Peer Commentary

Doubt, Uncertainty, and the Complexity of End-of-Life Decision-Making: A Commentary on the Bedside Challenge of Thomistic Hylomorphism

Back to Dignitas Issue

This issue of Dignitas posed the foundational question: What does it mean to be human? For most, the human capacity for reason surfaces as the defining feature that distinguishes Homo sapiens from other animals. The locus of the human intellect has been attributed to an immaterial mind, a universal consciousness, or a rational soul of divine origin. For centuries, philosophers and theologians have debated the integration of the body with an immaterial mind or rational soul. Eberl’s essay focuses very closely on Thomistic hylomorphism and artfully employs the term “chimera” to emphasize the concept of a whole comprised of disparate parts.

Platonic dualism versus Thomistic hylomorphism represents a worthy intellectual, philosophical, and theological debate, but what practical insights do these philosophical constructs offer to the practicing physician and clinical ethicist at the bedside? The bedside of a critically ill patient seems an inappropriate locale to debate the merits of Platonic dualism versus the Thomistic embodied soul. Yet, when disease or trauma compromise cognitive and intellectual capacities, the challenge of end-of-life decision-making for another embodied soul touches many points reflected in Eberl’s thoughts on human beings as rational animals.

When disease encumbers the body and brain and interferes with the immaterial soul’s conveyance of rational thought, the process of surrogate decision-making safeguards patient autonomy. This “substituted judgement” decision-making standard “substitutes” for the patient’s intellect through recall and application of the patient's values, wishes, and healthcare goals. Commensurate with Eberl’s commentary, the substituted judgement process not only protects autonomy but provides an important expression of humanity’s shared nature, protection of human dignity, and an opportunity to accompany a fellow human being approaching the end of life.

This response to Eberl’s defense of a chimeric hylomorphism begins with a basic comparison of substance dualism and integrated hylomorphism, acknowledges the physical and metaphysical consequences of uncertainty, and asks how these philosophic models might improve processes through which healthcare professionals and clinical ethicists attend to critically ill and comatose patients. Simply put, could a deeper understanding of hylomorphism enhance the quality of decision-making at the end of life?

Dualism and Hylomorphism

Plato posited a metaphysical soul confined within a physical body.[1] This dualistic description clashes with the Aristotelian and Thomistic concepts of an integrated mind-body interface. Aristotle universally framed change as the product of a constant actualizing principle (form) acting upon a passive indeterminate substance (matter). The constructs of form and matter apply to all animate and inanimate bodies. For Aristotle, the human body and soul simply represented a special case of matter and form.[2] Saint Thomas Aquinas advanced the Aristotelian hylomorphic framework to describe a dynamically integrated and inseparable mind, body, and soul.[3] The body is forged specifically to receive the immaterial soul, which in turn activates the material body. Although composed of disparate parts, life is experienced as a unified entity or a chimera.[4]

The hylomorphic models also recognize the social nature of human beings. Eberl posits that community represents a necessary component of human personhood and provides a core support structure for human dignity. The social contract, fundamental rights, and an implied moral requirement to promote human flourishing derive from the concept of personhood and the divine nature reflected through the individual.[5]

Additionally, Aquinas contends that a dualistic account places limitations on, and fails to recognize, the material and metaphysical complexity of human beings.[6] However, the comatose patient in the intensive care unit blurs distinctions between Aristotle’s concept of form activating matter, Platonic dualism with its separate body and soul, and Aquinas’s hylomorphism.[7] A drift towards dualism occurs when trauma or disease prevent expression of the rational soul’s activating nature and immaterial features such as kindness, intelligence, relationship, and humor. The person’s familiar physical qualities remain present; however, the features that distinguish the individual remain unexpressed, separated or metaphysically disembodied. Ironically, when the rational soul separates from the body at death, these quite different philosophic constructs approach a common dualistic terminus.

