• Life starts at conception but what about personhood?

    Growing up in heathen headquarters (aka central Europe), I never met anyone in meatspace who thinks that a fertilized human egg is a “fully human person”. I’ve met many Catholics in my life so far, but none of them would agree with the notion of a zygote having full personhood (disagreeing with the majority of official Church doctrines is quite common for Catholics in first world countries). Since this view is virtually non-existent where I live, I never had to debate it with anyone and, to be honest, I never really thought about this issue until recently. The first time I participated in a discussion on this issue was on JW Wartick´s blog (Jonathan already mentioned the discussion that ensued on his blog in this post). While Jonathan was mostly raising philosophical issues in this discussion, I was focused on whether the personhood-starts-at-conception position is defensible based on a 21st century understanding of Biology, especially Embryology. I think that this position is necessarily incoherent, and I want to summarize my argument for that here.

    A fertilized human egg is indeed “human life” – but so is an unfertilized egg, or a liver cell, or any other human cell (except for dead ones like hair cells, for example). Something being “alive” does not automatically imply that it deserves protection under the law. Bugs are alive, but laws against animal cruelty do not protect them – these laws usually apply to vertebrates only. If a fertilized human egg would be considered to have full personhood on the other hand, they obviously would deserve the same protection under the law that an adult human being enjoys. However, a big and unsolved problem with assigning personhood status is the fact that “personhood” has no universally, or even widely, accepted definition.

    To me, it seems obvious that “personhood” / “non-personhood” is not a binary state. Personhood develops on a continuum. Perception, feelings and emotions, consciousness, desires and fears, memories etc., are attributes that are commonly associated with “personhood” – and there is no discrete moment in time where a developing human gains all of these attributes at once. They gradually develop, with the ability to feel pain, for example, developing rather early in development while consciousness develops rather late. A fertilized human egg lacks all of these attributes, so why does it deserve any more rights than an unfertilized egg? Both are single cells lacking all attributes that are commonly associated with personhood, the only difference is a change in developmental potential. JW argued that this change in developmental potential is an objective demarcation criterion:

    Here’s where I see a difference: Unless one actively interferes with the fertilized egg, or some natural process terminates the pregnancy, it will develop into a human being. An unfertilized egg has none of these properties. Your argument tries to ignore the extreme disanalogies between the two states (fertilized and non).
    Let me put it to you in a question: are you suggesting there is no rational discontinuity between the fertilized egg and the unfertilized egg?

    A fertilized human egg indeed does have the potential to develop into an adult human being, but only under some conditions:

    1. The fertilized egg manages to correctly move to the uterus and correctly attach to the uterine wall (which fails in >50% of all cases where the embryo will be aborted naturally, without any human intervention).

    2. The embryo develops into a fetus without abnormalities (fails in ~15% of all cases, again leading to the embryo (or fetus, depending on stage of development) being aborted naturally without any human intervention).

    3. The mother stays alive and healthy until the fetus reaches a stage of development where it is viable outside the womb of the mother.

    For the unfertilized egg, you just have to add another condition:

    4. The egg has to be fertilized.

    So yes, there is a “rational discontinuity” between a fertilized egg and an unfertilized one – the unfertilized one needs one extra condition being fulfilled to develop into a human being. But why should this extra condition lead to a different legal and / or moral status for fertilized eggs compared to unfertilized ones ?

    However one chooses to define “personhood”, if one argues that it starts at conception, one reduces it to a biochemical triviality.

    The main differences between a fertilized and an unfertilized egg is, that the fertilized egg possesses now 46 chromosomes instead of 23 and is “totipotent”. Having a full human complement of 46 chromosomes cannot possibly be a criterion for distinguishing personhood from non-personhood because this attribute is shared by virtually all human cells (all except for red blood cells and gametes).

    So, if “personhood” indeed starts at conception, it must be a consequence of totipotency, since this is the only attribute that distinguishes a fertilized human egg from most other human cells. The “potency” of a cell specifies the different cell types a particular cell can differentiate into and “totipotency” means that the cell can divide and produce all differentiated cell types of an organism and thus ultimately develop into an adult form of the organism. Changes in potency are based on epigenetic “reprogramming”, which could also be induced in the lab. It has already been demonstrated that pluripotency (similar to totipotency, pluripotent cells can differentiate into all cell types except for extraembryonic tissues like the placenta) can be reactivated in specialized cells – the 2012 Nobel prize for physiology or medicine has been awarded for this discovery. Recent research indicates that reactivating totipotency is also possible.

    If “personhood” starts at conception – it is a consequence of triggering the right genetic switches, which is a process that is reversible in principle. Assigning “personhood” to a fertilized egg detaches “personhood” from everything that we commonly associate with it – perception, feelings and emotions, consciousness, desires and fears, memories – all attributes that the egg doesn’t have, never had, and is not going to have unless it survives a long and failure-prone developmental process. Personhood is reduced to a biochemical triviality.

    A religious person would probably disagree with my assessment of personhood being trivialized by assigning it to a fertilized human egg – (s)he might argue that “personhood” is a cosequence of possessing a human “soul” and (s)he might further argue that conception is the precise moment where a developing human is granted a “soul” by his / her favored deity. Since the existence of a “soul” cannot be demonstrated (and is incredibly implausible based on a modern understanding of physics as brilliantly argued by Sean Carroll here), it cannot possibly be a foundation for secular law. However, even if one would grant a believer the existence of “souls” and the notion that “personhood” is a consequence of possessing a “soul”, the idea that ensoulment happens at the precise moment of conception is still absurd.

    All cells in the developing embryo are identical copies of the zygote until the 16-cell stage. Each of those cells is totipotent. Each of those cells has the potential to develop into an adult human being! In fact, it is quite common that more than one adult human beings can trace their origin back to the same zygote – monozygotic twins (aka identical twins) are not uncommon and even monozygotic triplets exist.

    Does this mean that whatever deity grants “souls” at the moment of conception is giving the zygote two souls at conception if it knows that it will develop into monozygotic twins (and three “souls” for monozygotic triplets)?

    And if “personhood” is based on having a “soul”, does that mean that such zygotes are actually two / three persons all condensed into a single(!) cell ? This view is obviously incoherent.

    But it gets worse. The development of monozygotic twins can be induced by embryo splitting, a technique that is actually used in reproductive medicine (see http://www.sciencedirect.com/science/article/pii/S001502820804795X ). What does God do when we apply this technique? Does he create a second soul for the splitt embryo that we created (note that we are already at the embryo stage, several days after conception)? Could we really force almighty God to create souls that he didn’t plan in advance? Or does one of the identical twins grow up without a soul?

    Personhood starting at conception is a hopelessly incoherent position – even if one would grant believers the existence of “souls” and would further grant them that ensoulment happens at the precise moment of conception.

    Category: HealthPhilosophyScience

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    Article by: Andreas Schueler

    • An excellent and concise post, Andreas. Great stuff. I have often argued this but without the backing of good embryological knowledge.

      • Andy_Schueler

        Thanks! The links seem to be broken, I think there´s an extra quote sign at the end of the URL – could you check that ?

    • Outstanding post!

      I very much enjoy arguments laid out in a concise, scientific manner as opposed to the apologist’s appeal to unverifiable supernaturalism. It’s just a breath of fresh air! 
      Well done, sir.

    • Copyleft

      Which is why my own standard (admittedly subjective) is tied to neurological activity. Without a brain, there is no person–as the Terri Schiavo case amply illustrated on the other end of life.

    • I’m not the best person to defend the Catholic position (assuming I am getting it entirely right in the first place) but I do find Thomist thought intriguing (and convincing in many areas). Here’s how I think they might respond.

      However, a big and unsolved problem with assigning personhood status is the fact that “personhood” has no universally, or even widely, accepted definition.

      From the Thomist perspective a person is a rational animal. Note that this definition is known only to cover homo sapiens but could, in theory, cover other species. Under this definition a fertilized egg is a person because it is an entity whose essence is that of a rational animal (even if it is not rational at the moment of conception). Unfertilized eggs, liver cells, and hair cells do not have the essence of a rational animal.

      A fertilized human egg lacks all of these attributes, so why does it deserve any more rights than an unfertilized egg? Both are single cells lacking all attributes that are commonly associated with personhood, the only difference is a change in developmental potential.

