Are Brain Dead Individuals Dead? Grounds for Reasonable Doubt

Abstract

According to the biological definition of death, a human body that has not lost the capacity to holistically organize itself is the body of a living human individual. Reasonable doubt against the conclusion that it has lost the capacity exists when the body appears to express it and no evidence to the contrary is sufficient to rule out reasonable doubt against the conclusion that the apparent expression is a true expression (i.e., when the conclusion that what appears to be holistic organization is in fact holistic organization remains a reasonable explanatory hypothesis in light of the best evidence to the contrary). This essay argues that the evidence and arguments against the conclusion that the signs of complex bodily integration exhibited in ventilated brain dead bodies are true expressions of somatic integration are unpersuasive; that is, they are not adequate to exclude reasonable doubt against the conclusion that BD bodies are dead. Since we should not treat as corpses what for all we know might be living human beings, it follows that we have an obligation to treat BD individuals as if they were living human beings.

I. ASSUMPTIONS AND WORKING CONCEPTS

The Factual Question and the Ethical Question

The factual question behind this essay is whether an individual who suffers total brain death is dead. ¹ The factual question bears on the ethical question of how to relate properly to brain dead (BD) individuals. As with all ethical questions, this can only be answered in light of sound knowledge regarding what human goods are at stake in the question under consideration. Are we or aren’t we dealing with the good of human life? Most would agree that if BD individuals were alive, they should not be treated as corpses. The factual distinction alone (between being alive and dead) does not settle the question of what kind of treatment would be due to such a disabled human being. This essay does not consider that question in any detail. ²

Working Definition of Death

The essay presumes and does not argue for what has been called the biological or organismic definition of death (Bernat, Culver, and Gert, 1981; Shewmon, 2001). According to this definition, death is the irreversible cessation of functioning of an organism as a whole. So humans die when the biological organism that materially constitutes them dies. The organism dies when it irreversibly ceases to function as an organism (John Paul II, 2000, no. 4). ³ Although we are concerned here with human death, the biological definition applies to all organisms, including the simplest one-celled organisms. At the same time, it only applies to organisms. The demise of parts of organisms, such as cells, tissues, organs, and even organ systems, can only be referred to as “death” analogically, inasmuch as they cease to carry out dynamic functions, including functions necessary to sustain life. Likewise, the kinds of “death” involved in “spiritual death,” “death of nations,” “death of chivalry,” etc., are analogical inasmuch as each involves some sort of definitive cessation.

Moreover, according to the biological definition, death is a momentary event, not a process. Since death is the irreversible cessation of organismal type function, and a body is either or not an organism, it follows that a body is either or not dead. Following Leon Kass, although dying might be a continuous process, it does not follow “that death, in contrast with dying, is a continuous event” (Belkin, 2014, 84). A living organism may be disabled, may become incapable of many expressions of organismic functioning, but it is not dead until it definitively ceases to be as an organized whole.

Finally, the biological definition holds that somatic integrative unity is not a part of an organism as cells, tissues, and organs are parts of an organism, but rather the intrinsic arrangement of and relations between parts, where each part exists for the sake of the whole, is only fully intelligible in terms of its relation to the whole. This arrangement of and relationship between parts—that is, this integration—is an intrinsic property of the organism and not imposed on the body by anything outside it (although a living body may need external assistance to maintain its integration). The contrary of somatic wholeness is not brokenness, or sickness, or unwholesomeness, or anything per se empirically observable, but rather the absence of integration. So, although events are ordinarily among the paradigm cases for things that are observable, the event of death—that is, the moment of the irreversible cessation of this arrangement of and relationship between a body’s parts—cannot be observed. We can only observe its signs, such as the cessation of breathing, cardiac activity, brain activity, rigor mortis, and cellular necrosis.

“Reasonable Doubt”

This gives rise to a problem. If death per se is not observable, and we must rely on somatic signs to determine whether or not it has occurred, how can we be certain that a body is dead when it expresses activity identical or similar to a living body? How can we know that we are observing a mere assemblage of parts which because of complex but localized interactions gives the appearance of a unitary whole and not a truly unitary whole? This is the problem we confront when faced with a ventilated BD body.

Moreover, what measure of doubt must we have regarding whether BD individuals are dead to give rise to moral obligations? Certitude is a state of mind correlative to our assent to propositions. It is achieved when a proposition is judged to be certain, proved, or established. ⁴ Most philosophers agree that certitude is possible in relation not only to self-evident propositions (such as the principle of non-contradiction) and logically certain statements (such as “2 + 2 = 4”) but also to empirical (or a posteriori) propositions (Rollins, 1967, 67). When evidence sufficiently dispels doubt about the verity of an empirical proposition, we have empirical certitude.

Certitude can be contrasted with other states of mind, for example, the state of doubt, and the state of holding something as an opinion. We are doubtful when we believe that the truth of some proposition is uncertain, unsure, or unproven. But certitude is not merely the absence of doubt. It is rather an assent that excludes doubt. A stranger may tell us his name, for example, and if we have no reason to doubt what he says, we may give his statement undoubting assent. But this is not yet certitude, since we do not have strong reasons excluding doubt, and are ready to withdraw our assent in the face of persuasive reasons to do so. Nor is holding a proposition as probable certitude, but rather an opinion.