The Corrosive Nature of Denial and Uncertainty on Decision-Making

The surrogate method of decision-making defends patient autonomy when capacity falters and pursues informed patient representation through a trusted family member or friend. Substituted judgement decision-making serves as a proxy for the patient’s intellect.[8] Ideally, this process filters proposed treatment options through personal knowledge of the patient’s values and healthcare goals to choose in the patient’s best interests.

Like any human process, inherent faults plague surrogate decision-making. Uncertainty and denial commonly conspire to derail this process and drive overly aggressive treatment. A dogmatic adherence to aggressive treatment based upon prognostic uncertainty often leads to non-beneficial or futile treatment. The risk of unwarranted patient suffering rises, and the discernment sought through the surrogate decision-making process is lost.

For the faithful, suffering represents a direct consequence of a fallen world. There is a dignity found in purposeful suffering, but dignity fades when futile or non-beneficial treatment perpetuates needless suffering. Overly aggressive care in the face of obvious futility extracts a cost. The physical costs of needless suffering borne by patients, the moral injury borne by their caregivers, and the financial costs borne by society—all are by-products of decisions tortured by uncertainty and denial.

When indecision chooses overly aggressive treatment, the accountability for patient suffering diffuses. No one person fully owns the treatment decisions. The surrogate avoids decision-related guilt, the treatment team avoids medico-legal risk by accommodating the surrogate’s directives, but the patient suffers as a result. In certainty’s absence, requests to “do everything” devolve into a dignity-degrading study of mammalian physiology until an irrecoverable complication ends the suffering.

Eberl described a natural law-based obligation to avoid causing pain through intentional or negligent means. One could posit that non-beneficial treatment meets the definition of morally negligent means when providers set aside good medical judgment in the name of respect for autonomy. Ideally, the principle of respect for autonomy should be tempered by the principle of non-maleficence.

Death and Taxes, Can One Ever Be Certain?

 Uncertainty so permeates medicine that it challenges Benjamin Franklin’s glib commentary on death and taxes. Clearly, technologic advances have blurred clinical lines to the point that strict legal definitions of death have become a moving target. The Uniform Determination of Death Act (UDDA) arose in response to uncertainty unleashed by technologic advances and the organ procurement industry’s need for strict legal safeguards. The dead donor rule (DDR) also evolved to protect vulnerable persons from becoming unwilling sources of transplantable organs and to protect organ procurement surgeons from homicide charges.[9] Strict compliance with the DDR and the UDDA limit the donor pool to patients who have suffered irreversible cessation of cardiac and respiratory functions or irreversible loss of all brain functions.[10] In a cardiac death, the loss of palpable pulses, cardiac electrical activity, and respiratory effort are easily observable phenomena. Even the untrained observer recognizes a cold, motionless, and cyanotic body as a corpse.

In stark contrast, a brain death determination imposes a greater challenge. Visual clues mislead. Despite devastating neurologic damage, the patient appears heavily sedated or unconscious. However, an in-depth evaluation reveals absence of protective reflexes such as blink, cough, or gag. The usual startle or withdrawal responses to light, sound, touch, and noxious stimuli are also absent. A temporary cessation of ventilator support reveals the absence of self-generated breaths.[11] The body is present, but the soul’s animating characteristics seem absent or inaccessible. For these reasons, the equivalency of brain death and cardiac death remains a controversial topic despite internationally recognized criteria.[12]

In Search of the Soul

Because the symptoms of death distill to a global unresponsiveness of the heart and brain, one might posit these sites as fitting repositories for the conscious mind, or rational soul. Many great figures in philosophy, theology, and medicine have contemplated the location of the mind or soul, yet the true seat remains an enigma.

