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Personhood & Abortion Rights:
How Science Might Inform this Contentious Issue

Although it has been 45 years since Roe v. Wade was decided by the Supreme Court of the United States (SCOTUS), abortion continues to be a highly controversial and polarizing issue within the body politic. At the two ends of the continuum are the radical pro-life and radical pro-choice advocates. The radical pro-life position is that from the moment of conception the human organism is a person that should have full human rights, including the right to life, and these rights should be fiercely protected by the state. On the other side, the radical pro-choice position is that the pregnant woman already has full human rights, including the right to bodily autonomy, and that she can freely decide to end her pregnancy at any time she wishes for any reason at all. Many pro-lifers view the zygote—the one-celled human organism resulting from fertilization—as sacred, and believe that causing the death of the zygote, embryo, or fetus, either directly or indirectly, is murder. By contrast, the pro-choicers believe that the organism becomes a person only after it leaves the womb and becomes disconnected from the life support of the mother. The main purpose of this essay is to articulate a third position that falls between these two extremes. Call it the “pro-person” position. Although it leans more towards the pro-choice stance, it has a much stronger philosophical and scientific foundation.

Most of us would agree that all persons should be assigned the full spectrum of human rights, e.g. rights to life, bodily autonomy, property, etc. But what is a person anyway? When does the human organism developing inside a woman become a person? Traditionally, the answer was left to theologians and religious leaders. The prevailing view during the time of Aristotle was that the human soul entered the forming body at 40 days in male embryos and at 90 days in female embryos.1 On the other hand, during medieval times theologians referencing Genesis concluded that the soul enters the body when the baby takes its first breath. Today, many religious people opine that “ensoulment” occurs at fertilization. As efforts to define, identify, or locate the soul have failed, and as religion has declined in its influence, different thinkers have simply pinned the beginning of personhood to different developmental milestones.

The most popular milestones have included: conception, first heart beat, quickening (fetal movement when first detected by the pregnant woman), onset of pain perception, first brain waves, first brain waves in the cerebral cortex, birth itself, and first breath. On May 4, 2018, the governor of Iowa signed into law a bill which bans most abortions once a fetal heartbeat is detected, occurring usually around six weeks of pregnancy.2 On the other hand, the decision in Roe v. Wade in 1973 accorded importance to fetal viability, but this has obvious drawbacks. Viability depends very much on modern medical technology and the skill of physicians and nurses. With the best of technology, a 20-week-old fetus may occasionally be kept alive, but without it even a 36-week-old fetus may perish. In the future it will probably become possible to sustain a human organism in a special artificial incubator from fertilization for a period of nine months, making viability a moot point. Personhood should not be defined by the fetus’ location, dependence, or connection to another human or to machines. Personhood should be defined by … the species and the current capacities of the fetus.

Standard dictionary definitions of “person” are simplistic. Two relevant ones from Merriam-Webster are “human, individual” and “one (such as a human being, a partnership, or a corporation) that is recognized by law as the subject of rights and duties.”3 Three from are “a human being, whether an adult or child,” “a self-conscious or rational being,” and “the body of a living human being.”4 And finally, the Oxford Living Dictionary defines a person as “a human being regarded as an individual.”5 Wikipedia provides more depth, defining “person” as “a being that has certain capacities or attributes such as reason, morality, consciousness or self-consciousness, and being a part of a culturally established form of social relations such as kinship, ownership of property, or legal responsibility,” adding that the “defining features of personhood and consequently what makes a person count as a person differ widely among cultures and contexts.”6

Traditional and Cultural vs. Scientific Developmental Milestones

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“What is a person?” is a deep and important philosophical question. When most of us think of a person we think of “the man or woman on the street,” i.e. a human being who is conscious, senses, thinks, feels, behaves, has preferences and values, remembers, learns, makes decisions, communicates, and interacts. Let’s call this paradigm of personhood “the human adult.” And yet, most of us also think that this paradigm does not go far enough. We believe babies and children are persons too. This is probably because they have the rudimentary cognitive capacities that are developed to their greatest extent in the human adult. At the same time, however, we have learned from the biological sciences that the human zygote has none of these cognitive capacities. And so, sometime between fertilization and natural birth the developing human organism acquires a set of basic cognitive capacities that will eventually distinguish it as a human adult from its nearest genetic relative—the chimpanzee. There is one of these cognitive capacities that is easy to understand and appreciate, upon which the others probably depend, and which can serve as our marker of personhood. This is the capacity for consciousness.

