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twinning
Abortion - Part 2
In our society at large, most of the "discussion" about abortion takes place without any genuine dialogue or respect. One reason is that both sides of the debate have taken such extreme positions, that people talk past each other, rather than to each other. The end result, is that the only practical point of compromise has been to allow for abortion, (at least as far as federal funding), in cases of rape, incest, or threat to the life of the mother.
I believe that there are truly good people in both camps, and that they are motivated by the best of intentions, desires and beliefs. Nobody can possibly think that abortion is a good thing, even if some believe it is occasionally necessary. Hopefully, we all share a common desire to eliminate the need (perceived or real) for abortion. Toward that end we need to engage a dialogue that is accepting of differing opinions, and tolerant of the people who hold them. We also need minds that are open to change and agreement.
In my last blog, I suggested that "human life" and "human person" are different terms, and I ended with the following question: At what point does the human life that began at conception become a human person with the dignity and rights afforded every other human person? Let us first take a look at the contribution of the biological sciences.
At this stage in the abortion debate, all reasonable people should agree that immediately upon an egg being fertilized by sperm, a life process begins that, if uninterrupted (either artificially or naturally), will result in the birth of a human being. Embryological studies demonstrate that from the moment of fertilization, there is in the zygote a new biological identity that is neither that of the father nor of the mother. We have human life. But is this human life also a human person?
Many of us have met identical (monozygotic) twins at one time or another, perhaps even triplets. Ever wonder where they come from, other than the obvious? They are the result of a process known as twinning, whereby a fertilized egg can split into identical twins or triplets. Although this twinning frequently happens early in the development of the embryo, it can take place up to 14 days after fertilization. It is not commonly known, but the physical similarities between identical twins depends on when the zygote splits. When the split occurs early on, the twins appear less identical, although they still are. The later the split, the more alike the twins appear.
At the same time, gastrulation (the point at which the embryo attaches to the uterine wall and establishes the basic body plan) does not occur until day 21. As a result there are rare circumstances when twinning takes place even after day 14. This usually results in conjoined, or Siamese twins. For the purposes of understanding how twinning contributes to the abortion debate, it is sufficient to use the 14 day period. At that point we have what scientists refer to as individuation. That means that each embryo is a single person.
Of course, identical twins are not an everyday occurrence, with the worldwide estimate being 10 million. Some people might wonder, therefore, why such concern over something as rare as twinning. I would like to suggest that it is more accurate to say that identical twins are an "uncommon" occurrence, and to consider conjoined twins as "rare". After all, it would be disingenuous to dismiss 10 million people from this discussion. Although most zygotes will not separate, we cannot state with any degree of scientific accuracy that we have a unique, individual human person until day 14, since any one of those zygotes may, in fact, become two or three human beings.
Note that, from this scientific approach, viability is not needed to determine individuation and personhood. This, then, sets a firm foundation for a legal position. Since all rights append to individuated persons, not to human life in general, I suggest that the term "human life" in the abortion discussion be replaced with the more accurate and substantial term "human person".
Most of the momentum for opposing abortion arises from religious tradition. These beliefs are profound, often emotional, and grounded in a deep faith in God and what is believed to be God's most precious gift, life. The arguments as I have so far presented them hold up well in the domain of science, but how do they fare with religion? Neither religion nor science can dismiss the other if we are to arrive at understanding and achieve a national consensus on abortion. How can we bring these two differing, but not opposing or competing, disciplines into harmony?
As the old phrase goes, "Stay tuned".
I believe that there are truly good people in both camps, and that they are motivated by the best of intentions, desires and beliefs. Nobody can possibly think that abortion is a good thing, even if some believe it is occasionally necessary. Hopefully, we all share a common desire to eliminate the need (perceived or real) for abortion. Toward that end we need to engage a dialogue that is accepting of differing opinions, and tolerant of the people who hold them. We also need minds that are open to change and agreement.
In my last blog, I suggested that "human life" and "human person" are different terms, and I ended with the following question: At what point does the human life that began at conception become a human person with the dignity and rights afforded every other human person? Let us first take a look at the contribution of the biological sciences.
At this stage in the abortion debate, all reasonable people should agree that immediately upon an egg being fertilized by sperm, a life process begins that, if uninterrupted (either artificially or naturally), will result in the birth of a human being. Embryological studies demonstrate that from the moment of fertilization, there is in the zygote a new biological identity that is neither that of the father nor of the mother. We have human life. But is this human life also a human person?
Many of us have met identical (monozygotic) twins at one time or another, perhaps even triplets. Ever wonder where they come from, other than the obvious? They are the result of a process known as twinning, whereby a fertilized egg can split into identical twins or triplets. Although this twinning frequently happens early in the development of the embryo, it can take place up to 14 days after fertilization. It is not commonly known, but the physical similarities between identical twins depends on when the zygote splits. When the split occurs early on, the twins appear less identical, although they still are. The later the split, the more alike the twins appear.
At the same time, gastrulation (the point at which the embryo attaches to the uterine wall and establishes the basic body plan) does not occur until day 21. As a result there are rare circumstances when twinning takes place even after day 14. This usually results in conjoined, or Siamese twins. For the purposes of understanding how twinning contributes to the abortion debate, it is sufficient to use the 14 day period. At that point we have what scientists refer to as individuation. That means that each embryo is a single person.
Of course, identical twins are not an everyday occurrence, with the worldwide estimate being 10 million. Some people might wonder, therefore, why such concern over something as rare as twinning. I would like to suggest that it is more accurate to say that identical twins are an "uncommon" occurrence, and to consider conjoined twins as "rare". After all, it would be disingenuous to dismiss 10 million people from this discussion. Although most zygotes will not separate, we cannot state with any degree of scientific accuracy that we have a unique, individual human person until day 14, since any one of those zygotes may, in fact, become two or three human beings.
Note that, from this scientific approach, viability is not needed to determine individuation and personhood. This, then, sets a firm foundation for a legal position. Since all rights append to individuated persons, not to human life in general, I suggest that the term "human life" in the abortion discussion be replaced with the more accurate and substantial term "human person".
Most of the momentum for opposing abortion arises from religious tradition. These beliefs are profound, often emotional, and grounded in a deep faith in God and what is believed to be God's most precious gift, life. The arguments as I have so far presented them hold up well in the domain of science, but how do they fare with religion? Neither religion nor science can dismiss the other if we are to arrive at understanding and achieve a national consensus on abortion. How can we bring these two differing, but not opposing or competing, disciplines into harmony?
As the old phrase goes, "Stay tuned".