This essay briefly describes a few of the problems associated with using personhood language to defend the right to life of the pre‐implantation embryo. Arguing that an immaterial soul explains the personal identity of an embryo is problematic for many people because there is no apparent spiritual activity in the unborn. While some scholars argue that the embryo has the potential to act as an adult person and thus should be protected from harm, others contend that potentiality alone is insufficient (...) reason to ascribe special moral worth to the embryo in utero. For Thomas Aquinas, the soul is not only the life‐principle that organizes the human body, but it is also that by which the human being thinks and wills. By making suitable corrections to Aristotle's hylomorphic depiction of the soul–body relation, I suggest that a rational soul must be present from the moment of conception and that it is at the service of the person. What is of critical importance here is to accept that a human being is present from the moment of conception, something the vast majority of embryologists maintain, notwithstanding the inveiglement of those who state that the pre‐implantation blastocyst is simply a disorganized clump of cells. (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)

The author seeks to respond to the philosophical appeal of W. Norris Clarke, S.J., “to uncover the personalist dimension lying implicit within the fuller understanding of the very meaning and structure of the metaphysics of being itself, not hitherto explicit in either the metaphysical or personalist traditions themselves.” She does this by discussing the distinctions drawn by Karol Wojtyla: (1) between a human being’s personhood and his humanity, and (2) between the ontological dignity and the ethical dignity of the human (...) person. (shrink)