The Facts of When Human Life Begins

Interview With Maureen Condic of the Westchester Institute

By Karna Swanson

The conclusion of scientist Maureen Condic that human life begins at a defined moment of conception isn’t an opinion based on a belief, but rather a “reflection of the way the world is.”

Condic, a senior fellow of the Westchester Institute for Ethics and the Human Person, published her conclusions in a white paper titled “When Does Human Life Begin?” In the report she addresses the topic using current scientific data in human embryology.

An associate professor of neurobiology and anatomy at the University of Utah School of Medicine, Condic received her doctorate in neurobiology from the University of California, Berkeley. Her teaching focuses primarily on embryonic development, and she directs the University of Utah School of Medicine’s course in human embryology.

In the interview with ZENIT, Condic explains why the question of when human life begins is important to address, and what scientific criteria she used to define a “moment of conception.”

Read the rest here

I like these bits especially:

"To address this question scientifically, we need to rely on sound scientific argument and on the factual evidence. Scientists make distinctions between different cell types (for example, sperm, egg and the cell they produce at fertilization) based on two simple criteria: Cells are known to be different because they are made of different components and because they behave in distinct ways.

These two criteria are used throughout the scientific enterprise to distinguish one cell type from another, and they are the basis of all scientific (as opposed to arbitrary, faith-based or political) distinctions. I have applied these two criteria to the scientific data concerning fertilization, and they are the basis for the conclusion that a new human organism comes into existence at the moment of sperm-egg fusion."


"However, a scientific analysis of the best available data does not support the conclusion that fertilization is a “process”; it supports the conclusion that fertilization is an event that takes less than a second to complete.

The events of the first 24 hours following sperm-egg fusion are clearly unique, but they are also clearly acts of a human organism, not acts of a mere human cell."

I think it pretty much confirms on a factual level that a human life commences at an immediate point in time (at conception). The result is that those so-called pro-choice people are indeed advocating murder of human life through abortion.

Pro-abortionists have lost the debate on when life begins; this is no longer an issue which scientists even debate. Life, unambiguously, begins at conception.

The debate is over something called personhood, with the claim made that an embryo is not a person. Since personhood is not a scientific term its meaning becomes whatever someone wants it to mean and it becomes an argument over something that sounds real but isn’t.


IMO, human life begins at implantation (or after implanation is complete). It does not begin at fertilization. This accords with the current medical science definition of pregnancy as beginning with implantation, not fertilization.

In my view both scientists and theologians who either in ignorance (IMO) or out of convenience piggyback on the scientists view of DNA formation being constitutive of the formation of human life are wrong.

Theology is not beholden to science and there’s intense debate in science on many biological issues (ex. definition of a species – this relates btw to how things like Endagered Species acts are implemented … there are literally dozens of different definitions of species that have been proposed by scientists).

Here’s the fundamental problem and we need to separate this issue from the desires we have about abortion.

The argument is that at fertilization (or completion of fertilization), that someone with a unique DNA is formed and thus a new human individual life exists. The problem is that up and till recently it was assumed that identical twins had identical DNA (we now know believe it or not that that’s not quite true) yet no one saw any inconsistency. Also human clones may end up having exactly identical DNA – that doesn’t mean the clone is not a unique individual. Whether someone is a unique or unique new individual is not determined by whether a unique set of DNA has been formed. We also are discovering more and more now that the DNA of an individual is not actually static. And actually parts of your body will include cells with DNA slightly different than other parts of your body. So this whole materialistic (and frankly idiotic) notion of DNA being constitutive of human identity is in my view entirely discredited. I don’t know who thought of this idea but whoever it was, be it theologian or scientist, is just wrong.

Let’s suppose that someone had malformed DNA as some people do. Let’s suppose that in the future we are able to develop technology that replaces this malformed DNA in a grown individual with artificial substitutes with the DNA somehow excreted from the system. That person wouldn’t then suddenly not be human. Maybe according to some whacky biological definition he wouldn’t be, but theologically he would still be human with a human body and human soul.

With those errors out of the way, let me now make my own positive case for my earlier stated view.

It seems to me that the formation of a new human life in a woman involves naturally two things:

Union of sperm and egg in intercourse.
Union of embryo with the mother in the womb (i.e. after implantation is complete).

The first of these involves the union of man and woman. The second, of child and mother. In pregnancy, not only is it preceded by a union of man and woman made fruitful (the seed of life which is the unimplanted zygote) but it is effected by the union between the body of a new human life with the mother (the completion of implantation). One cannot separate these two elements.

