive implications. All things considered, I conclude that the “budding option,” according to which the original human organism present before twinning carries on as one of the resulting embryos but not the other, is the most plausible explanation of what happens when a human zygote twins. (shrink)

ABSTRACT In a paper published in Bioethics, Jason Eberl has argued that early embryos are not persons and should not be granted the status possessed by them.1 Eberl bases this position upon the following claims: (1) The early embryo has a passive potentiality for development into a person. (2) The early embryo has not established both ‘unique genetic identity’ and ‘ongoing ontological identity’, which are necessary conditions for ensoulment. (3) The early embryo has a low probability of developing into a (...) more developed embryo. This paper examines these claims. I argue against (1) that a plausible view is that the early embryo has an active potentiality to grow into a more developed embryo. Against (2), I argue that neither ‘unique genetic identity’ nor ‘ongoing ontological identity’ are necessary conditions for ensoulment, and that ‘ongoing ontological identity’ is established between early embryos and more developed embryos. Against (3), I argue that the fact that the early embryo has a low probability of developing into a more developed embryo, if true, does not warrant the conclusion that the early embryo is not a person. If Eberl is right that the human soul is that which organises the activities of a human being and that ensouled humans are persons, embryos are persons from conception. (shrink)

Recent advancements in developmental biology enable the creation of embryo-like structures from human stem cells, which we refer to as human embryo-like structures (hELS). These structures provide promising tools to complement—and perhaps ultimately replace—the use of human embryos in clinical and fundamental research. But what if these hELS—when further improved—also have a claim to moral status? What would that imply for their research use? In this paper, we explore these questions in relation to the traditional answer as to why human (...) embryos should be given greater protection than other (non-)human cells: the so-called Argument from Potential (AfP). According to the AfP, human embryos deserve special moral status because they have the unique potential to develop into persons. While some take the development of hELS to challenge the very foundations of the AfP, the ongoing debate suggests that its dismissal would be premature. Since the AfP is a spectrum of views with different moral implications, it does not need to imply that research with human embryos or hELS that (may) have ‘active’ potential should be completely off-limits. However, the problem with determining active potential in hELS is that this depends on development passing through ‘potentiality switches’ about the precise coordinates of which we are still in the dark. As long as this epistemic uncertainty persists, extending embryo research regulations to research with specific types of hELS would amount to a form of regulative precaution that as such would require further justification. (shrink)