We all have an intuitive grasp of consciousness. When we are asleep at night and not dreaming, we are unconscious, and when we wake up in the morning we are conscious. When we are unconscious, we don’t know that anything is happening, but when we are conscious we know that something is happening. William James, known as America’s first psychologist, conceived of consciousness as a stream of experience.7 Now, with this useful intuition, imagine that there was a time when you were in the womb and your brain was so immature that it could not enable consciousness. You had never before been conscious! Now further imagine that your brain, especially your cerebral cortex and thalamus, became large, complex, connected, and structured enough that it enabled consciousness for the first time. Let’s call this event “the onset of consciousness” in the individual human organism. Yes, it was probably a fuzzy or amorphous experience in one or more modalities (hearing, sight, touch, pain, etc.), but nevertheless the “lights were finally on in the house.” I contend that at this time in the 21st century the best answer to the philosophical question “What is a person?” is “any human organism with the current capacity for consciousness.”

A human organism is not a person when it has never before or will never again possess the capacity for consciousness.

An obvious retort to this idea is “That would mean that whenever we go to sleep, we are not persons, but whenever we awaken, we are persons.” This challenge fails to recognize the difference between the capacity for and the state of consciousness. Not until the organism is conscious for the first time may we conclude that it has the capacity for consciousness. After that, the capacity perseveres because it is tied to underlying brain processes, as we shall see later. And so, the sleeping human organism has the capacity for consciousness and is still a person. A related challenge is “That would mean that a person in an extended coma is not a person, and this entails a contradiction.” By the definition I have presented the person who permanently loses the capacity for consciousness would become a human who is not a person. He or she would lack the same defining property of personhood that they lacked earlier as a zygote, embryo, or fetus. These considerations lead to a general principle of “Never Before or Never Again.” This means that a human organism is not a person when it has never before or will never again possess the capacity for consciousness.

Another objection to my definition is that the onset of consciousness must be a process, not a discrete event—a dimmer knob instead of an on-off light switch. This could be, but I doubt it, and if so, it matters little. For now we may just assume that the onset of consciousness is similar to waking up in the morning. There is that first moment when we just know we are aware and are experiencing the world.

Now that we have answered the philosophical question “What is a person?” we may move on to the scientific question of “When in the course of development does the human organism acquire the capacity for consciousness?” One of the most important scientific discoveries of the last 400 years, right up there with the discoveries of the laws of motion, evolution, DNA, and relativity, is the discovery of the dependence of experience and cognitive functions on brain structure. Speaking cautiously by calling it an “astonishing hypothesis” in book title form, Francis Crick, the co-discoverer of DNA, proposed that “You, your joys and your sorrows, your memories and your ambitions, your sense of personal identity and free will, are in fact no more than the behaviour of a vast assembly of nerve cells and their associated molecules.”8 Over and over this hypothesis has been supported by thousands of scientific studies, and there appear to be no disconfirmations of it. And so, the onset of consciousness must depend on or be tied to brain structures and processes. This finding forms part of the naturalistic or materialist view of the world. Even dualists and idealists admit that the brain is absolutely necessary for the mind to function.

So, when does the onset of consciousness occur in the fetus with respect to conception? In the Roe v. Wade decision of 1973, writing for the majority, Justice Harry Blackmun wrote, “We need not resolve the difficult question of when life begins. When those trained in the respective disciplines of medicine, philosophy, and theology are unable to arrive at any consensus, the judiciary, at this point in the development of man’s knowledge, is not in a position to speculate.”9 The problem here is that Blackmun and his SCOTUS colleagues were addressing the wrong question— “When does life begin?” Depending on perspective, there were two correct answers to that question that were already known in 1973. Life on the Earth began 3.5 billion years ago. The life of a unique human organism, however, does begin at conception. But the right question for the SCOTUS would have been, “When does the human fetus become a person?” Or as we have defined it here, “When does the human fetus acquire the capacity for consciousness?” Perhaps in 1973 there was not a consensus on that question, but now experts in medicine, biology, neuroscience, and philosophy are honing in on the answer. I will first cite the findings and opinions of experts in fetal development of the brain and then tie these together to reach general conclusions.