So that’s when human life begins. When human personhood begins is another question and I would put that at human brain emergence. So an implanted embryo (or blastocyst) that is yet to develop a brain would be life, the nascent human life that at brain emergence becomes an actual human person with a rational soul. IMO, it is contrary to Catholic doctrine to suppose that a rational soul exists prior to the existence of the brain. This is b/c it is IIRC a dogma that the soul is the form of the body in a way such that the presence and union of soul in body is realized in that same body – IOW, the rational soul can’t be present in a body in some detached way, it must be present in the body itself. But without a brain, it is difficult to see how that could be true. The only way for rational soul at zygote formation to be consistent with Catholic dogma and doctrine is IMO to say that the zygote somehow exhibits in a way unbeknownst to us intellectual activity or at least intellectual potentiality – this isn’t the potential for intellectual potentiality that would need to be there but actual intellectual potentiality (which is present in some in a PVS situation for example but supposedly not in some in a brain death situation). Unless there’s something mysterious about the human zygote beyond current scientific knowledge and which is not present in animal zygotes, this seems clear cut. I think I wasn’t quite clear on the Catholic dogma I referred to there. The Catholic dogma there as I understand it, entails that it is heretical to suppose that a body without a rational soul is indistinguishable in principle from a body with a rational soul. It entails that the presence of the rational soul must be in principle visible in the body, in the actual body itself of which it is the form. I think this complicated issue is why the church and Pope Benedict XVI then CDF Prefect notes:

Certainly no experimental datum can be in itself sufficient to bring us to the recognition of a spiritual soul; nevertheless, the conclusions of science regarding the human embryo provide a valuable indication for discerning by the use of reason a personal presence at the moment of this first appearance of a human life: how could a human individual not be a human person? The Magisterium has not expressly committed itself to an affirmation of a philosophical nature, but it constantly reaffirms the moral condemnation of any kind of procured abortion.

So prescinding from an affirmation of philosophical nature, the church teaches that abortion is regardless what may ultimately be the case there, is to be morally condemned.


One words. Nuts.

Your entire argument collapses when one considers that it is a mere technological obstacle to incubate an embryo to full term in an artificial environment. By your definition, that child could come to term, be removed from the synthetic ‘womb’, raised, educated and participate in society, but NEVER become a “person.” Because he never implanted in a mother.


Fertilization is where there is a change in very essence, not implantation.

As for identical twins, God is the one who creates persons, so he alone knows if the fertilization has resulted in one or multiple new human beings until the split is observeable.

As for cloning, first of all it hasn’t happened yet. It may not be technically possible, but for sake of argument let’s say it is. The way this is done is by inserting the DNA to be cloned into an egg stripped of its own DNA. The recipient egg environment stimulates the donor DNA into begining the development cycle from there. In other words, conception is artificially induced.

The argument is not that the uniqueness of the DNA proves it is a separate human. It is that the unique DNA resulting from conception proves it is NOT merely part of the woman’s body like some claim. The DNA argument is that the DNA is behaving in that unqiue manner that is triggered only at conception. Never again in the life cycle of the human person does it behave like it does at conception - that moment is utterly unique for a reason.

Sorry, I don’t buy your rationalizing. Let me guess, you support IVF and stem cell research… Theology is NOT beholden to science as you say. But when science accurately describes reality, it DOES end up being consistent with theology. Catholicism has always noted the inherent compatibility and complementarity of science and theology.

I don’t understand… Are you saying that the fertilized egg is inhuman until it implants or that there is no life in a fertilized egg until it implants. So when a fertilized egg implants it becomes human and alive?

not quite. You make a good point here, but my view accounts for that. My view is that in that hypothetical situation (which IMO is further into the future than human cloning is since for one thing human cloning has actually already happened), human life indeed would not exist at the same developmental stage it would for the natural case of fertilization and implantation. In that hypothetical, a new human individual life would come into being at the same instant as a new human person comes into being (i.e. human brain emergence). Also in that case, there would be no pregnancy. It is not the developmental stage which grounds that implantation is the occasion for a new human life but rather that organism’s being united in pregnancy after implantation that does so. There’s no disputing that the zygote is life, the question is, is it theologically speaking human life. When implantation is complete, the entity is human life due to the pregnancy despite the absence of a rational soul. In your hypothetical the eventual presence of a rational soul would ground the entity being human life. However, in your hypothetical as well as in some others that are more realistic, there are questions left unanswered such as – would that person, though human, be theologically a descendent of Adam and Eve (whether they were a couple or an evolving group)? But that’s another topic.

Even an unfertilized egg is life, the question is what kind of life is it theologically (or philosophically) speaking. That’s the ontological reality that is of ultimate concern to the church (and should be for us), not what taxonomy or conceptual scheme contemporary biologists use. Contemporary scientists don’t make any distinction ontologically between humans and other animals, but we know that a gulf exists there regardless of what scientists may say about chimp DNA versus human DNA and evolutionary pathways.

