Michael R. Egnor is a practising neurosurgeon – not a philosopher speculating about the brain, but a man who has operated inside brains for four decades. Professor of Neurosurgery and Pediatrics at Stony Brook University (New York), longtime director of pediatric neurosurgery, and by his publisher’s account the surgeon of some 7,000 brain operations. And it is precisely this man who says: the brain does not explain the mind. Egnor began as a convinced materialist and atheist; today he holds an Aristotelian-Thomistic dualism and argues that intellect and will are immaterial. His book The Immortal Mind. A Neurosurgeon’s Case for the Existence of the Soul (with the science writer Denyse O’Leary, Worthy/Hachette, June 2025) makes this case from surgical practice. That Egnor is at the same time a Senior Fellow of the Discovery Institute – the centre of the Intelligent Design movement – belongs to an honest account and is stated openly in this article.
Who is Michael Egnor?
Born in 1954, raised in a secular environment not hostile to religion. Medical degree (M.D.) from the College of Physicians and Surgeons of Columbia University in New York, neurosurgical residency at Jackson Memorial Hospital in Miami. At Stony Brook University since the 1990s, where he is Professor of Neurosurgery and Pediatrics and served for years as director of pediatric neurosurgery. His clinical focus is pediatric neurosurgery, in particular hydrocephalus and the dynamics of cerebrospinal fluid.
This matters because it gives Egnor’s argument its substance: he is scientifically published (among others in the Journal of Neurosurgery, in Pediatrics and in Cerebrospinal Fluid Research) and an award-winning operating surgeon. Whoever debates him debates not an outsider without a field, but an established clinician who advances an uncomfortable philosophical position from the operating room.
From materialist to dualist
Egnor describes his own path as a reversal: as a young biochemistry student at Columbia he was a convinced materialist – the brain was to him the key to everything a human being is. Doubt came first not from religion but from science itself: he found the Darwinian account of complex biochemical pathways to be, in his words, "sketchy science" compared with the rigour of physics and chemistry. This early scepticism later drew him into the Intelligent Design milieu – a step that is highly contested scientifically and that we place in context below.
The second source of his turn was the clinic. Again and again he encountered patients with massive brain deficits who nevertheless functioned normally. And a personal crisis – early worry about autism in his youngest son – led Egnor, by his own account, to conversion to the Catholic faith. These biographical details come from his own interviews and essays; they explain his motivation but replace no argument. The load-bearing arguments are clinical.
The case of Katie
Egnor’s most frequently told case is that of a twin girl he describes in his essay Science and the Soul (Plough Quarterly) and in the book. Katie was born with severe hydrocephalus; on the scans her head was "mostly empty" – only a thin rim of brain tissue at the edge and a remnant at the base of the skull, the rest fluid. She had, Egnor says, about a third of the brain mass of her healthy twin sister.
By textbook expectation Katie should scarcely have been viable. In fact, according to Egnor’s report, she developed excellently: she sat, spoke and walked earlier than her sister, made her school’s honour roll and was close to graduating high school. Egnor’s conclusion in the essay – and it should be read as his interpretation, not as a proven proposition – is: "Katie, like you and me, has a soul." He cites further similar cases, including a young woman born missing about two-thirds of her brain who lives as a wholly normal adult.
What the case shows and what it does not must be kept apart. It shows impressively the plasticity of the early-childhood brain and how poorly crude volume measures predict mental performance. Whether beyond this it demonstrates an immaterial soul is Egnor’s philosophical interpretation – one that can be disputed, and that critics do dispute.
Wilder Penfield and the 1,100 awake surgeries
Egnor repeatedly invokes Wilder Penfield (1891–1976), the Canadian founder of modern epilepsy surgery at the Montreal Neurological Institute. Penfield operated on the awake brain for over 40 years, electrically stimulating the exposed cortex of some 1,100 patients to map speech and movement areas. He could evoke movements, sensations, fragments of memory and emotions.
Penfield’s own conclusion, drawn in his last book The Mystery of the Mind (1975), is the point: he began a materialist and ended convinced that cortical stimulation can trigger contents of consciousness but never the thinking, deciding mind itself. No stimulus, Penfield reported, made a patient believe or decide; one could make the arm rise, but not generate the will to raise it. Egnor cites Penfield as a first-hand witness – and unlike many second-hand appeals, Penfield’s dualist turn is well documented.
The seizure argument
Egnor’s most original and sharply formulated argument comes from his own epilepsy surgery. An epileptic seizure is a disordered electrical discharge in the cortex. When the patient remains conscious, seizures can produce muscle movements, perceptions, memories and emotions. What they never produce, says Egnor: abstract thought.
There is, in his words, no "arithmetic seizure", no "philosophy seizure", no "morality seizure". No one has ever had a seizure in which they involuntarily solved an equation, reflected on justice, or formed a logical argument. Egnor’s inference: if abstract thought – concepts, logic, moral judgment – were purely material-neuronal, a disordered discharge ought occasionally to trigger it, just as it triggers movement and memory. That it never does is for him an empirical sign that intellect and will do not arise from the cortex. This is an argument from absence – not a compelling proof, but a clinically well-grounded objection that deserves to be taken seriously.
Split-brain: a person remains one person
The third building block is the split-brain patients. In severe epilepsy the corpus callosum, which connects the two cerebral hemispheres, used to be severed. The neuropsychologist Roger Sperry (Nobel Prize in Medicine 1981) studied these patients and found in the laboratory remarkable half-separations of perception – but in ordinary life, Sperry said, each patient remained one person with one will and one coherent self.