Feeling pain is clearly one aspect of consciousness, and the onset of pain may be viewed as a proxy for the more general onset of consciousness. In a 1987 article in the New England Journal of Medicine, K.J.S. Anand and P.R. Hickey summarized findings linking brain structure and pain perception in fetuses and neonates.10 “The timing of the thalamocortical connection is of crucial importance for cortical perception, since most sensory pathways to the neocortex have synapses in the thalamus. Studies of primate and human fetuses have shown that afferent neurons in the thalamus produce axons that arrive in the cerebrum before mid-gestation. These fibers then ‘wait’ just below the neocortex until migration and dendritic arborization of cortical neurons are complete and finally establish synaptic connections between 20 and 24 weeks of gestation.” They continue, pinpointing when, precisely, these neural connections are made:

Functional maturity of the cerebral cortex is suggested by fetal and a neonatal electroencephalographic patterns, studies of cerebral metabolism, and the behavioral development of neonates. First, intermittent electroencephalographic bursts in both cerebral hemispheres are first seen at 20 weeks gestation; they become sustained at 22 weeks and bilaterally synchronous at 26 to 27 weeks. By 30 weeks, the distinction between wakefulness and sleep can be made on the basis of electroencephalo-graphic patterns. Cortical components of visual and auditory evoked potentials have been recorded in preterm babies (born earlier than 30 weeks of gestation), whereas olfactory and tactile stimuli may also cause detectable changes in electroencephalograms of neonates. Second, in vivo measurements of cerebral glucose utilization have shown that maximal metabolic activity in located in sensory areas of the brain in neonates (the sensorimotor cortex, thalamus, and mid brain- brain-stem regions), further suggesting the functional maturity of these regions. Third, several forms of behavior imply cortical function during fetal life. Well-defined periods of quiet sleep, active sleep, and wakefulness occur in utero beginning at 28 weeks of gestation.

Several years later in 1998, D. Gareth Jones from New Zealand summarized relevant findings in his article in the Journal of Medical Ethics.11 “Gertler had proposed 22–24 weeks gestation for ‘brain birth’ on the basis that the neocortex begins producing EEG waves at this time.” “In similar fashion, Burgess and Tawia defined a functioning brain as one where there is identifiable activity of the kind that normal adult brains (cortices) indulge in. They argue that what is required is a critical minimum level of structural organisation, with functional components present and mature enough to perform. On the basis of EEG readings, they conclude that a fetus becomes conscious at 32–36 weeks gestation.” “Also relevant here is the issue of fetal awareness, which has been placed at not earlier than 26 weeks gestation by a 1997 working party of the Royal College of Obstetricians and Gynaecologists.”

In a paper sponsored by the Markulla Center of Applied Ethics in 2001, Dr. David L. Perry stated “Partly because of the ambiguity of fetal EEG patterns, it’s difficult to say precisely when consciousness first occurs. But somewhere between 20 and 32 weeks gestation, the cortical neurons become capable of firing in ways that make consciousness possible. The brainstem and nervous system may function before that time, and there may be reflex reactions to stimuli, but there is no one ‘there’ yet to experience sensory inputs—the lights are on, but nobody’s home.”12

In a 2010 newspaper article health reporter Megan Ogilvie nicely summarized much of the scientific work on the onset of consciousness: “What is known is that consciousness cannot occur until the peripheral nervous system joins up with the cerebral cortex, the region of the brain responsible for memory, awareness and language. That connection between the sensory receptors—what allows us to sense the outside world—and the higher brain doesn’t fully occur until about the 26th to 28th weeks of gestation.”13

Again, focusing on pain perception in their 2005 article in the Journal of the American Medical Association, Lee, Ralston, and Drey concluded: “Pain is an emotional and psychological experience that requires conscious recognition of a noxious stimulus. Consequently, the capacity for conscious perception of pain can arise only after thalamocortical pathways begin to function, which may occur in the third trimester around 29 to 30 weeks’ gestational age, based on the limited data available.”14