      An unfertilized egg does not contain the potential to have the attributes listed and remain an unfertilized egg. On the other hand, a fertilized egg does have the potential to have the attributes listed and remain a person.

      So yes, there is a “rational discontinuity” between a fertilized egg and an unfertilized one – the unfertilized one needs one extra condition being fulfilled to develop into a human being. But why should this extra condition lead to a different legal and / or moral status for fertilized eggs compared to unfertilized ones?

      It is not the lack of the extra condition that confers moral status on the embryo. It is simply the difference in the essence between the two entities.

      Assigning “personhood” to a fertilized egg detaches “personhood” from everything that we commonly associate with it – perception, feelings and emotions, consciousness, desires and fears, memories – all attributes that the egg doesn’t have, never had, and is not going to have unless it survives a long and failure-prone developmental process.

      But the Thomist definition of personhood is attached to rationality. It’s just that you don’t have to be rational at this very moment to have a right to life. As long as you have the essence of a rational animal you are covered.

      What does God do when we apply this technique? Does he create a second soul for the splitt embryo that we created (note that we are already at the embryo stage, several days after conception)? Could we really force almighty God to create souls that he didn’t plan in advance? Or does one of the identical twins grow up without a soul?

      The soul is the form of the person. If an embryo is split then there are two persons and therefore two souls. This does not surprise God or force him to act (at least no more than he is forced to act if I were to split a starfish in two).

      • Andy_Schueler

        Hi Jayman,

        From the Thomist perspective a person is a rational animal. Note that this definition is known only to cover homo sapiens but could, in theory, cover other species. Under this definition a fertilized egg is a person because it is an entity whose essence is that of a rational animal (even if it is not rational at the moment of conception). Unfertilized eggs, liver cells, and hair cells do not have the essence of a rational animal.

        What exactly is an “essence” and how do you know that it exists? 

        An unfertilized egg does not contain the potential to have the attributes listed and remain an unfertilized egg. On the other hand, a fertilized egg does have the potential to have the attributes listed and remain a person.

        An unfertilized egg does have the potential to develop into a human being and develop all those attributes – it just needs one extra condition to be fulfilled compared to a fertilized one. 
        Why do choose exactly this point in development (conception) instead of a later point (e.g. implantation) or an earlier point (e.g, ovulation) ? Isn´t this arbitrary ?

        It is not the lack of the extra condition that confers moral status on the embryo. It is simply the difference in the essence between the two entities.

        I already asked you to define “essence” – here I´d like to add: how do you know that the “essence”, however it is defined, is attached to the egg at the moment of conception instead of an earlier or later point in development ? 
        Also, since the difference between a fertilized and an unfertilized human egg is nothing but some added genetic material + some epigenetic reprogramming, don´t you think it reduces the “essence”, whatever it is, to nothing but some biochemistry (biochemical processes that are fully reversible  to boot) ?

        But the Thomist definition of personhood is attached to rationality. It’s just that you don’t have to be rational at this very moment to have a right to life. 

        Assuming that conception is the precise moment where an egg starts to have a “right to life” – this would have very interesting legal implications. The process of implantation (the fertilized egg moving to the uterus (and dividing a few times) and attaching to the uterine wall) fails more often than not (between 50 and 60% of the time), leading to the embryo being aborted without any human intervention (and the woman usually has no way to notice that she carried an embryo for a few days in these cases). 
        So, if a fertilized egg has a “right to life” – wouldn´t the only logical approach be to place all sexually mature women under constant medical supervision to “rescue” embryos that failed to undergo proper implantation, and to try to assist with embryo implantation with the toolkit of reproductive medicine ? (without the woman having a choice to refuse to participate in this procedure of course) 
        Would you agree with this approach ? If not, why ? 

        The soul is the form of the person. If an embryo is split then there are two persons and therefore two souls.

        So, the Zygote at first had one “soul” and one “essence”, and as soon as the embryo is split – one of the two embryos gets a second “soul” + “essence” ? (note that embry splitting happens several days after conception) Or did the Zygote had several “souls” + “essences” all condensed into a single cell ? 

        •  

          What exactly is an “essence” and how do you know that it exists?

          An essence is the nature of an entity that makes it the kind of thing that it is. For example, having three sides is part of the essence of a triangle. Something like an essence seems presupposed any time we note similarities and differences between items. Merely asking whether an embryo is a person presupposes that both embryos and persons have some common nature that identifies them as a class of entities.

          An unfertilized egg does have the potential to develop into a human being and develop all those attributes – it just needs one extra condition to be fulfilled compared to a fertilized one.

          I’m not denying that. I’m saying that once an unfertilized egg is fertilized it is no longer an unfertilized egg.

          Why do choose exactly this point in development (conception) instead of a later point (e.g. implantation) or an earlier point (e.g, ovulation)? Isn´t this arbitrary?

          Because the moment of conception is the moment when a person’s essence comes into being. At implantation the person’s essence already exists. At ovulation the person’s essence does not exist.

          how do you know that the “essence”, however it is defined, is attached to the egg at the moment of conception instead of an earlier or later point in development?

          It is not in the nature of an unfertilized egg to turn into a rational animal (without changing its nature). But it is in the nature of a zygote to turn into a rational animal (without changing its nature).

          Also, since the difference between a fertilized and an unfertilized human egg is nothing but some added genetic material + some epigenetic reprogramming, don´t you think it reduces the “essence”, whatever it is, to nothing but some biochemistry (biochemical processes that are fully reversible  to boot)?

          The rational part of “rational animal” is immaterial so it can’t be reduced to biochemistry. And even if humans were entirely material Thomists are not reductionists. Also, isn’t this reductionism what most atheists do anyway?

          So, if a fertilized egg has a “right to life” – wouldn´t the only logical approach be to place all sexually mature women under constant medical supervision to “rescue” embryos that failed to undergo proper implantation, and to try to assist with embryo implantation with the toolkit of reproductive medicine?

          It depends on how you view the right to life. If it merely means that you can’t kill other persons then letting embryos die through this natural process does not need to be actively prevented. (I realize there could be many other angles to question your scenario’s morality but I’m trying to focus on the main issue.) I believe this is why the Catholic Church opposes euthanasia but is okay with withholding care at the end of life.

          So, the Zygote at first had one “soul” and one “essence”, and as soon as the embryo is split – one of the two embryos gets a second “soul” + “essence” ?

          That is what my understanding of Thomism implies. Although I would be interested in more expert opinion on the matter.

          • Andy_Schueler

            An essence is the nature of an entity that makes it the kind of thing that it is. For example, having three sides is part of the essence of a triangle. Something like an essence seems presupposed any time we note similarities and differences between items. Merely asking whether an embryo is a person presupposes that both embryos and persons have some common nature that identifies them as a class of entities.

            But what would be the “common nature” between a zygote and a human person ? As I noted, a Zygote has none of the attributes that are commonly associated with “personhood” – not a single one. On what grounds would you classify a fertilized egg as a human person but not an unfertilized one ?

            I’m not denying that. I’m saying that once an unfertilized egg is fertilized it is no longer an unfertilized egg.

             Obviously. But no two stages of human development are identical to each other (it´s called “development” for a reason) – my question is: what makes this particular step in development so important ? 

            Because the moment of conception is the moment when a person’s essence comes into being. At implantation the person’s essence already exists. At ovulation the person’s essence does not exist.

            But why ? You said that an “essence” is the “nature of an entity that makes it the kind of thing that it is” – what exactly do you mean by “nature of the entity” in this case ? Which attribute distinguishes the Zygote from an unfertilized egg and is sufficient to classify it as a human person ? (again, they are both single cells, lacking ALL attributed commonly associated with personhood and the only difference is some added genetic material and some epigenetic reprogramming (i.e. nothing but simple biochemistry))

            It is not in the nature of an unfertilized egg to turn into a rational animal (without changing its nature). But it is in the nature of a zygote to turn into a rational animal (without changing its nature).

            Without changing it´s nature ?? You´ve got to be kidding. If many million cell divisions, involving differentiation into more than a hundred specialized cell types and dozens of different tissues + the formation of many billion neurons with ~100 trillion (yes, trillion) synaptical connections between them, all developing from a single(!!) cellis not “changing it´s nature” then nothing is. The differences between a Zygote and a newborn are extensive enough to fill many books, the difference between a Zygote and an unfertilized egg can be summarized in a sentence: the egg gets 23 additional chromosomes and is epigenetically reprogrammed for totipotency. 
            Sorry, but this is just beyond ridiculous. 