See my previous post for more details. But the bulleted points would be

  1. At fertilization’s completion it is life and is an organism and it has a vegetative soul (Aquinas discusses three kinds of souls – plant or vegetative; animal or locomotive or sensitive; and rational soul; so souls are present in animals and plants too … pop culture and theology differ there).

  2. At implantation’s completion it is properly speaking a human life due to the pregnant union with the mother – NOT due to a developmental stage, but due to the theologically significant union with the mother, which Aquinas expounds upon by for example, even saying right up til birth (not ensoulment, but birth) a single guardian angel guards both mother and child due to the intimate connection between the two.

  3. At some point in the stage of development it will gain a sensitive soul (aka “animal soul”). It is still not a human person with a rational soul. this doesn’t necessarily mean however that at this point or at point (2) that it shouldn’t be accorded the kind of respect and care one might accord a human person.

  4. Then at some point in the stage of development, it will gain a rational soul. At this point then it is a human person. Person in Catholic theology means a “hypostasis” with a rational nature. This can be an angel (which has a rational nature, but no rational soul) or God or a human person. Legally, the definition may be different. It’s not always clear to me when the church does not specify it which definition they are working under sometimes.

Abortion outside of extraordinary cases is seriously or venial sinful at at point 2 as well as with increasing seriousness 3 and 4.

This is wholly inaccurate. Embryology is clear, life begins at conception.

"Human development begins after the union of male and female gametes or germ cells during a process known as fertilization (conception).
“Fertilization is a sequence of events that begins with the contact of a sperm (spermatozoon) with a secondary oocyte (ovum) and ends with the fusion of their pronuclei (the haploid nuclei of the sperm and ovum) and the mingling of their chromosomes to form a new cell. This fertilized ovum, known as a zygote, is a large diploid cell that is the beginning, or primordium, of a human being.”
[Moore, Keith L. Essentials of Human Embryology. Toronto: B.C. Decker Inc, 1988, p.2]

I frankly don’t know enough and haven’t prayerfully studied and reflected and prayed enough to be able to say with any certainty anything about IVF especially. My inclination though is to say that IVF is not morally ideal. So even if IVF were just as safe and healthy as the natural method, I would not view it as morally wise for a couple for some odd reason to elect to conceive by that method when they are able to conceive by the natural method. In the real world cases, I don’t have any opinion besides what I’ve stated. I once did have more liberal attitudes to it, but I’ve reevaluated that and believe I should have more humility in my beliefs and approach. On stem cell research, there’s a lot of moral questions there. For one:

In January, 2008, Wood and Andrew French, Stemagen’s chief scientific officer in California, announced that they successfully created the first 5 mature human embryos using DNA from adult skin cells, aiming to provide a less-controversial source of viable embryonic stem cells. Dr. Samuel Wood and a colleague donated skin cells, and DNA from those cells was transferred to human eggs. It is not clear if the embryos produced would have been capable of further development, but Dr. Wood stated that if that were possible, using the technology for reproductive cloning would be both unethical and illegal. The 5 cloned embryos, created in Stemagen Corporation lab, in La Jolla, were later destroyed.

This was hailed by some as a solution to the ethical controversy but there seems to be a question of whether these 5 mature human embryos created from adult skin cells would be considered theologically speaking human life or human persons. IMO, they wouldn’t be in accordance with my previous response to you. But I don’t see how you could say they wouldn’t be.

I would not support at this time stem cell research that uses embryos that have already implanted – if that were some technique some wanted to use. But since that kind of technique is not at issue, for the techniques in use that I am aware of, I am of the opinion that it is OK. There is a potential moral pitfall I see with it however so my opinion is not a firm one and requires more prayerful study and reflection, including on church teaching.

Jennifer I have already addressed this. Please read my other posts.

Aquinas is not a scientist. Life begins at conception. An unfertilized egg is “alive” but not a human being. Skin cells are not a complete, whole, human being. A human zygote, created at conception, is a wholly unique human individual. Am I missing something? :smiley:

The points of Aquinas I introduced where not on the controverted issue of ensoulment but the uncontroversial issue of the various kinds of souls (something that Karl Keating adheres to I believe) and the relatively uncontroversial issue of a single guardian angel for both mother and child until birth has taken place. Some theologians disagree with Aquinas on that say that a guardian angel is not given to someone until baptism. So this is not an issue related to ensoulment obviously. Arguably Aquinas’ views on ensoulment can be said to have been contigent on mistaken scientific data but these views that I just cited are not. They are theological views and no scientific data contradicts them.

