Why the Thomistic Defense of "Brain Death" Is Not Thomistic: An Analysis from the Perspectives of Classical Philosophy and Contemporary Biophilosophy

THE ONGOING DEBATE on "brain death" (BD)—also known as the neurological standard for the determination of death—reached its half-century mark in 2018. In August 1968, the Ad Hoc Harvard Committee introduced "irreversible coma as a new criterion for death."¹ Despite intense controversy, and the lack of both a conceptual rationale and scientific validation, the Harvard BD criterion gained widespread medical and legal acceptance, especially the endorsement by the 1981 President's Commission for the Study of Ethical Problems in Medicine and Biomedical and Behavioral Research.² The Commission also gave BD its first conceptual justification, which was essentially the thesis of James Bernat and his colleagues,³ according to which: (1) the brain is the central somatic integrator "necessary for the functioning of the organism as a whole," and (2) consequently, a brain-dead (BD) patient on life support is merely a collection of artificially maintained, unintegrated organs and subsystems.⁴ Bernat's emphasis on the centrality of the brain, especially with respect to the vegetative functions of a human person, is explicitly stated in the following passage:

It is primarily the brain that is responsible for the function of the organism as a whole: the integration of organ and tissue subsystems by neural and neuroendocrine control of temperature, fluids and electrolytes, nutrition, breathing, circulation, appropriate responses to danger, among others.⁵

The intervention of the President's Commission did not suppress the BD controversy, however. Instead, the controversy has expanded to involve the Catholic Church and cause divisions among Catholics, especially following John Paul II's 2000 Address to the 18th International Congress of the Transplantation Society.⁶ Since the mid-1980s, medical evidence has repeatedly falsified the above thesis of Bernat and the President's Commission.⁷ As a result, in 2008, the President's Council on Bioethics formally rejected "the false assumption [of] the brain [as] the 'integrator' of vital functions."⁸ Nevertheless, the council sought to rescue BD with another conceptual justification—the "fundamental vital work" rationale,⁹ according to which a living human organism is defined by its "self-preserving commerce with the world,"¹⁰ that is, by the presence of spontaneous breathing and/or consciousness.¹¹

Because of its overt deficiencies, the "fundamental vital work" rationale has not elicited much interest among BD supporters.¹² Moreover, from the Catholic perspective, to accept the council's rationale would also amount to saying that embryos and fetuses in utero are not living human beings since they lack both spontaneous breathing and consciousness.¹³ For this reason, pro-life, pro-BD Catholic scholars have endeavored to develop new arguments to justify the BD paradigm. The most recent rationales—the only two currently in use within the Catholic tradition in defense of BD—are (1) Patrick Lee and Germain Grisez's "substantial change" rationale, according to which BD patients are no longer humans (and therefore dead) because they have lost the radical capacity for sentience even though they remain somatically integrated;¹⁴ and (2) the rationale advocated by Melissa Moschella and Maureen Condic, according to which BD patients are dead because they have lost the root capacity for self-integration, as evidenced by the loss of the capacity for spontaneous breathing and the loss of the capacity for sentience.¹⁵

The point of this article is to determine whether these rationales cohere with the Catholic Church's understanding of human nature based on Aristotelian-Thomistic hylomorphism. My argument is that they do not, and that they also contradict the contemporary holistic biophilosophical understanding about life and organisms.

I. Critical analysis of Lee and Grisez's rationale

In a way similar to the 2008 President's Council, Patrick Lee and Germain Grisez also acknowledge that the medical evidence presented by Shewmon has disproved the thesis of the brain as central somatic integrator, and that BD patients are living beings with somatic integration. Nevertheless, Lee and Grisez argue that the BD standard remains valid because "what is alive after total brain...