            The rational part of “rational animal” is immaterial so it can’t be reduced to biochemistry.

            Then you have to argue that something “immaterial” (see also here: http://blogs.scientificamerican.com/guest-blog/2011/05/23/physics-and-the-immortality-of-the-soul/ ) is attached to the egg at the moment of conception – how could you possibly know that this is true ?

            And even if humans were entirely material Thomists are not reductionists. Also, isn’t this reductionism what most atheists do anyway?

            Nope.

            It depends on how you view the right to life. If it merely means that you can’t kill other persons then letting embryos die through this natural process does not need to be actively prevented. (I realize there could be many other angles to question your scenario’s morality but I’m trying to focus on the main issue.) I believe this is why the Catholic Church opposes euthanasia but is okay with withholding care at the end of life.

            These are certainly very strange ethics – it is ok to extend human life for many decades by “unnatural” means, but ending it to prevent suffering is not acceptable, and it is also ok to let millions of embryos die without doing anything whatsoever about it, but aborting one actively, even if it could save a life or prevent immense suffering, is completely unacceptable. This just seems to be rather evil to me. 

            • Andy, I’ve answered many of your latest questions above in one form or another. I’ll reiterate my points but I don’t claim that I can make Thomist metaphysics, as a whole, click for you.

              But what would be the “common nature” between a zygote and a human person? … On what grounds would you classify a fertilized egg as a human person but not an unfertilized one?

              Being a rational animal is the essence of personhood. A zygote, by its nature, has this potential within it. An adult homo sapien often actually exhibits being a rational animal, but even an adult homo sapien may only have this potential within him (e.g., if he was unconscious). An unfertilized egg does not have this potential in its nature. It only achieves this potential by changing its nature when it’s fertilized.

              But no two stages of human development are identical to each other (it´s called “development” for a reason) – my question is: what makes this particular step in development so important ?

              Conception is the start of a human’s existence. You can’t have human development without a human.

              Which attribute distinguishes the Zygote from an unfertilized egg and is sufficient to classify it as a human person ?

              The zygote’s inherent potential to become a rational animal.

              Many million cell divisions, involving differentiation into more than a hundred specialized cell types and dozens of different tissues + the formation of many billion neurons with ~100 trillion (yes, trillion) synaptical connections between them, allowing for perception, feelings and emotions, consciousness, desires and fears, memories etc. is not “changing it´s nature” then nothing is.

              Those are examples of a person actualizing his potential(s). None of those changes involve the person losing his potential to be rational or to be an animal.

              Sorry, but this is just beyond ridiculous.

              It might seem that way but I encourage you to seriously consider what it means to be a person. You’ve hinted at answers but have not given a clear definition.

              Then you have to argue that something “immaterial” (see also here: http://blogs.scientificamerica… ) is attached to the egg at the moment of conception – how could you possibly know that this is true ?

              This touches on the philosophy of mind. I’m convinced that something like intentionality cannot, in principle, exist in matter. From direct introspection I know that the mind exhibits intentionality and therefore cannot be solely material. So at some point an immaterial part of the mind is “attached” to a person.

              The real question, for me, is whether a zygote who does not yet exhibit rationality has an immaterial mind or not. That’s a fair question that I don’t have a convincing answer for either way.

              These are certainly very strange ethics – it is ok to extend human life for many decades by “unnatural” means, but ending it to prevent suffering is not acceptable,

              Extending life through medicine allows a person to flourish by fulfilling his natural ends. And I was describing the Catholic Church’s stance (as I understand it) not defending it in each and every way. I’m not a Catholic. Like your hypothetical scenario with embryo-saving, euthanasia touches on many other areas than just the nature of personhood.

              and it is also ok to let millions of embryos die without doing anything whatsoever about it, but aborting one actively, even if it could save a life or prevent immense suffering, is completely unacceptable.

              I did not say I oppose abortion in all cases (e.g., saving the life of the mother). For more thoughts about natural embryo destruction see http://www.thepublicdiscourse.com/2008/12/103/

            • Being
              a rational animal is the essence of personhood. A zygote, by its nature, has
              this potential within it. An adult homo sapien often actually exhibits being a
              rational animal, but even an adult homo sapien may only have this potential
              within him (e.g., if he was unconscious). An unfertilized egg does not have
              this potential in its nature. It only achieves this potential by changing its
              nature when it’s fertilized.

               

              You
              are speaking of potential as if it has some existence properties, which is
              problematic. What is the ontology of potential? It is nothing more than a
              concept. A rock has the potential of being a sculpture – a work of art. But by
              destroying the rock, I am in no way evoling the destruction of the work or art
              (which does not exist).

               

              Conception is the start of a human’s existence.
              You can’t have human development without a human.

               

              You
              cannot have a developed human without an egg or sperm, either.

               

              The
              zygote’s inherent potential to become a rational animal.

               

              I
              think you are not addressing Andy’s point well enough here. ‘inherent’ is
              problematic. The potential is identical but requires one more process.  A fertilized egg cannto become a human being without
              the successful implantation to the uterine wall. The potential can only be
              realised with this event being realised.

               

              Just
              like the unfertilised egg can only reach its potential with the event of
              fertilisation being realised.

               

              Those are examples of a person actualizing his
              potential(s). None of those changes involve the person losing his potential to
              be rational or to be an animal.

               

              Of
              course, this raises the point that many humans in vegetative states, or having
              lost their rationality are no longer humans.

               

              It might seem that way but I encourage you to
              seriously consider what it means to be a person. You’ve hinted at answers but
              have not given a clear definition.

               

              I
              would argue there isn’t a clear definition because the form does not exist objectively,
              in some kind of Platonic realm, but inside the conceptual minds of humans – ie some
              kind of conceptual nominalism.

               

              This touches on the philosophy of mind. I’m
              convinced that something like intentionality cannot, in principle, exist in
              matter. From direct introspection I know that the mind exhibits intentionality
              and therefore cannot be solely material. So at some point an immaterial part of
              the mind is “attached” to a person.

              The
              real question, for me, is whether a zygote who does not yet exhibit rationality
              has an immaterial mind or not. That’s a fair question that I don’t have a
              convincing answer for either way.

               

              This
              is a much bigger discussion than the scope for this post allows, as well as the
              fact that the philosophy of mind is the most contested area of philosophy and
              science.

               

              Extending life through medicine allows a person
              to flourish by fulfilling his natural ends.

               

              That
              ‘begs the question’ in the sense that it assumes we have ‘ends’ which assumes a
              designer which has created ‘ends’ for lifeforms to realise.

               

            •  

              You are speaking of potential as if it has some existence properties, which is problematic. What is the ontology of potential? It is nothing more than a concept. A rock has the potential of being a sculpture – a work of art. But by destroying the rock, I am in no way evoling the destruction of the work or art (which does not exist).

              It is far more problematic to think of potential as merely a concept than to think of it as having “existence properties”. If it is merely a concept then it is difficult to explain how a potential is ever actualized at all. Certainly the potential for a zygote to become a newborn is not merely a concept in someone’s mind but an actual property of the zygote. Andreas grants as much when he writes: “The ‘potency’ of a cell specifies the different cell types a particular cell can differentiate into and ‘totipotency’ means that the cell can divide and produce all differentiated cell types of an organism and thus ultimately develop into an adult form of the organism. Changes in potency are based on epigenetic ‘reprogramming’, which could also be induced in the lab.” There is your potential.

              Your rock/sculpture example is dis-analogous for a couple reasons. First, a rock does not have the inherent potential to be a sculpture. This potential is imposed on it from the outside, from the sculptor. Second, sculpting a rock does not result in the destruction of the rock’s essence. It is still a rock, it just now has a different shape.

              I think you are not addressing Andy’s point well enough here. ‘inherent’ is problematic. The potential is identical but requires one more process.

              The key point is that a zygote has a different essence than an unfertilized egg or a sperm cell. Attaching to the uterine wall does not change its essence.

              Of course, this raises the point that many humans in vegetative states, or having lost their rationality are no longer humans.

              Since some people in vegetative states have communicated with outsiders I don’t think we can say they have lost their rationality. But supposing some people do lose their rationality they still have the human essence until their death. And if someone is going to define person-hood based on, say, consciousness then we gain and lose our person-hood quite often.

