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Souls, Humans, and God

While we would urge strongly that concerns of justice and beneficence should be weighed as vigorously as concerns about protection of the blastocyst, we recognize that for many people of faith, the status of the developing embryo is a stumbling block. Many Christians would gladly support stem cell work if only they did not associate it with killing. Indeed, the effort to find ways “around” the destruction of the blastocyst suggests that this issue lurks in the minds of scientists, whether Christian or not. Many people, especially people of faith, believe that the zygote possesses a soul. As such they hold that at every stage it must be treated with dignity, as an end in itself, and not sacrificed for some further end, even the end of improved human health.

Official Roman Catholic moral theology exemplifies this belief.See, for instance, Vatican documents such as Donum Vitae (1987) and EvangeliumVitae (1995).This official theology holds that a human being must be respected as a person from “the first moment of conception.” In 1974, Roman Catholic officials stated, “From the time that the ovum is fertilized, a new life is begun which is neither that of the father nor of the mother; it is rather the life of a new human being with his own growth.”From "Declaration on Procured Abortion," quoted in Donum Vitae, 5.I.1.These officials identify three factors that contribute to the constitution of each human being: the egg from the mother, the sperm from the father, and a newly created soul infused by God. The human person here is envisioned as a “unified totality,” both corporeal and spiritual. Roman Catholic officials have noted that from fertilization it is clear that we have the first two factors - the sperm and the egg - but it is not clear whether or not we have the third factor, the God-given soul. To be sure, the presence of the soul is something that human investigation can ever detect. Hence, from the advent of in vitro fertilization, the official Roman Catholic position has relied on a better-safe-then-sorry argument. If we cannot know with certainty when it is that God imparts a soul to the developing zygote, and if we want to avoid all chance of destroying an ensouled human being, then from the “moment of conception” the developing zygote must be treated as if it were a full human person deserving of protection and respect.

In 1987 Roman Catholic officials added to this better-safe-than-sorry argument. Modern genetic science, these officials argued, appears to confirm the belief that the zygote ought to be treated as a human person from fertilization. At fertilization the mother’s DNA combines with the father’s DNA to establish a new genetic code, a code shared with no other human being. From the genetic point of view the zygote is taken to be unique, and thus individual. The officials ask: how can a human individual not be a human person? The zygote is taken to be a “personal presence”; a person with a right to life, a right that cannot be morally denied in medical research. For those who take such a position, it is understandable why the destruction of the blastocyst would be problematic, and why they would be opposed to stem cell research that uses current methods.

However, this argument has problems both scientifically and theologically. Theologically, we should point out that a position that specifically links the possession of a soul to the time of conception has not historically been the stance of the Roman Catholic church. St. Thomas Aquinas, for instance, argued that male embryos were ‘ensouled’ at about 40 days, while female embryos were not ensouled until about 80 days in the womb. If Thomas’ views were accepted in the Church today, there would be no problem with use of the 4-day old blastocyst for scientific research! However, an even more important theological problem, in our view, is that this position, in both its historic form and its current form, sees ‘ensoulment’ as something that God instills into a person at a specific time of development. The soul is seen as a “substance” or “essence” that is infused by God. Our “soul,” then, is something that inheres in us. Whether it is given at conception, or whether it is given or gained at some later time in development, the crucial idea is that it is something that we “have.” Once we have it, we are fully human and should be protected and respected.

There is another theological possibility, however. Our “soul” may not be a statement about something that we possess or that inheres in us. It can be instead a statement about our relationship with God. Many passages in Scripture dramatically demonstrate the care and attention that God has for each one of us, calling us from nonbeing into being and finally into fellowship within the divine life. “The Lord called me before I was born,” says Isaiah; “while I was in my mother’s womb he named me” (Isaiah 49:1). Psalm 139:16 is a powerful statement of God’s knowledge and love for us when we are not yet formed: “Thy eyes beheld my unformed substance; in thy book were written, every one of them, the days that were formed for me, when as yet there were none of them.” What gives the prophet, the psalmist, and the rest of us dignity is God’s call, God’s knowing us and naming us as God’s own. Soul is not a matter of a private, spiritual substance that we possess or that inheres in us or that is added by God to a unique genome. What is decisive is our relationship to God, an eternal relationship God established even before we are formed by calling us toward the divine. However it is imagined, “soul” describes the way in which our life overlaps with God’s life and that we enjoy a spiritual and eternal relationship with God. In this understanding, we might be ‘called’ by God in many ways and for many purposes. Birth need not be the only purpose of our being ‘formed.’

Scientifically, there are also problems with the view that a zygote is a person and therefore should be protected from the moment of conception. First, there is no “moment of conception.” Conception is a process, not an instant. When, exactly, in that process should protectable status be declared? Further, the development of a zygote into an infant goes through many stages. If we respect and protect people differently at different stages of life (for instance, we do not require that children give informed consent for medical treatment, though we do require this for adults), then what kinds of respect and protection are appropriate at these many stages of development in the womb or in vitro?

It is true that conception creates a new entity with a new genome. But it does not create either an individual person or genetic uniqueness. What happens in vivo, naturally within the mother’s body, is this: The zygote can divide into two, four, eight, or more individuals, all with the same genetic code. Identical twins or triplets are one possible result of such a division. Two or three children result who have the same genome. In addition, two eggs can be fertilized after one event of sexual intercourse; and these two zygotes can combine to form a baby with two genetic codes (technically known as a chimera). In fact, some scientists believe that chimerism is very common.

In short, within the first dozen to fourteen days after conception, the early embryo can divide and recombine in various ways. There is no established individual human being until approximately the fourteenth day after conception when the embryo becomes implanted in the uterine wall, a primitive streak appears, and we can identify a single individual who will become a baby if all goes well. If having a ‘soul’ or being a unique human being is a criterion for protection, then that protection would not come into play until about 14 days after conception. The crucial structures that develop at around 14 days help to explain why an informal but widely accepted practice has been adopted by scientists: called the “14 day rule,” it specifies that no embryos are kept developing in vitro beyond 14 days. Ironically, although St. Thomas probably had his science quite wrong when he assigned 40 and 80 days to the developing male and female embryos, he may have understood something important about the need for a delay before assigning ‘ensoulment’ to an embryo.

For both theological and scientific reasons, therefore, we find problematic the stance that assigns absolute value to the zygote and opposes the destruction of the blastocyst in stem cell research. However, we know that Christians of good will may disagree with us. We therefore turn to suggesting some principles that we believe all Christians might affirm.

Email link | Printer-friendly | Feedback | Contributed by: Gaymon Bennett, Karen Lebacqz and Ted Peters

Go to Genetics Topic Index

Souls, Humans, and God

Stem Cell Ethics: A Theological Brief
The Promise and Science of Stem Cells
Stem Cells and Cloning
Framework #1: Protecting the Early Embryo
Framework #2: Protecting Human Nature from Brave New World
Framework #3: Medical Benefits
Jewish and Muslim Frameworks
More Ethical Questions
What about Other Sources of Stem Cells?
What Should We Do?
Further Reading


Gaymon Bennett, Karen Lebacqz and Ted Peters

See also:
Pain and Suffering
Books on Biology, Genetics and Theology
DNA Double-Helix