Egnor reads this as follows: one can physically halve the brain without halving the person. Intellect and will – the capacity for abstract thought and choice – remain undivided even though the material bridge between the hemispheres is gone. Here too caution applies: the split-brain interpretation is contested in neuropsychology, and there are counter-readings (for instance by Michael Gazzaniga) that see a subtler splitting. Egnor’s point is the everyday unity of the person, not the laboratory findings in detail.
Aristotelian, not Cartesian
A common misunderstanding: Egnor is not a Cartesian dualist. He explicitly rejects Descartes’ picture of the mind as a separate "substance in the machine-body". His position is hylomorphic dualism in the tradition of Aristotle and Thomas Aquinas, as advanced today by, for instance, the philosopher Edward Feser: the soul is not a ghost in the brain but the form of the living human being. Material faculties (senses, movement, memory) are bound to organs – Egnor does not deny this. Immaterial, for him, are only the specifically intellectual faculties: the grasp of abstract, universal concepts and free will.
This distinction is decisive because it sidesteps many standard objections to dualism. Egnor need not deny that brain damage alters personality, speech or memory – his theory even expects it. His claim is narrower and thereby harder to refute: that conceptual understanding and freedom of the will in particular are not materially localisable.
The Immortal Mind (2025)
In June 2025 Egnor’s book The Immortal Mind. A Neurosurgeon’s Case for the Existence of the Soul appeared, written with Denyse O’Leary (Worthy Publishing, Hachette group). It gathers the clinical cases – hydrocephalus patients with little brain, the Penfield findings, the seizure observation, split-brain – and adds a chapter on near-death experiences. The line of argument runs throughout: the brain is the condition of mental life but not its complete producer.
With this Egnor stands in a line with a series of scientists we have already portrayed here – most directly with the Nobel-laureate neurophysiologist John Eccles, a lifelong dualist who in 1992 even published a quantum-mechanical mind-brain model. Federico Faggin and the near-death researchers Bruce Greyson and Eben Alexander likewise argue that consciousness is not exhausted by the brain. Egnor adds operative neurosurgery to this series – the discipline that comes closest to the brain itself.
The criticism – stated honestly
Egnor is a contested figure, and for understandable reasons. Whoever cites him should know the objections:
- Discovery Institute and Intelligent Design. Egnor has written since 2007 for the ID-aligned blog Evolution News and is a Senior Fellow of the Discovery Institute; he signed the statement A Scientific Dissent from Darwinism and appeared in the 2008 film Expelled. Intelligent Design is not regarded as science by established biology. This affiliation is the most frequent and weightiest reservation against him – it colours the reception of his neurological arguments, even though the two topics are logically separate.
- "God of the gaps". The neurologist and sceptic Steven Novella charges Egnor with inferring too hastily from present explanatory gaps in brain research to an immaterial soul – a god of the gaps. Where Egnor says "the brain does not explain it", Novella says "the brain does not explain it yet".
- Evolutionary biology. The biologist Jerry Coyne calls Egnor’s statements on evolution "decades out of date".
- The cases as interpretation. Even sympathetic readers stress: hydrocephalus cases like Katie show brain plasticity, not necessarily a soul; the seizure argument is an argument from absence; the split-brain reading is contested. Egnor’s observations are strong, his metaphysical conclusion remains a conclusion.
The fair reading separates the two cleanly: Egnor’s first-hand clinical observations are valuable and are rarely disputed even by opponents. His worldview conclusions – soul, immortality, Intelligent Design – are interpretations that can and must be argued over. Anyone invoking Egnor as a witness should keep this boundary rather than blur it.
What remains
- A clinician, not a speculator. Egnor’s arguments come from the operating room, not the armchair. That gives them a weight purely philosophical dualism arguments lack – and at the same time does not make them compelling.
- The strongest observation is the absence. That seizures trigger movement, perception, memory and feeling but never abstract thought is an empirically testable, clinically well-grounded finding. It does not refute materialism, but it is a serious challenge to it.
- The interpretation must be kept open. Plasticity rather than soul, "not yet" rather than "not" – the materialist counter-readings are legitimate. As with the question whether the brain produces consciousness or merely transmits it, the proof lies on neither side. More on this in our article Consciousness and the Brain: a Conjecture, Not a Proof.
- The affiliation belongs in the account. Egnor’s closeness to the Discovery Institute is real and must be named. It does not automatically invalidate his neurosurgical observations – but it explains why his work polarises.
- Context. Egnor joins a documented line: Eccles, Faggin, the near-death research around Greyson. On the institutional background of why such positions are marginalised in the scientific establishment, see Mediumship and Power.
Sources
- Michael Egnor & Denyse O’Leary: The Immortal Mind. A Neurosurgeon’s Case for the Existence of the Soul. Worthy Publishing (Hachette), New York 2025. ISBN 978-1-5460-0635-0.
- Michael Egnor: Science and the Soul. Essay, Plough Quarterly – with the case of Katie.
- Wilder Penfield: The Mystery of the Mind. A Critical Study of Consciousness and the Human Brain. Princeton University Press 1975 – the 1,100 awake surgeries and Penfield’s dualist turn.
- Roger W. Sperry: work on cerebral commissurotomy (split-brain), Nobel Lecture 1981.
- Michael Egnor: contributions to Evolution News (Discovery Institute) and Mind Matters, among others on the seizure argument and "forced thinking".
- Stony Brook University: faculty profile of Michael R. Egnor, Department of Neurosurgery.
- Steven Novella: NeuroLogica Blog – the "god of the gaps" critique of Egnor.
- Edward Feser: Philosophy of Mind. A Beginner’s Guide and Aquinas – on the hylomorphic (Aristotelian-Thomistic) dualism Egnor invokes.