              I would argue there isn’t a clear definition because the form does not exist objectively, in some kind of Platonic realm, but inside the conceptual minds of humans – ie some kind of conceptual nominalism.

              If that’s the case then what is wrong with murdering an adult human being? He is no more objectively a person than a zygote, right?

              That ‘begs the question’ in the sense that it assumes we have ‘ends’ which assumes a designer which has created ‘ends’ for lifeforms to realise.

              That we (everything, not just lifeforms) have “ends” in the sense of “final causes” is obvious. When Andreas is speaking of a cell that can turn into a different kind of cell he is speaking of final causes (yes, final causes and potency/potential are intricately linked). In his Fifth Way Aquinas argues from the existence of final causes to the existence of God. If you accept this argument it is not that we assume a “designer”, rather we deduce the existence of a designer (but this should not be confused with the intelligent design movement).

            • It is far more problematic to think of potential as merely a concept than to think of it as having “existence properties”. If it is merely a concept then it is difficult to explain how a potential is ever actualized at all. Certainly the potential for a zygote to become a newborn is not merely a concept in someone’s mind but an actual property of the zygote.

              Jayman, you are way off here, I think. You are claiming, explicitly, that a potential of a zygote is an actual property. So a future event is a present fact? OK, so on B Theory of time, this may be (but you can also jettison free will etc), but on normal understanding of terminology, this is hugely incoherent. Not least because of this:

              i have the potential to be gay, straight and bisexual. i have the potential to be dead in 5 minutes or alive. I have the potential for an almost infinite amount of things. Well, actually, if you can infinitely divide things up, then I have an infinite potentials. And for these to actually exist, first of all it breaks the ‘rule’ that there are no actual infinites. Second of all, you have an organism with infinite properties.

              No, potentials are conceptual.

              Changes in potency are based on epigenetic ‘reprogramming’, which could also be induced in the lab.” There is your potential.

              Er, there is a genetic and epigenetic programme. I think you really need to define potential here.

              Your rock/sculpture example is dis-analogous for a couple reasons. First, a rock does not have the inherent potential to be a sculpture.

              So here you illustrate your incoherence. You define a potential in a form of special pleading. Who are you to define what is an ‘inherent’ potential? It seems that potential is synonymous with programmed. The thing that exists is the programme, not some nebulous idea as ‘potential’ (unless you define potential as programme). 

               But supposing some people do lose their rationality they still have the human essence until their death.

              You have now contradicted your definition of essence.

              If that’s the case then what is wrong with murdering an adult human being? He is no more objectively a person than a zygote, right?

              This is what we have morality for. This is a whole other massive conversation.

              The rest of your post assumes the consequent. I don’t think anything has objective ends. We create ends and the means towards the end. This is the meaning of life. See my essay on the meaning of life in the essays tab above.

            • You are claiming, explicitly, that a potential of a zygote is an actual property. So a future event is a present fact?

              No. The potential to be an adult human inheres in the zygote but that does not mean the zygote is an adult human.

              I have the potential for an almost infinite amount of things.

              Your potential is limited by your human nature. It is certainly not infinite. For example, you have the potential to convert certain kinds of foods into energy but not others.

              Er, there is a genetic and epigenetic programme. I think you really need to define potential here.

              Perhaps think of it as a power, ability, or capability. Different things have different potentials based on the kind of thing they are.

              You have now contradicted your definition of essence.

              I said at the outset that a person may not always exhibit every aspect of his nature.

              This is what we have morality for.

              I thought we have morality for discerning how persons should treat each other. If persons don’t truly exist then morality for persons seems pointless.

            • Andy_Schueler

              Jayman,

              Being a rational animal is the essence of personhood. A zygote, by its
              nature, has this potential within it. An adult homo sapien often
              actually exhibits being a rational animal, but even an adult homo sapien
              may only have this potential within him (e.g., if he was unconscious).
              An unfertilized egg does not have this potential in its nature. It only
              achieves this potential by changing its nature when it’s fertilized.

              You are selecting an arbitrary point in a continuum. You say that the unfertilized egg does not have the potential to be a rational animal without changing it´s nature, but the exact same is true for the fertilized one. There are billions of developmental steps that change the nature of the developing human before it can become a conscious being. You select one developmental step (conception) and simply ignore all others.
              The comparison to an unconscious human being is inappropriate, it´s like saying that Da Vinci´s Mona Lisa and a bucket full of paint have the same potential within them because you could hide the beauty of the Mona Lisa behind a curtain (just like an adult human could loose consciousness temporarily).

              Conception is the start of a human’s existence. You can’t have human development without a human.

              Human development is a cycle, the zygote grows to become an adult male or female, which produce sperm and egg cells, which fuse to form new zygotes, and the cycle continues. The actors at every step of this cycle are “human life”, and we ask why the fertilized egg deserves any more rights than an unfertilized egg or a sperm cell.

              Andy: Which attribute distinguishes the Zygote from an unfertilized egg and is sufficient to classify it as a human person ?

              Jayman: The zygote’s inherent potential to become a rational animal.

              Again, you are focussing on one developmental step, and ignore billions of others. If the Zygote is 1000000 developmental steps aways from being a human person, then an unfertilized egg is 1000001 steps away.

              Those are examples of a person actualizing his potential(s). None of
              those changes involve the person losing his potential to be rational or
              to be an animal.

              Why are those examples of the Zygote “actualizing it´s potential” while conception is not an example of the unfertilized egg “actualizing it´s potential” ?

              It might seem that way but I encourage you to seriously consider what it
              means to be a person. You’ve hinted at answers but have not given a
              clear definition.

              See Jonathan´s answer to that.

              This touches on the philosophy of mind. I’m convinced that something
              like intentionality cannot, in principle, exist in matter. From direct
              introspection I know that the mind exhibits intentionality and therefore
              cannot be solely material. So at some point an immaterial part of the
              mind is “attached” to a person.

              You don´t know how your brain could mediate intentionality if materialism is true, so you conclude that your mind has immaterial components – but you still don´t know how your mind generates intentionality, you have just replaced a materialistic unknown with an immaterial unknown. How our mind works is not well understood, but what is very well understood is what stuff our brain is made of and how this stuff interacts with each other – if there is anything but the known fundamental particles interacting with the stuff that our brain is made of, we would have found it (we found the Higgs-Boson after all, finding particles or forces that are detectable at everyday energies and distances is trivial compared to that).

              The real question, for me, is whether a zygote who does not yet exhibit rationality has an immaterial mind or not.

              If they do, and we could create new “immaterial minds” by simply splitting embryos, doesn´t this “immaterial mind” seem to be a pretty trivial thing ?

            •  

              You are selecting an arbitrary point in a continuum. You say that the unfertilized egg does not have the potential to be a rational animal without changing it´s nature, but the exact same is true for the fertilized one.

              It’s not arbitrary because the essence of a fertilized egg is a rational animal while this is not the case for an unfertilized egg. And no, the essence of a zygote does not change as it develops (unless it dies).

              The actors at every step of this cycle are “human life”, and we ask why the fertilized egg deserves any more rights than an unfertilized egg or a sperm cell.

              Because a sperm cell is not human in the same sense that a zygote is. On your view, why does a grown adult human deserve any more rights than a sperm cell?

              Again, you are focussing on one developmental step, and ignore billions of others. If the Zygote is 1000000 developmental steps aways from being a human person, then an unfertilized egg is 1000001 steps away.

              I’m not focusing on developmental steps. I’m focusing on the essence of the item in question.

              Why are those examples of the Zygote “actualizing it´s potential” while conception is not an example of the unfertilized egg “actualizing it´s potential” ?

              Conception is the actualizing of a potential but it, unlike the growth of a zygote, is also the coming into existence of a new essence.

              You don´t know how your brain could mediate intentionality if materialism is true, so you conclude that your mind has immaterial components – but you still don´t know how your mind generates intentionality, you have just replaced a materialistic unknown with an immaterial unknown.

              The basic argument would as follows: (1) the mind exhibits intentionality; (2) matter does not exhibit intentionality; (3) therefore the mind is not (entirely) material. It is not an argument from ignorance. That is not to say there are not unknowns.

              How our mind works is not well understood, but what is very well understood is what stuff our brain is made of and how this stuff interacts with each other – if there is anything but the known fundamental particles interacting with the stuff that our brain is made of, we would have found it (we found the Higgs-Boson after all, finding particles or forces that are detectable at everyday energies and distances is trivial compared to that).