Sir Thomas Browne, seventeenth-century physician and author of Religio Medici, grappled with this very concept:

there is no Organ or Instrument for the rational Soul; for in the brain, which we term the seat of Reason, there is not anything of moment more than I can discover in the crany of a beast: and this is a sensible and no inconsiderable argument of the inorganity of the soul. . . . Thus we are men, and we know not how: there is something in us that can be without us, and will be after us; though it is strange that it hath no history what it was before us, nor cannot tell how it entered in us.[13]

The Christian conceptualization of the soul extends well beyond “inorganity” to profess a divine origin. The breath of God activates inanimate material and embodies the spirit. “Then the LORD God formed a man from the dust of the ground and breathed into his nostrils the breath of life, and the man became a living being” (Gen 2:7, NIV). Simply put, the inanimate form (man) only became a living human being with instillation of the divine: “The Spirit of God has made me; the breath of the Almighty gives me life” (Job 33: 4), and “The Spirit gives life; the flesh counts for nothing. The words I have spoken to you they are full of the Spirit and life” (John 6:63). Additionally, multiple Bible passages correlate death with the absence of breath and a disembodied spirit: “As the body without the spirit is dead, so faith without deeds is dead” (Jas 2: 26); “Jesus called out with a loud voice, ‘Father, into your hands I commit my spirit.’ When He had said this, He breathed his last” (Luke 23:46); and in Ecclesiastes, “At death, everything returns to where it came from; the dust returns to the earth from which it was taken, and the Spirit shall return to God who gave it” (12:7).

How do these concepts instruct families and physicians at the bedside of a dying patient? Uncertainty is not generally a factor present in a circulatory death determination. Life signs spontaneously cease, but because either an organ harvest or removal of support structures from a body exhibiting physical attributes of life follows a brain death determination, this process is haunted by uncertainty and the fear of participating in another’s death. A reliable indicator of the soul’s departure could spare so much heartache and conflict.

So, if the Thomistic model supports an immaterial rational soul inseparable from the physical body until death, then how does one respectfully consider both the clinically brain-dead patient and, more importantly, the profoundly brain damaged, ventilator dependent, and persistently comatose patient? An entrapped soul or a genie in the bottle metaphor seems theologically unconscionable and more aligned with Platonic dualism conceptually. To rephrase, a construct where material aspects imprison the immaterial strongly clashes with the Aristotelian and Thomistic constructs where form (mind or soul) activates and exerts control over matter (material body). Yet, if the unique feature that defines human experience reduces to a mind or the rational soul exerting its will upon the environment, then human quintessence reduces to autonomy. Disease, trauma, accidents of birth, senility, and even the dependent years of infancy and childhood would provide circumstance to diminish individual value based upon variable expression of autonomy. This seemingly unsolvable situation places the sanctity of life, the meaning of life, definitions of death, and human dignity in intolerable tension.

The basis of Eberl’s essay is that the Thomistic construct of an integrated material body and immaterial soul best solves conceptual issues of embodiment, metaphysical individuation, and reunion of body and soul post resurrection. Yet, the construct allows for disturbing possibilities. Advanced technologies such as functional MRI may one day discreetly localize the volitional centers or processes crucial for mind to body activation and then postulate locus and activity estimates for the mind or rational soul. Additionally, physical or metabolic damage accrued to those structures might predictably render autonomy irretrievable. What would become of humanity if science solved the chimeric nature of a man/soul hybrid and reduced it to a measurable force, specific structure, bodily location, or biochemical process? Would a map of physical and metaphysical connections enhance life experience? Would humanity benefit from metrics that precisely predict the impact of trauma or disease on future cognition and expression of autonomy, or would humans employ these metrics to hierarchically assign personal worth?

