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The human person and the human brain: some implications of the new science

CHARLES C. CAMOSY

The secular Enlightenment could be described as a “move to the head.”  Late-Medieval Christendom, drawing on the views of Aristotle-inspired scholasticism, understood the human person to be an ensouled animal. The Enlightenment initiated a (gradual) shift toward identifying the human person with capacities of the individual head or brain: self-consciousness, rationality, will, autonomy, etc. The legacy of this tradition in the developed West is so powerful that most aren’t even aware that it could be otherwise. Of course human beings are our brains. What else could be the case?

Identifying persons with brains, however, raises a number of difficult problems. Perhaps the most famous is the mind/body problem—the persistent difficulty in explaining how capacities like consciousness and free will can be reduced to a physical brain without undermining our experience of consciousness and free will.  Not surprisingly, while this was a problem for the Greeks pre-Aristotle, and then again with Descartes and the dawn of the Enlightenment, it was not a major concern for the West in the intervening time.

Then there are the “brain transplant” or “brain splitting” problems—made famous by the philosopher Derek Parfit, who suggested several thought experiments which involve downloading brains into computers and swapping the brains of two people into each other’s bodies. Parfit has also helpfully engaged medical reality—like when surgeons sever the corpus callosum (the main bundle of nerve fibers connecting the left and right hemispheres of the brain) as a treatment for epilepsy. This procedure creates two separate spheres of consciousness housed in each half of the brain—which presents a serious problem for those who want to identify human persons with our brains. If there was one person before the surgery, are there now two persons inhabiting one body? Did the original person die, only to be replaced by two new persons? Were there always two persons in one brain somehow working together?

New scientific discoveries

There are also problems raised by new scientific discoveries. Though it was once uncontroversial to think of consciousness as resulting from “higher” brain functions of the cerebral cortex, we now know this is not the case. Despite having their cortex destroyed, patients like Roger still know who they are, crack jokes, recognize themselves in photographs, and more. Furthermore, we now know that some children born with hydranencephaly (a disorder in which fluid replaces the brain’s cerebral hemispheres) can laugh and cry, understand the difference between familiar people and strangers, and even prefer certain kinds of music. If these children are self-conscious—as they appear to be—then self-consciousness does not require higher brain function.

Some say that we can locate consciousness in the more primitive brain structures, but (in addition to being forced to ask the uncomfortable question about the possible self-consciousness of thousands of non-human species with this primitive brain function) perhaps we should stop and ask why our first instinct is to locate consciousness in the brain in the first place?  Norman Doidge has written extensively about recent revolutions in brain science—and particularly about how brains can change dramatically in attempts to deal with injury and disease—but even he describes this as the brain changing itself.

One of the few to challenge this dogma of the contemporary secular age is the philosopher Alva Noe, who recently wrote a book provocatively titled Out of our Heads: Why You Are Not Your Brain, and Other Lessons from the Biology of Consciousness. Noe directly challenges the scientific establishment, not only on their view that consciousness must be reduced to processes of the brain, but also the idea that science itself will be able to tell us the whole story of consciousness. After providing examples of conscious experiences that cannot be reduced to processes of the brain, Noe concludes that consciousness is not something the brain achieves on its own, but rather the achievement of the whole human animal in her particular environment.

This is precisely the theological understanding of the human person that existed in the West before the secular “move to head.”  Persons are not brains that inhabit a body (or computer!); we are living human animals.

Implications for bioethics

This view has important implications for bioethics. The secular establishment has basically accepted the view that those in a persistent ‘vegetative’ state (PVS) are no longer persons; but this view must now be rethought, not least because we now know that some humans in PVS are self-conscious. The idea that a person dies when her brain dies must also be rethought—along with the idea that humans cannot be persons until a brain is formed. The human animal achieves homeostasis before she has a brain, and can even achieve it when her brain is damaged or dead. The human organism, holistically considered, is responsible for this homeostasis. If we can avoid dogmatic reductions of the human person to the human brain, we are likely to discover that many other features of human existence are the achievement of the whole human animal.

Charles C. Camosy is Assistant Professor of Christian Ethics at Fordham University. Camosy’s research engages with bioethics, Catholic social teaching, moral anthropology, and the intersection of Christian and secular ethics. Camosy is author of Peter Singer and Christian Ethics: Beyond Polarization (Cambridge University Press, 2012), and Too Expensive to Treat?: Finitude, Tragedy, and the Neonatal ICU (Eerdmans, 2010).

{ 3 comments… add one }

  • Jonathan February 13, 2013, 3:30 pm

    Dualism presents its own problems; namely, the problem of causation and a violation of the law of conservation of energy. Saying that higher brain function is not required for some forms of consciousness is not equivalent to saying that the brain is not the primary (if not exclusive) organ of consciousness.

    Parfit “It is interesting that the split-brain studies have not caused more consternation among Non-Reductionists – those who believe that personal identity consists in something over and above facts about the physical brain and body. Many Non-Reductionists believe in the soul, which is often held to be created by God, indestructible, and indivisible. What would a believer in immortal souls say about split-brain surgery? That the surgeon’s knife divides a soul, creating two from one? Or that a single soul can have two centres of consciousness?”

    Is there a pre-Enlightenment anthropology that can account for this?

    Interesting post.

  • Charlie February 14, 2013, 11:42 am

    Hi Jonathan…thanks for the comment. I must admit that I haven’t thought about this enough to have thought through all the implications of what I’m about to say, and I even find myself hesitating to say it because I am a child of the post-Enlightenment world, but perhaps it shouldn’t be so strange to think of a human organism having multiple centers of consciousness. Students of psychology have told us for some time now that even for non-injured people there are multiple “selves” operating at the same time. It is also true that over time, though I remain the same human animal, I have very different centers of consciousness at one point vs. at another point.

    Anyway, the kind of soul to which I’m committed is not the kind of dualist-inspired soul described in your quote from Parfit. The soul, in my view, is just the form of the particular human animal.

  • William Branch February 15, 2013, 6:53 am

    Ancient Egyptians didn’t have such a stilted view of psychology (study of the soul, not the mind). A person had several souls, including a “ba” and a “ka”. What distinguished a divinity from a human included having more than one of each of these soul-components. Similarly the Kabbalists divided both human and divine into ten “sephirot”.

    A larger problem is the metaphysics of subjectivity vs objectivity. Both quantum mechanics and Mahayana Buddhism face this conundrum. The case of quantum mechanics is illustrative. An electron is neither a particle nor a wave … but that the observer is inseparable from that is observed, and if the observer’s technique is more “particulate”, then the observed electron behaves as a particle, but if the observer’t technique is more “wavy”, then the observed electron behaves as a wave.

    Perhaps the greatest problem are the Platonic and Aristotelian shibboleths that dominate Western theology. Most Western people, not just theologians, view objectivity as a question of the intellect using rationality and observation to discover the unique Forms … rationality being emphasized by Plato and observation being emphasized by Aristotle.

    Unconscious assumptions bind with invisible bonds, every intellectual endeavor, as do conscious dogmas (our existing organum of what we think we know to be true).