              There’s tension in that statement. On the one hand, you believe matter is very well understood. On the other hand, you believe the mind (which is just matter on your view, right?) is not well understood. A dualist account (in one form or another) of the mind lacks this tension.

              And I’m quite skeptical that science would have found the immaterial mind if it exists. You are already hedging your bets when you appear to assume the immaterial mind would be working at “everday energies and distances”. What if it doesn’t work at an everyday energy or distance? What if the universe is not causally closed?

              If they do, and we could create new “immaterial minds” by simply splitting embryos, doesn´t this “immaterial mind” seem to be a pretty trivial thing ?

              How is it any more trivial than human life in general?

            • Andy_Schueler

              It’s not arbitrary because the essence of a fertilized egg is a rational animal while this is not the case for an unfertilized egg. And no, the essence of a zygote does not change as it develops (unless it dies).

              So you claim that there is something like a “human essence” and that a fertilized egg has it (and the same “essence” as an adult human being to boot) while the unfertilized egg does not have this “essence”. This is first of all nothing but a mere assertion – how do you know that this is true ? – and second, the term “essence” does not seem to be a useful description of anything if two extremely similar objects (fertilized and unfertilized eggs ) have completely different “essences” while two very different objects (fertilized eggs and adult human beings) have the same “essence”, how does this make any sense ? 

              Because a sperm cell is not human in the same sense that a zygote is.

              Why ? 

              On your view, why does a grown adult human deserve any more rights than a sperm cell?

              A fruit fly has as much rights as a sperm cell (none). A cow has more rights than a sperm cell (protected by laws against animal cruelty in most developed countries). And a human has more rights than a cow. The ability to feel pain and pleasure is obviously important in determining the rights of an animal (it´s why a cow has rights while a fly has none) – for humans, you are dealing with an animal that has not only feelings and emotions, but also desires and fears, memories, relationships, and so on. 

              Conception is the actualizing of a potential but it, unlike the growth of a zygote, is also the coming into existence of a new essence.

              And why does the essence come into existence at this step ? Why didn´t the egg already have the essence before conception and has to actualize just one tiny developmental step more than the fertilized one ? Don´t you see that you are trying to impose a binary state on a continuum ? (and selecting a completely arbitrary point in time where this binary state changes to boot)

              The basic argument would as follows: (1) the mind exhibits intentionality; (2) matter does not exhibit intentionality; (3) therefore the mind is not (entirely) material. It is not an argument from ignorance. That is not to say there are not unknowns.

              But this is a circular argument. Premise 2 already contains the conclusion that materialism is false. 

              There’s tension in that statement. On the one hand, you believe matter is very well understood. On the other hand, you believe the mind (which is just matter on your view, right?) is not well understood.

              This is not a contradiction, the laws underlying the physics of everyday life are completely understood, but how these laws play out on macroscopic scales is not, see:
              http://blogs.discovermagazine.com/cosmicvariance/2010/09/23/the-laws-underlying-the-physics-of-everyday-life-are-completely-understood/
              and:
              http://blogs.discovermagazine.com/cosmicvariance/2010/09/29/seriously-the-laws-underlying-the-physics-of-everyday-life-really-are-completely-understood/
               

              A dualist account (in one form or another) of the mind lacks this tension.

              I don´t think so, a dualist account provides no additional explanatory power to explain the human mind compared to what we currently can explain within a materialistic framework (if you disagree, which phenomenon can be scientifically explained with a dualistic theory of mind but not with a materialistic one ?) – all the dualistic explanation does is adding new entities that provide no additional explanatory power and are completely unexplained themselves.

              And I’m quite skeptical that science would have found the immaterial mind if it exists. You are already hedging your bets when you appear to assume the immaterial mind would be working at “everday energies and distances”. What if it doesn’t work at an everyday energy or distance? What if the universe is not causally closed?

              It does work at everyday energies and distances (by that I mean the conditions under which your brain actually works – an example for non-everyday energies would be the inside of a particle accelerator, or the inside of a Supernova). And if the universe is not causally closed, you still have the problem that the laws of physics describe the behaviour of the particles that your brain is made of precisely, if an outside force would interact with your brain, how could that be possible ? 

              How is it any more trivial than human life in general?

              I don´t think that the human experience is trivial at all. But I do think that the epigenetic reprogramming during conception is absolutely trivial compared to the attributes that are commonly associated with personhood which I mentioned in the OP.

            •  

              how do you know that this is true ?

              Because conception is the point at which the entity, as a unity, begins to be directed towards rational animality. The 23 chromosomes of an oocyte/sperm are not enough.

              The ability to feel pain and pleasure is obviously important in determining the rights of an animal (it´s why a cow has rights while a fly has none) – for humans, you are dealing with an animal that has not only feelings and emotions, but also desires and fears, memories, relationships, and so on.

              I’m not sure a cow does not have feelings, emotions, desires, fears, memories, and relationships. And if these are the conditions that give a human moral worth then a number of moral issues arise. If an unconscious person does not have feelings, emotions, desires, or fears at the moment does he not have moral worth? Does someone with amnesia lack moral worth? Does a loner lack moral worth?

            • Andy_Schueler

              Because conception is the point at which the entity, as a unity, begins to be directed towards rational animality. The 23 chromosomes of an oocyte/sperm are not enough.

              With conception you have selected an arbitrary point in development. Your argument is, that the fertilized egg is “directed towards rational animality” and thus has the “essence” of a rational animal. But all steps in development are directed towards the development of an adult organism, so I could construct an identical argument for every conseivable developmental step. I could choose meiosis and argue that the precursor egg lacks the “essence” of a rational animal while the resulting haploid egg has this essence. I could do the same for implantation and argue that the implanted embryo has the “essence” of a rational animal while the Zygote or the embryo before implantation didn´t have it. In general, the argument would be:
              [Step in development x] does not have the essence of a rational animal, but [step in development y] does – and I could construct this argument for all combinations of developmental steps as long as y comes after x. Each of those arguments is just as arbitrary as your one (where x is gametogenesis and y is conception). 
              They are all equally arbitrary because the entire process is a cycle – gametes are produced, fertilized, divide and differentiate to form an adult human being, and the whole cycle starts over – the entire process is “directed towards the development of a rational animal”. 
              You are imposing a binary state on a continuum, and you have choosen a completely arbitrary point in the continuum where the binary state changes.

              I’m not sure a cow does not have feelings, emotions, desires, fears, memories, and relationships. And if these are the conditions that give a human moral worth then a number of moral issues arise. If an unconscious person does not have feelings, emotions, desires, or fears at the moment does he not have moral worth? Does someone with amnesia lack moral worth? Does a loner lack moral worth?

              These clearly are the issues that give an animal moral worth – just ask yourself if you´d rather save an unconscious nurse or a patient in a permanent vegetative state if you are in a burning hospital and you can only save one of them. Would you rather save a box full of frozen embryos than one newborn baby if you could only save one of them ? Would you rather save a dog than a hermit crab ? Virtually all humans give the same answers to these questions.
              When it comes to humans that are unconscious, or in a coma, or in a permanent vegetative state, it certainly get´s complicated – my position would be that a human body in a permanent vegetative state (which means that all higher brain functions are irreversibly lost) has no moral worth.

            • Well said Andy. It really is the Sorites Paradox.

            • GEIxBattleRifle

              ”an unconscious person does not have feelings, emotions, desires, or fears at the moment does he not have moral worth?”
              Your forgetting that those unconscious still RETAIN their rationality, theory of mind, autonomy, reasoning abilities etc. If they ”lost” these while unconscious boy would we have a problem when they wake up.

      • I was going to say that the Thomist position suffers exactly the same issues as the OP suggests, but Andreas has pretty much nailed it in the reply!

    • [[An unfertilized egg does have the potential to develop into a human being]]

      So does a strand of hair or a piece of skin. (Using today’s cloning techniques)

      • Andy_Schueler

        So does a strand of hair or a piece of skin. (Using today’s cloning techniques)

        Well….. what you would do there is to extract the nucleus (containing the non-mitochondrial DNA) from a skin cell, and transfer it to an egg (one which had its original nucleus been removed) – so technically, it´s still an egg that´s developing ;-)

    • Richard Edwards

      Really interesting post. As a biologist, I guess I have always had a somewhat unromantic view of the human embryo and would never consider it a “person”. The other big thing for me, which you haven’t mentioned, is other animals. In terms of all the things except *potential* that have been listed, an adult chimp is much more of a “person” than a human baby, let alone a foetus or embryo. I guess that a lot of people who attach special status to a fertilised egg also have trouble accepting that, biologically speaking, we are just animals.