Aquinas also viewed science in a different way than we do today. He actually was not far from the President of Iran’s view of science (the one part of his speech at the American university which I did like, the only one I remember anyway). Science in Latin just means knowledge. Aquinas saw the scientific enterprise as a cohesive whole which included philosophy and theology both as branches of science (though in the case of theology proper it is a special case I won’t go into). The chair that Isaac Newton once occupied is still described as one of “natural philosophy”; at the time what we today call science was considered a branch of philosophy.

Anyway, I staunchly oppose the contemporary attitude of viewing natural science by today’s materialist scientific community as an authoritative peg by which other fields of human inquiry such as philosophy or theology should follow the lead on. Rather I think in many cases people overinterpret science, including the scientists themselves. For example, some say quantum mechanics proves there exists many parallel worlds. But that is a philosophical interpretation of a theory. Likewise given embryological data, one can give one or another philosophical interpretation of it. Natural science cannot produce philosophical results anymore than it can produce mathematical results (natural science properly speaking, not the mathematical work of physicists or economists) nor anymore than it can produce music. There are some with training and degrees in multiple fields who are in a unique position to give more IMO intelligent opinions than your ordinary scientist, philosopher, or theologian. (ex. John Polkinghorne)

Since there is no definitive or certainty of knowing isn’t it logical to assume then that life and soul begin at conception? As you point out it happens at some point why not at the very beginning - at conception?

From the article:

"It is important to appreciate that the scientific facts are themselves entirely neutral; they are simply a reflection of the way the world is, as opposed to how we may wish or imagine it to be.

That is not to say that the scientific facts lend equal support to any and all views of when human life begins. While people are free to formulate their opinion on when human life begins in any manner they choose (including belief and politics), not all opinions are equally consistent with factual reality. Those who choose to ignore the facts cannot expect their opinions to garner as much respect or to be given as much credibility as those who base their opinions in sound scientific observation and analysis."

Everyone has a right to theorize about when human life begins, and people of good will can disagree. However, it is all still theoretical at the philosophical sense. It can not be proven factually. The more scientific knowledge we have aquired on the subject, the more we can see that biological human life begins at conception.

This is an important distinction. The idea that life begins at implementation is inherently political and has consequences. This theory violates all known science and coincidentally enough, gained ground around the same time as the use of the birth control pill became normalized.

At least you seem to be consistent. I’d agree that your referenced scientists haven’t solved a thing. They’ve merely artificially conceived several clones of themselves and killed them off to farm them for body parts. Downright ghoulish. But from YOUR moral reasoning perspective, I’d not think you’d see a problem with what they’ve done.

I haven’t looked at your profile, but if you are catholic, how do you reconcile the Church ruling that IVF is inherently immoral as well as the similar ruling on embryonic stem cells. By your reasoning, there shouldn’t be too much difference between mesing with embryonic stem cells compared to experimenting on adult stem cells.

Things can be proven in philosophy.
Just as an aside and food for thought, seminarians are normally required to have the equivalent of an undergraduate degree in philosophy before studying theology.

No there may still be problems with it morally. Sorry if I misstated that. There may be moral problems apart from the question of whether it is murder etc. I just don’t think there’s any intrinsic moral problem to it that would make it wrong in any and all circumstances nomologically possible in this world.

I haven’t looked at your profile, but if you are catholic, how do you reconcile the Church ruling that IVF is inherently immoral as well as the similar ruling on embryonic stem cells. By your reasoning, there shouldn’t be too much difference between mesing with embryonic stem cells compared to experimenting on adult stem cells.

On IVF, see this post

I haven’t acquainted myself with all the material on stem cell issues so I can’t engage your question on that fully.

On my Catholicity see:

Hopefully the links will automatically work for your browser and browser settings.


The frontiers have been pushed back on science’s knowledge of early child development, and forward on our knowledge of late development. In the mid-20th Century, we thought people began forming hearts, nerves and skeletons at three weeks after conception and that these and the brain were fully formed by age 21. We now place the start of such structures at a mere six days (at implantation, which is a week earlier than we’d thought it was as well), and their completion at 26 years after birth. Perhaps in forty years we’ll find evidence of formation of nerves, spines and hearts at three days, and discover that the dish isn’t the perfect environment for growth and was atypical, and also learn that we never finish developing (already a valid and popular theory). Maybe forty years after that we’ll find out there is evidence of some kind of consciousness at conception, and a trace memory of it that lasts a lifetime, as some philosophies hold to already.
If not, we must consider the zygote a person asleep without dreaming, as most adults do several hours a night. If it isn’t OK to destroy and discard an adult who is sleeping non-REM, it isn’t OK to do the same to a zygote or embryo.

Yes, philospohy has its place, but as for the biological facts about when human life begins, it is clear it begins at conception. No amount of philosophy can dispute that.

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