The Essence of Being Human

Many postulate that human exceptionalism reduces to consciousness, self-awareness, and a capacity for rational thought. In fact, those very qualities allowed for this discussion of Platonic dualism and Thomistic hylomorphism. Yet what it means to be human also recognizes boundaries and restrictions of the material world. So, it seems ironic that human beings, physically encumbered by physical limits of perception and accrued knowledge base, contemplate the infinite and profess a deep understanding. Sir William Osler was prescient when he observed that “no human being is constituted to know the truth, the whole truth, and nothing but the truth; and even the best of men must be content with fragments, with partial glimpses, never the full fruition.”[14]

Osler recognized the insatiable curiosity of the human mind and its inability to fully apprehend the infinite. Because many foundational questions regarding the true nature of mind, body and soul remain unanswered, uncertainty will opportunistically breed within a knowledge gap. The perplexing interplay of the physical and metaphysical, the source of consciousness, the origins of free will, and the ultimate question of a soul’s immortality remain expansive mysteries and matters of faith.

Thomistic hylomorphism provides a conceptual framework to reduce the imponderability of the human species. The finite human intellect cannot fully grasp an infinite God nor humanity’s unique mission to reflect a fragment of His nature. The framework bridges multiple contradictions to posit a finite body infused with an eternal soul, and the value of the whole distributes across the disparate parts.

 Limited knowledge coupled with the capacity for reason amplifies human uncertainty in what lies beyond physical death. The faithful believe the mind/rational soul lives on, yet the bedside struggle for discernment reveals uncertainty’s corrosive nature. To escape from a broken physical body and fallen world to an uncorrupted body in eternity should provide physical and emotional relief. Yet for the surrogate decision-maker, doubts of one’s own eternal destiny only amplifies uncertainty when making end-of-life decisions for another.

The integral differences of hylomorphism versus dualism add little to the bedside battle with uncertainty; however, the constructs produce a better understanding of each person’s intrinsic value and enhance expectations that one’s essence lives past the finite body. Despite those reassurances, the bedside scene remains a harsh reality of hard decisions confounded by doubts and soothed by faith. For me, this battle depicts what it means to be human.


[1] Sarah Broadie, “Soul and Body in Plato and Descartes,” Proceedings of the Aristotelian Society 101, (2001): 295,

[2] “Hylomorphism,” New World Encyclopedia, accessed August 29, 2023,

[3] Frederick A. Olafson, “Early Conceptions of the Soul,” Britannica, June 4, 2019,

[4] “Chimera,”, accessed October 18, 2023,

[5] Gregory Alexander, “Ownership and Obligations: The Human Flourishing Theory of Property,” Cornell Law Faculty Publications 653 (2013): 6,

[6] Simon Thomas Hewitt, “Aquinas on the Immortality of the Soul: Some Reflections,” Heythrop Journal 64, no. 1 (2023): 30,

[7] Olafson, “Early Conceptions of the Soul.”

[8] Alexia M. Torke, G. Caleb Alexander, and John Lantos, “Substituted Judgement: The Limitations of Autonomy in Surrogate Decision Making,” Journal of General Internal Medicine 23, no. 9 (2008): 1514,

[9] Scott J. Schweikart,” Reexamining the Flawed Legal Basis of the ‘Dead Donor Rule’ as Foundation for Organ Donation Policy,” AMA Journal of Ethics 22, no. 12 (2020): E1019–24,

[10] “The Uniform Determination of Death Act: An Effective Solution to the Problem of Defining Death,” Washington and Lee Law Review 39, no. 4 (1982): 1516–17,

[11] David M. Greer et al., “Pediatric and Adult Brain Death/Death by Neurologic Criteria Consensus Guideline: Report of the AAN Guidelines Subcommittee, AAP, CNS, and SCCM,” Neurology 101, no. 24 (2023): 1112–32,

[12] Schweikart,” Reexamining the Flawed Legal Basis of the ‘Dead Donor Rule,’” 1022.

[13] Sir Thomas Browne, “Religio medici,” in Religio medici, A Letter to a Friend, Christian Morals, Urn-burial, and Other Papers (Boston: Ticknor and Fields, 1862), sec. IV, para. XXXVI,

[14] Sir William Osler, Aequanimitas: with Other Addresses to Medical Students, Nurses and Practitioners of Medicine-a History and Philosophy of the Profession (London: H.K. Lewis, 1914), 416.