      Reading your post, I was struck by how strange it was that the step from unfertilised to fertilised egg was the moment selected for personhood. I would rate individuality as one condition of personhood and so the moment that the embryo loses the potential to be 2+ individuals would seem to be more of a step change than fertilisation. (To me.) Ultimately, just like most such issues in biology, I would agree that this is a problem of people trying to force binary states onto a continuum.

    • Having just half listened to an abortion debate. It seems the best tack for a pro-lifer is not to argue personhood. Most people understand, as this debate here shows, that personhood is highly subjective and has so many issues as not to be useful foe establish the immorality of abortion.

      So the PL can retreat to a more simple, but ultimately possibly more effective argument:

      An embryo is human life. The taking of this human life by abortion is murder.

      Now, I would not agree with this, but it is a lot more coherent than the notoriously nebulous personhood argument.

    • Pierre Axiaq

      So, when does personhood start? Or, when does a “human life” become a “human person”?

      • Andy_Schueler

        As I mentioned in the post, personhood is something that develops on a continuum – so there never is a transition from “no personhood” to “full personhood”. It is like asking for the precise moment when “night” stops and “day” begins, or asking for the precise moment when “childhood” stops and “adulthood” begins. You can try to come up with pragmatic answers to such questions – like saying that “adulthood” begins when you are 18 years old, but this can never be interpreted as a binary transition (as in: you were 100% a “child” when you were 17 years, 364 days, 23 hours, 59 minutes and 59 seconds old, and exactly one second later you stopped being a child and started being an “adult” 100%).

        • Pierre Axiaq

          Thank you. So if I understand you correctly, there is no real distinction between a “human life” (I am referring to the biologically whole individual of the species) and a “human person”. Upon conception, personhood develops on a continuum. So why isn’t personhood universal for humans? Is it a matter of degree?

          • Andy_Schueler

            Thank you. So if I understand you correctly, there is no real distinction between a “human life” (I am referring to the biologically whole individual of the species) and a “human person”

            There is a distinction, but it is not a binary transition. There is a difference between “day” and “night” and there is a difference between “childhood” and “adulthood” – although in both cases, there never is one discrete moment where one changes into the other, it is rather a gradual process, continuous change.

            Upon conception, personhood develops on a continuum.

            Well, yes and no. I would not agree with picking conception as the starting point of this continuous development. What you define as the starting point is (necessarily) more or less arbitrary, just like it is arbitrary to pick, say, 5:00 AM as the point in time where “night” starts to change into “day” (why not 4:30 AM? Why not 5:19AM?). Conception is a poor choice for a starting point because it is way too early, it would be like defining 0:01 AM as the point in time where “night” starts to change into “day”.

            So why isn’t personhood universal for humans? Is it a matter of degree?

            Yes. And this is something you probably already agree with. You most likely would agree that an unfertilized egg cannot be a human person – an unfertilized egg is however both “alive” and also “human”, so if you believe that an unfertilized egg is not a human person, you also believe that personhood is not a universal attribute of human life.

            • Pierre Axiaq

              I am not sure I understand your last part.

              An unfertilized egg doesn’t have all the information necessary, it is not a biologically whole individual of the species – it lacks half the information. An individual sperm or egg is incapable to become a human being because it lacks the information to do so.

              But once they are united, the distinct diploid cell that is formed has all the information. No human embryology book I have read contested otherwise. The diploid cell is the beginning, a genetically new organism, the primordium some call it, of a human being. I believe this event is called the syngamy and it happens in a very short period of time, within 3 seconds. There is no scientific disagreement about this fact.

              So the question then is, does human personhood also begin at this moment? And if not, then when? And if we do not know, and cannot determine exactly when, are we not potentially killing someone? Then why not play it safe? It is like driving over a man-shaped overcoat in the street, which may be a drunk or may only be an old coat. It is like shooting at a sudden movement in a bush which may be your hunting companion or may be only a pheasant. It is like fumigating an apartment building with a highly toxic chemical not knowing whether everyone is safely evacuated. If later in time, it is established that the victim is a person, then manslaughter or at least criminal negligence has been committed.

              Has any living human person ever skipped this stage during his life?

            • Andy_Schueler

              I am not sure I understand your last part.

              An unfertilized egg doesn’t have all the information necessary, it is not a biologically whole individual of the species – it lacks half the information.

              That is incorrect on several levels:
              1. You assume that during conception, the “information content” within the cell doubles. It doesn´t. You are probably confused here because after conception there are twice as many chromosomes as before – but you have two copies of each chromosome (with one exception – the sex chromosomes – you as a male have just one x chromosome and one y chromosome, but you have two copies of every other chromosome (those two copies are not completely identical, but they are > 99% identical)).
              2. You assume that after conception, the fertilized egg has all the information necessary to develop into an adult human being. It doesn´t, if it would have all this information, you could remove it from the uterus and let it grow in a petri dish, you just would have to feed it – but that doesn´t work, a fertilized human egg requires plenty of factors external to itself (i.e. environmental factors) to grow properly (for example several kinds of hormones that are produced by the mother).
              3. I don´t know what exactly you have in mind when you say “not biologically whole” but I assume you mean that it is somehow “incomplete”. If that is what you mean, then no, it is incorrect to say that an unfertilized egg is “incomplete” while a fertilized egg is “complete” – they are just two different steps in the human reproductive cycle.

              The diploid cell is the beginning, a genetically new organism

              That is indeed true. But also completely irrelevant unless you want to argue that “being human” can be fully reduced to what genes we have. Which would mean that a random liver cell of yours would be a fully human person (because it does have a full complement of 46 human chromosomes) while, say, a woman with Turner syndrome would be less human than you are (because her diploid cells have just 45 chromosomes).
              Have you read my post completely? I address this point in detail – if you try to reduce what it means to be human to the genes we have, you´ll run into absurdities.

              There is no scientific disagreement about this fact.

              This “fact” is this one: “conception is the start of new genetically unique human life”. Note that the unfertilized egg is indeed not genetically unique, but it is both “human” and “alive” (this is why it is false to say that conception is the start of “human life” it is only the start of “genetically unique human life”, the unfertilized egg was just as much “human” and just as much “alive” as the fertilized one is). So, this “fact” is only relevant for the discussion at hand if genetic reductionism is true and “being human” would thus be fully reducible to “what genes do we have”? But genetic reductionism is nonsense.

              So the question then is, does human personhood also begin at this moment? And if not, then when?

              This is what I addressed in my previous answer – your question is not a meaningful one, it is like asking “tell me the exact moment when “night” changes into “day””.

              And if we do not know, and cannot determine exactly when, are we not potentially killing someone? Then why not play it safe?

              We cannot determine an exact moment when our kids turns into “responsible adults” who can be held legally accountable for their actions, have the right to vote, can drive a car, can consent to sex and drink alcohol etc.pp.
              So, should we play it safe and change the legal definition of “adult” from 18 years to, say, 90 years? Or would that be too extreme?

            • Pierre Axiaq

              No, I do not assume that.

              “Almost all higher animals start their lives from a single cell, the fertilized ovum (zygote)… The time of fertilization represents the starting point in the life history, or ontogeny, of the individual.”
              (Carlson, Bruce M. Patten’s Foundations of Embryology. 6th edition. New York: McGraw-Hill, 1996, p. 3)

              “It is the penetration of the ovum by a spermatozoan and resultant mingling of the nuclear material each brings to the union that constitues the culmination of the process of fertilization and marks the initiation of the life of a new individual.”
              (Clark Edward Corliss, Patten’s Human Embryology: Elements of Clinical Development. New York: McGraw Hill, 1976. p. 30.)

              “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)

              “The development of a human begins with fertilization, a process by which the spermatozoon from the male and the oocyte from the female unite to give rise to a new organism, the zygote.”
              (Sadler, T.W. Langman’s Medical Embryology. 7th edition. Baltimore: Williams & Wilkins 1995, p. 3)

              You left the last part of my reply out.