Christof Koch, one of the world’s leading neuroscientists who worked for many years with the late Francis Crick, has said “But when does the magical journey of consciousness begin? Consciousness requires a sophisticated network of highly interconnected components, nerve cells. Its physical substrate, the thalamo-cortical complex that provides consciousness with its highly elaborate content, begins to be in place between the 24th and 28th week of gestation. Roughly two months later synchrony of the electroencephalographic (EEG) rhythm across both cortical hemispheres signals the onset of global neuronal integration. Thus, many of the circuit elements necessary for consciousness are in place by the third trimester.”15

A comprehensive review of the relevant scientific literature remains to be done. However, based on the evidence presented here, general conclusions may be reached. The best estimate for the onset of consciousness in the fetus (especially the beginning of pain perception) is at 27 weeks gestational age, which is roughly 25 weeks from conception. (Gestational age is defined as the number of weeks since the beginning of the pregnant woman’s last menstrual cycle. The actual age of the embryo will be less than gestational age.) Greater precision in specification of the onset of consciousness is likely to be achieved with advances in neuroscientific theory and methods. Functional magnetic resonance imagery (fMRI) of the developing fetus will undoubtedly play a great role in the next decade.

Although the available scientific evidence does not yet enable a precise answer to our question “When does the human fetus acquire the capacity for consciousness?” we have an adequate answer for now. The formulation of moral rules and laws cannot wait on a final answer from science, if there is such a thing as a final answer. Blackmun and the SCOTUS realized this in 1973 when they laid out the shaky trimester plan that depended so heavily on the concept of viability of the fetus. But since the early 1970s religion has withered, philosophy and science have advanced, and we are now at a point when we can do much better. A valid personhood amendment today would go something like this:

For purposes of this Constitution and relevant laws, a ‘person’ shall be construed to be any human organism that has the current capacity for consciousness. Based on the best available scientific research and theory, the beginning of personhood in the human fetus shall be construed as the start of the 25th week post conception. Furthermore, the end of personhood shall be construed as the permanent loss of the capacity for consciousness in any particular human organism. This amendment should be reconsidered and updated with advances in science after 25 years.

Human organisms are unique, and surely they do not all become persons at the same time since their conceptions. They are not robots designed to unfold on an invariant schedule. Imagine a graph that accurately describes brain development with respect to consciousness for a sample of a thousand human fetuses. On the X-axis is plotted time in weeks since conception (considered at the end of each week), and on the Y-axis is plotted the percentage of fetuses in the sample that have acquired the capacity for consciousness. The graph is likely to resemble an S-shaped curve. It is reasonable to expect data points at zero percent on the Y-axis for the weeks 1–24, marks at one hundred percent on the Yaxis for weeks 28–39, and marks at intermediate percentages at weeks 25, 26, and 27. Drawing a vertical “personhood line” at the 24th week since conception, such that fetuses before then are classified as nonpersons and fetuses after then are classified as persons, is a conservative approach designed to minimize false negatives, i.e. the classification of a particular fetus as a nonperson when it is really a person, which could lead to aborting a fetus “too early.” In this approach doctors could use “the fetus is at least 25 weeks old” as a proxy for “the fetus has acquired the capacity for consciousness and is now considered a person.” And doctors should be able to make sound estimates of the age of the fetus based on physical tests, scans, and interviews of the pregnant woman.

The philosophical and scientific foundation for the pro-person position is now secured. Both the prolife and pro-choice positions are misguided. The zygote, embryo, nor early fetus are persons as here defined, as the pro-lifers have suggested. But contrary to the pro-choicers, the late fetus is indeed a person. In alignment with this new pro-person position I suggest these moral principles and cultural changes:

  1. No human rights, including a right to life, should be assigned to the human organism during development before it becomes a person. And so, a woman should be able to remove or kill the zygote, embryo, or fetus inside her before it becomes a person for any reason at all without penalty to her or to others who help her.
  2. Human rights, including a right to life, should be assigned to the human organism during development when it becomes a person. And so, a woman should not be permitted to remove or kill the fetus inside her after it becomes a person without penalty to her or her helpers, unless she has a very good reason that could only be that continuing the pregnancy would pose significant risk of permanent harm or death to her.
  3. Abortions should be provided only by licensed medical practitioners under safe conditions.
  4. It should be against the law for a woman to perform a self-abortion, get an abortion from an unlicensed practitioner, or to get a late abortion for any reason other than the very good reason specified above, or for any other person to cooperate in or enable these acts. No person should have a right to privacy to commit illegal acts, even if the act happens to be an illegal abortion.
  5. A violation of abortion laws should carry a penalty of one year and one day in jail. This would make the crime a felony.
  6. Legal abortion should be accessible, free, quick, private, and safe.
  7. Gradually cultural changes can and should be made to reflect the new understanding of personhood. Only after their fetuses become persons, parents should name their fetuses, and should talk, read, and sing to their fetuses. Perhaps eventually, birth certificates can be replaced by personhood certificates, with citizenship in the country established at date of personhood.

The pro-person position, as I have outlined it in this essay, recognizes the late fetus and the host woman both as persons with human rights. When these rights come into conflict, as can occur during the last 15 weeks of pregnancy, then the state must intervene through a clear constitution, laws, and/or policies to resolve the conflict. The pro-person position provides a specific path for resolution. The prolife position has been mistaken from the start. It is indefensible to invoke a magical “ensoulment” and to thereby classify the zygote as a person. While more reasonable, the pro-choice position is also off the mark. It has relied on obsolete notions such as trimesters, viability, and privacy implied in or lifted from Roe v. Wade and the premise that a fully conscious fetus is not a person. On the other hand, the pro-person position corrects all these errors and is based on a solid philosophical and scientific foundation, which can still change as new evidence, reasons, and arguments are brought forth. In summary, the core idea of the pro-person position is that the human organism becomes a human person when it acquires the capacity for consciousness at approximately 25 weeks after conception. END

About the Author

Dr. Gary Whittenberger Ph.D. is a free-lance writer and retired psychologist, living in Tallahassee, Florida. He received his doctoral degree in clinical psychology from Florida State University after which he worked for 23 years as a psychologist in prisons. He has published articles on science, philosophy, psychology, and religion, and he is a member of several freethought organizations. He is the author of two books: God Wants You to be an Atheist: The Startling Conclusion from a Rational Analysis and God and Natural Disasters: A Debate Between an Atheist and a Christian.

  1. Wikipedia. “Ensoulment.”
  2. CBS News. 2018. “Iowa abortion bill signed into law by Gov. Kim Reynolds.” 4 May.
  3. Merriam-Webster. “Person.”
  4. “Person.”
  5. Oxford Living Dictionary. “Person.”
  6. Wikipedia. “Person.”Web.17 May 2018.
  7. Carreira, Jeff. 2013. “William James, The Stream of Consciousness and Freewill.” Philosophy is Not a Luxury. 21 March.
  8. Crick, Francis. 1995. The Astonishing Hypothesis: The Scientific Search for the Soul. New York: Scribner.
  9. Blackmun, Harry. 1973.
  10. Anand, K.J.S., and Hickey, P.R. 1987. “Pain and its Effects in the Human Neonate and Fetus.” The New England Journal of Medicine. Vol. 317, No. 21: 1321–1329.
  11. Jones, D. Gareth. 1998. “The problematic symmetry between brain birth and brain death.” Journal of Medical Ethics. Vol. 24: 237–242.
  12. Perry, David L. 2001. “Ethics and Personhood: Some Issues in Contemporary Neurological Science and Technology.” Markulla Center of Applied Ethics: Better Choices. 11 December.
  13. Ogilvie, Megan. 2010. “The Life of the Brain: Beginnings.” The Star. 9 July. Toronto Star Newspapers Ltd.
  14. Lee, Susan J., Ralston, Henry J. Peter, and Drey, Eleanor A. 2005. “Fetal Pain: A Systematic Multidisciplinary Review of the Evidence.” Journal of the American Medical Association. Vol. 294(8): 947–954.
  15. Koch, Christof. 2009. “When Does Consciousness Arise in Human Babies? Does sentience appear in the womb, at birth or during early childhood?” Scientific American Mind. 31 August.

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