Michael Egnor and Denise O’Leary, The Immortal Mind: A Neurosurgeon’s Case for the Existence of the Soul.
Hachette Nashville, 2025.
ISBN 978-1-5460-0637-4 (ePub).
In The Immortal Mind, neurosurgeon Michael Egnor offers a thoughtful analysis regarding one of the most fundamental questions in bioethics: “What is this thing we call consciousness?” The answer to that question is fundamental to a related question, “What does it mean to be human?” Drawing on forty years of clinical practice, Egnor and O’Leary challenge the naturalism-only assumption that the brain can fully generate consciousness. Instead, they suggest that human beings possess an immaterial dimension that grounds reason, moral agency, and personal identity. For readers concerned with the philosophical and theological foundations of human dignity, the work provides a treatment that is both stimulating and compelling.
A distinctive strength of the book is its reliance on clinical experience. The authors build a case on experience rather than theory alone. They introduce cases in which patients experience severe neurological injury or loss of portions of their brains due to tumors and other abnormalities. In many of these cases, the patients retain their personality, temperament, and memory. Egnor and O’Leary consider split-brain surgery, contending that the unified subjective self remains intact, even when the left and right hemispheres of the brain are separated, disrupting normal communication channels. Surgeons perform this separation of the hemispheres in cases of severe epileptic seizures, in which electrical signals on one side of the brain increase in strength as they are transmitted to the other. A back-and-forth cyclic increase in the signals results in seizures in severe cases. In some of these surgeries, the corpus callosum, the “massive bundle of millions of nerve fibers that connects the two hemispheres of the brain,” is completely severed (p. 13). The result often calms the seizures’ intensity and frequency, but it never severs the conscious unity of the individual.
The volume contains enough medical-grade diagrams to demonstrate the expertise of Dr. Egnor yet expresses medical complexity in terms that allow non-physician readers to grasp the significance of the argument. Such comprehensibility may result from the work of the co-author, accomplished science writer and journalist Denyse O’Leary. However the work progressed, the collaboration works well. The complexities described add credibility without leaving readers with little foundational medical knowledge in the dust.
Early chapters address the lack of predictable correlation between brain abnormalities and the functioning intellect of patients afflicted with the various conditions described above. The human experience of working through life is, indeed, sometimes profoundly influenced by physical or mental handicaps that stem from such abnormalities. But in many more cases than one might expect, the intellect remains unaffected or minimally impacted. And in every documented case, the consciousness of the individual is always a unified single entity. Egnor and O’Leary make the case that this lack of connection to the physical condition is due to the immaterial (or as they contend, the immortal) nature of the conscious essence of humanity.
The authors also consider episodes of near-death experience and unexpected lucidity in deep coma. These are phenomena that, while not conclusive in themselves, raise legitimate questions about the sufficiency of materialist accounts of mind.
The case made in this work does not overstate documented medical results but instead uses case studies that serve to reveal aspects of human consciousness for which neuroscientists have at best incomplete theories. For the authors, such cases invite humility about what brain science can explain and remind us that purely physical descriptions cannot adequately explain the complexity of human experience. A materialist approach is insufficient to account for the described phenomena.
Egnor has shared in lectures that he has studied the philosophy of Thomas Aquinas and holds a Thomistic interpretation of human nature. He and O’Leary cite classical thinkers’ work showing that human capacity for abstract reasoning cannot arise solely from matter. Humans’ intellectual ability to contemplate abstract ideas and comprehend immaterial realities suggests a spiritual dimension that transcends neurological causes.
While readers may differ on how best to describe this immaterial aspect, the book’s treatment underscores an important bioethical point: Human dignity is not reducible to functional capacity or neurobiological performance. Rather, the ontological reality of the person as an embodied yet transcendent being is grounded in deeper spiritual levels than materialism can provide.
The authors also address the unity of consciousness—our coherent, continuous, universal personal experience of consciousness. Alternate theories often resort to explanations that fail to fully account for the human experience of the world through their minds. Egnor and O’Leary contend that the most compelling account is that human consciousness arises from a unified personal spirit-mind-soul nature, not from a combination of physical components. They point out that these alternate theories are often simply proposed explanations lacking empirical grounding.
This insight carries significant implications. If the person is fundamentally unified and not merely an assembly of physical capacities, then human dignity remains intact even in conditions of severe cognitive impairment, dementia, or brain injury. In such situations, the metaphysical grounding of dignity becomes especially important for bioethical deliberation and compassionate care.
The authors’ reflections on free will further support their understanding of the physical and spiritual dimensions of human experience. Moral awareness and sensitivity cannot be explained by deterministic processes. Egnor argues instead that genuine choice is both philosophically defensible and consistent with the lived experience of patients and practitioners. Physiology and biochemistry have no causal ability related to human decision-making. Instead, evidence suggests that deliberation and intentional action involve a dimension not strictly confined to biomedical factors.
For Christians concerned with bioethics, this view resonates with long-standing theological affirmations of human responsibility, moral discernment, and the sanctity of the moral life.
The Immortal Mind does not claim to settle every debate, nor does it dismiss legitimate insights from neuroscience. Rather, the book’s contribution lies in calling attention to the limits of strictly materialistic accounts and inviting a richer, more thorough understanding of the human person. The writing style encourages humility related to the mystery of consciousness and openness to philosophical traditions that affirm the spiritual dimension of humanity.
For a field like bioethics—where decisions often hinge on how we define personhood, agency, and human worth—the work provides a timely reminder that scientific description, while indispensable, cannot by itself answer the deepest questions about what it means to be human.
The Immortal Mind will not persuade all readers, but it offers thoughtful analysis, a wealth of clinical insight, and a framework for reflection that aligns with a robust, dignity-affirming perspective regarding what it means to be human. As such, it merits careful attention from scholars, clinicians, theologians, and all who are committed to upholding the sanctity of human life in an age increasingly tempted to reduce the person to the measurable and the material.
Rick Townsend, “Review of The Immortal Mind,” Dignitas 32, no. 3–4 (2025): 31–32, www.cbhd.org/dignitas-articles/review-of-the-immortal-mind.