              Any human person can be traced back into his mother womb and back to that particular moment when the person has been conceived. Kill it than, and you have got nothing now, that particular person is gone. Has any living human person ever skipped that stage during his life?

            • Andy_Schueler

              *sigh* Don´t say that you “read embryology textbooks” when in actuality you are copy-pasting the quotes from https://www.princeton.edu/~prolife/articles/embryoquotes2.html .
              Also, none of those quotes contradict what I say in any way, shape or form – an unfertilized human egg is “alive” and “human” what it is not is “genetically unique”, this is what changes during conception. Unless you subscribe to genetic reductionism and plan to argue that “being human” is fully reducible to the genes an organism does (or does not) have, this has no relevance whatsoever.

              Any human person can be traced back into his mother womb and back to that particular moment when the person has been conceived. Kill it than, and you have got nothing now, that particular person is gone. Has any living human person ever skipped that stage during his life?

              Singling out conception here is completely arbitrary. Human development is a continuous cycle and for every moment in this cycle, you could point out “if I would kill this, you would not be here right now”. It works with conception and it works with EVERY developmental step before or after conception. Yes, you would not be here right now if I travelled back in time and killed the fertilized egg that you developed from, but you also wouldn´t be here if I travelled back in time to a moment a few seconds earlier and killed the unfertilized egg that you developed from and you also wouldn´t be here if I travelled back in time to a point a few days after conception and would have prevented the blastocyst that you developed from from implanting into the uterus. Unless you are ready to say that every biological entitity at ANY moment in human reproduction (that includes everything that happens before conception) is a fully human person, this gets you nowhere.

            • Pierre Axiaq

              Of course I read embryology textbooks but I don’t carry then with me everywhere. And thank you for that page, it seems that there are many more that I didn’t know about that confirm this. :)

              You still left the last part of my reply out.

              Any human person can be traced back into his mother’s womb and back to that particular moment when the person has been conceived. Kill it than, and you have got nothing now, that particular person is gone. Has any living human person ever skipped that stage during his life?

              If you think that those texts do not contradict what you said, well, good for you. It was fun. Fortunately, despite our differences you and me made it out and are here to talk about it.

            • Andy_Schueler

              You still left the last part of my reply out.

              Any human person can be traced back into his mother’s womb and back to that particular moment when the person has been conceived. Kill it than, and you have got nothing now, that particular person is gone. Has any living human person ever skipped that stage during his life?

              No, I didn´t leave it out. I quoted it and I addressed it. You or I would not be here if someone would travel back in time and kill the unfertilized eggs that we came from. So, would you therefore conclude that an unfertilized human egg is a human person?

              If you think that those text do contradict what you said, well, good for you.

              So you still think that they contradict anything I have said. And how exactly do they contradict me?

            • Pierre Axiaq

              No, the unfertilized egg alone is not me or you. The unfertilized egg is an unfertilized egg and a sperm is a sperm. But when fertilization occurs, that is me or you, that is the new organism, mine and your unique DNA is formed at that moment, it is different from our mother’s and the father’s, that is the moment when the full complement of our genetic material is
              established, that moment corresponds with the union of sperm
              and egg in conception. From that moment on-wards, that is me or you.

            • Andy_Schueler

              Alright, so you do in fact subscribe to genetic reductionism.
              Then let me ask you two questions:

              1. If I kill you and then use a tissue sample from your corpse to clone you. Would you then agree that the resulting human organism would in fact be you and I would thus not be your murderer (how could I possibly be your murderer if you are alive after all?). If you do not agree, how can you disagree while maintaining what you just said: “your unique DNA is formed at that moment, it is different from our mother’s and the father’s, that is the moment when the full complement of our genetic material is
              established …. From that moment on-wards, that is me or you”?

              2.Would you agree that monozygotic twins are in fact not two persons but rather just one person? If you disagree, how can you disagree while maintaining what you say here: “your unique DNA is formed at that moment, it is different from our mother’s and the father’s, that is the moment when the full complement of our genetic material is established …. From that moment on-wards, that is me or you”?

            • Pierre Axiaq

              I do not subscribe to genetic reductionism.

              You do not have to kill me. I can be alive and you could clone me. Have one of my skin cells removed, and its diploid nucleus (containing all the potential for a new human being) inserted into a female ovum whose nucleus has been removed. If successful, the resulting clone would be genetically my twin, albeit created many years after my own birth. Could one seriously argue that I was not a person prior to the creation of my twin? A small part of my body “split” away to create a new embryo
              (the female ovum was just a passive carrier).
              In a similar way, an embryo that splits is fully a person prior to twinning; a
              second person (also possessing the diploid condition) begins at the moment of the
              split. One of the two resulting embryos (it does not matter which) is ontologically
              continuous with the original fertilized ovum. If human embryos are ever created by
              cloning they would be full human persons. A cloned embryo’s existence would
              begin at the moment equivalent to syngamy (i.e., the moment that the diploid
              order is established) even if such were achieved outside the normal bounds of
              human reproduction.

              Both me and my clone are persons, obviously we are not one and the same person but still persons.

              There is no way to split the “human” from the “person”, something which you are keen to do, but don’t want to at the same time. You say becoming a person is a gradual process but you do not know when it starts – but still you have no problem in killing it.

              But let us reset a bit, how do you define a person? After all, we may be talking nonsense because of the definitions we subscribe to.

            • Andy_Schueler

              I do not subscribe to genetic reductionism.

              Sorry, but this: “your unique DNA is formed at that moment, it is different from our mother’s and the father’s, that is the moment when the full complement of our genetic material is
              established …. From that moment on-wards, that is me or you” simply is genetic reductionism.

              You do not have to kill me. I can be alive and you could clone me. Have one of my skin cells removed, and its diploid nucleus (containing all the potential for a new human being) inserted into a female ovum whose nucleus has been removed. If successful, the resulting clone would be genetically my twin, albeit created many years after my own birth. Could one seriously argue that I was not a person prior to the creation of my twin? A small part of my body “split” away to create a new embryo
              (the female ovum was just a passive carrier).
              In a similar way, an embryo that splits is fully a person prior to twinning; a second person (also possessing the diploid condition) begins at the moment of the split. One of the two resulting embryos (it does not matter which) is ontologically
              continuous with the original fertilized ovum. If human embryos are ever created by cloning they would be full human persons. A cloned embryo’s existence would begin at the moment equivalent to syngamy (i.e., the moment that the diploid order is established) even if such were achieved outside the normal bounds of
              human reproduction.

              Both me and my clone are persons, obviously we are not one and the same person but still persons.

              I highlighted one part in bold. You say “obviously we are not one and the same person”, but given your earlier words, this is actually not obvious at all. You said: “your unique DNA is formed at that moment, it is different from our mother’s and the father’s, that is the moment when the full complement of our genetic material is
              established …. From that moment on-wards, that is me or you” – this would mean that your hypothetical identical twin literally is the same person as you are, you would not be two persons but rather just one. You cannot have your cake and eat it too, these two claims:
              1. your identical twin is not the exact same person as you are (what you say here)
              2. you existed as a human person from the exact moment when your unique set of DNA was created (what you said earlier).
              – cannot simultaneously be true.

              There is no way to split the “human” from the “person”,

              Of course there is. The cells that make up your liver for example are unambiguously “human” but they are also unambiguously not “persons”. Similarly, you already agreed that unfertilized human eggs are not “persons”, they are however absolutely “human”.

              You say becoming a person is a gradual process but you do not know when it starts – but still you have no problem in killing it.

              An three year old child has all properties commonly associated with personhood while human eggs (both fertilized and unfertilized ones) have none of those properties. And a developing human after 12, 20 or 25 or whatever weeks of pregnancy is something in between. I see absolutely no problems with killing a fertilized human egg but I also absolutely do see a problem with late term abortions that happen for no good reason (and I can´t think of any country that actually does allow late term abortions unless the health of the mother is at risk).

              But let us reset a bit, how do you define a person? After all, we may be talking nonsense because of the definitions we subscribe to.

              It´s not really relevant how I define it because my point is a different one – my point is that:
              1. people, including pro-lifers, agree that unfertilized human eggs are not human persons.
              2. nothing changes in the transition from unfertilized to fertilized human egg beyond some biochemistry.
              3. human personhood cannot be reduced to the biochemical processes that happen during the fertilization of a human egg.
              4. Based on 1-3, the fertilized human egg cannot possibly be a human person.

            • Pierre Axiaq

              “2. nothing changes in the transition from unfertilized to fertilized human egg beyond some biochemistry.”

              For fertilization to be accomplished, a mature sperm and a mature human oocyte are needed. Before fertilization, each has only 23 chromosomes. They each possess “human life,” since they are parts of a living human being; but they are not each whole living human beings themselves. They each have only 23 chromosomes, not 46 chromosomes — the number of chromosomes necessary and characteristic for a single individual member of the human species. Furthermore, a sperm can produce only “sperm” proteins and enzymes; an oocyte can produce only “oocyte” proteins and enzymes; neither alone is or can produce a human being with 46 chromosomes.

              A mature sperm and a mature human oocyte cannot singly develop further into human beings. They produce only “gamete” proteins and enzymes. They do not direct their own growth and development. And they are not individuals, i.e., members of the human species. They are only parts–each one a part of a human being. On the other hand, a human being is the immediate product of fertilization. As such he/she is a single-cell embryonic zygote, an organism with 46 chromosomes, the number required of a member of the human species. This human being immediately produces specifically human proteins and enzymes, directs his/her own further growth and development as human, and is a new, genetically unique, newly existing, live human individual.

            • I am not sure if you 100% get that the issue lies in nominalism vs realism. Trying to ascribe an absolute abstract label to a continuum is nigh on impossible unless it becomes arbitrary based on pragmatic use to humans.

              Think the Species Problem, or any issues with assigning laws to ages.

              Eg voting or adulthood. We say that you can vote or become adult when 18. But what happens to an adolescent at the second of midnight when thy become 18 (irrespective of when they were actually born on that day)? What makes them any different to a second before that gives them, now, the characteristics to vote?

              Nothing, of course, We need to arbitrarily segment life to fit into neat categories which are usable for humans. But these demarcations do not actually refer to anything real (ie Platonically so).

              Personhood is a conceptual label which for many intents and purposes has no ontic reality. Hence why no philosopher of theologian can agree on exactly what it entails, what the existence properties are of such a concept.

              You seem to confuse the map for the terrain – the layer of abstraction over reality that we place in order to map it, to describe it. But descriptions are just that.

              They are not reality; the map is not the terrain.

            • Pierre Axiaq

              Exactly, there is no real way to divide them, hence my question of why we arbitrarily choose to kill people at some stage of their life because they are not “persons” or they are, as your friend here put it “something in between”.

            • Andy_Schueler

              So, would you agree then that absolutely nobody should be allowed to vote, drink alcohol, drive a car, consent to sexual activities etc.pp. because we cannot objectively determine a precise moment when someone turns into an “adult”, so we should “play it safe” and consider everyone to be legally a child? Yes or no? And if your answer is “no” – why are you being inconsistent?

            • Pierre Axiaq

              Driving over a man-shaped overcoat in the street, which may be a drunk or may only be an old coat and you kill a person it is manslaughter or at least criminal negligence…that is the law. That is the consistency that should be applied not his nonsense. Equating the life of a person with voting or driving a car….

            • Andy_Schueler

              Ah, so my question is nonsensical but yours isn´t?
              Why?
              Edit: Also, you arbitrarily decide that human life is also a human person after conception, but not before. Why do you think that it is ok to arbitrarily kill pre-conceived people? (and you have killed plenty of pre-conceived people unless you had unprotected sex literally every single time you could have had unprotected sex with someone).

            • You beat me to it!

            • This is fuzzy logic. The take away idea is that personhood is in some way subjective, and in some way does not exist, depending on your philosophy of abstracts,

            • So what you need to do is establish what the existence properties of one stage of development to the next are – what is added – and why this invalidates the action of termination, especially given the permission to terminate the previous stage.

            • Andy_Schueler

              Before fertilization, each has only 23 chromosomes. They each possess “human life,” since they are parts of a living human being; but they are not each whole living human beings themselves. They each have only 23 chromosomes, not 46 chromosomes

              Dude. You subscribe to genetic reductionism, hardcore genetic reductionism, harder-than-hardcore genetic reductionism. Human life is fully reducible to the genes we have and people with genetic abnormalities (e.g. women with Turner syndrome who have just 45 chromosomes in their diploid cells) are less human than you are. This is your position, no matter how much you want to deny it – your words here unambigiously correspond to a position of genetic reductionism and you cannot deny that you subscribe to genetic reductionism without retracting what you say here. You cannot have your cake and eat it too.

              A mature sperm and a mature human oocyte cannot singly develop further into human beings.

              And a fertilized egg also cannot “singly develop further into human beings” because then, it would not need its mother´s uterus.

              They produce only “gamete” proteins and enzymes. They do not direct their own growth and development.

              1. Enzymes are proteins.
              2. There is no such thing as a “gamete protein” – gametes have human genes and synthesize human proteins, the distinction you try to make here has nothing to do with biological reality.
              3. Fertilized eggs do not “direct their own growth and development” any more than unfertilized eggs do. Each step in the human developmental cycle has been adapted to lead to the next step in the human developmental cycle given the right environmental conditions. The distinction you try to make here again has nothing to do with biological reality.

              As such he/she is a single-cell embryonic zygote, an organism with 46 chromosomes, the number required of a member of the human species.

              Dude, do you know how many humans do not have 46 chromosomes? About one in a thousand. Do you think people with Down syndrome are human? If you do, you better retract what you said here, because what you just said means that a person with down syndrome cannot be a member of the human species because you don´t like his genetic makeup.

            • Houston, we have a problem!

    • ignorance_is_curable

      There is a great deal more information that can be added to support various statements made in the main page-article.

      For example, there is the fact that anything that can begin to exist as a result of some purely physical process can also be destroyed by some other purely physical process (like falling into a black hole). It is therefore literally impossible for the ovum-fertilization event to cause an immortal soul to begin to exist. It would need to begin to exist as a result of some other event, perhaps an Act of God.

      Here’s a modified link regarding the natural formation of identical twins, which happens several days after conception: usatoday30 (dot) usatoday (dot) com/news/science/wonderquest/2001-05-09-why-twins-form (dot) htm

      Then there is the topic of “human chimeras”. This type of human starts out as two separate ovum-fertilizations. Each zygote develops separately for a few days, after which two separate blastocysts could implant into the womb and yield fraternal twins. However, sometimes the blastocysts merge to form a single human entity. Often that single human will be quite normal-looking when born, but will have two separate sets of DNA —neither blastocyst died when they merged. But the brain might have one set of DNA, the heart the other set, the kidneys the first set, the gonads the other set, and so on. If you research the topic enough, you will find suggestions that as many as 1/8 of all humans might actually be chimeric. NOW remember that the Standard Religious Claim is that each human has just one soul –so where did the second soul go, when the two blastocysts merged, and neither died?

      Next, there is the topic of “feral children”. All anti-abortion arguments involving the concept of “continuity” or “kind of being” are destroyed by the existence of feral children. That’s because the abortion opponents assume that human biological development alone suffices to yield humans with minds characterized as having abilities like manipulating abstractions rationally, mentally putting oneself into the situation of another, understanding concepts like “good”, “evil”, “the future”, “rights”, and …and so on. WRONG! Pure human biological development alone will always result in a feral child, basically a clever animal, like a chimpanzee or gorilla is a clever animal (but actually somewhat more clever). Various key abilities simply don’t exist, which are associated with distinguishing persons from ordinary animals (abilities that dolphins mostly seem to possess, too, such that some scientists are saying they must be recognized as qualifying as persons, too) In humans it takes very significant Nurturing to to turn a human animal like a feral child into a human person –and if that Nurturing is not provided, feral is all that human will ever be. Here’s a modified link about feral children and human brain development (or lack thereof): prezi (dot) com/j15n2ivfb85w/feral-children-and-the-brain/

      There is a wordpress blog named “fightforsense” that has a large collection of information relevant to the Overall Abortion Debate. Much of it is declared Public Domain and can be copied/posted anywhere.

      • Thanks for your input there. I use the twins poitn in my The Little Book of Unholy Questions chapter on the soul, and I think my free will book (but can’t remember).

      • I have always found feral children interesting and use the development of language, and the vital time frame for development for grammar and language that necessitates important input, without which the agent will never fully graasp such concepts. I talk about this in my free will book. Good stuff – I will check out the fightforsense site – thanks!