The empirical proposition concerning us here is that a “brain dead” body is a corpse (i.e., not a living human body). ⁵ Certitude as to its verity is established by excluding doubts to the contrary. Doubts are dispelled and certitude established by persuasive evidence. Evidence includes all facts and information, including philosophical argument, that furnish proof of the proposition’s verity. Reasonable doubt against the proposition arises when insufficient evidence is adduced in favor of the proposition, including when counterevidence seems to support its contrary. Reasonable doubt refers to a state of mind that reasonable people could come to after considering the best available evidence for and against the proposition.

“Moral Certitude”

I would like to introduce the term “moral certitude.” The term ordinarily is used to refer to one’s assent arising from judgments based on ordinary and predictable expressions of human character, for example, the verity of a mother’s love or the reliability of historical testimony. I am using the term differently here. Moral certitude refers to the assent that stands as a necessary condition for proceeding in good faith with actions made on the basis of that certitude (New Catholic Encyclopedia 2013, 235). As the term suggests, moral certitude is a product of both speculative and practical reasoning. As speculative, it entails a judgment excluding reasonable doubts that some proposition is true. As practical, it sanctions action. For if adopting some alternative requires that some factual state of affairs be the case before proceeding would be licit, then one should exclude reasonable doubts as to whether it is the case before proceeding. For example, a hunter should have moral certitude both that the object in his crosshairs is the lawful game he is hunting and that there is an adequate backdrop to stop his bullet in the case of a missed shot before he shoots. If, say, because of inclement weather his vision is impaired and he is unable to exclude reasonable doubt as to whether the object stirring in the distance is another hunter, then he is morally obliged to refrain from shooting until that doubt is expelled.

Applied to the BD scenario, transplant doctors and those who advise them should have moral certitude that a BD body is a corpse before removing its organs. If despite the best evidence available reasonable doubt persists as to whether this is the case, then they should refrain from the business of organ harvesting. This presumes the moral principle that living human beings should not be treated as corpses.

In proposing the term “moral certitude,” I do not mean to introduce a substantive distinction between it and empirical certitude. Inasmuch as both types imply that doubts against some empirical proposition are dispelled, the terms are coextensive. The bar of empirical certitude is, as it were, the same height as the bar of moral certitude. In clearing the one, we clear the other. The distinction in terms is meant to indicate a difference in effects. Moral certitude not only denotes the absence of doubts against the truth of a proposition but also acts as a sanction for action.

This account of moral certitude needs to avoid establishing an impossibly high bar for resolving the question at hand. Moral certitude does not exclude all doubts, logical and metaphysical. It excludes, as I said, reasonable doubts. The doubts (or, for that matter, certitude) of one who is ignorant of the complexities of the question, unfamiliar with the literature, or biased toward a particular conclusion cannot be held to be reasonable. But when the best available evidence generates persistent doubts about some conclusion, even a widely accepted conclusion; and when the best attempts to dispel those doubts can do no more than to throw the doubts into doubt, but not dispel them; and when the doubts are held by well-informed participants in the BD debate, who have taken due measures to exclude in themselves bias, then their doubts are reasonable. The bar is high, but not impossibly high.

It is true that the use of all empirical evidence in medicine is no more than probabilistic. Absolute certitude, whatever it is, is not the measure for the sanctioning of new drugs or surgical procedures, or for institutional review boards sanctioning experimentation on human subjects. Yet before a drug is distributed for public consumption or subjects used in research protocols, those who authorize the procedures are required to rule out reasonable doubt that the procedures will kill or gravely harm anyone. I say kill or gravely harm, because I do not think moral certitude is required when the risks posed by some procedure are minor. But bringing about the death of a human being is never a minor matter. Therefore, just as researchers and executives at big pharmaceuticals are rightly required to demonstrate beyond a reasonable doubt that their drugs are safe for consumers, so too those who defend, authorize, and perform transplants from BD bodies should be morally certain the subjects are not living human beings.

Finally, lacking moral certitude that BD individuals are living human beings is different from lacking moral certitude that they are dead. This essay concerns whether there is reasonable doubt that they are dead. Since the aim of practical reasoning is to arrive at moral knowledge capable of directing human action in ways that are consistent with what is true and good, and since the good of human life is most immediately at stake in this question, a reasonable doubt suffices to justify a prohibition from all interventions that would be unethical to perform on living human beings.

II. POSING THE QUESTION

The President’s Council on Bioethics: November 9, 2007 Meeting

A significant moment in my own thinking occurred at the 2007 Fall meeting of The President’s Council on Bioethics (PCBE) in Washington, DC, at which I was a spectator. Dr. Alan Shewmon, Professor of Pediatric Neurology at UCLA Medical School, was invited to comment on the Council’s draft of a White Paper entitled “Controversies in the Determination of Death” (Shewmon, 2007a). In that paper, the Council reaffirmed both the neurological criteria for death as proposed in 1968 by a Committee of the Harvard Medical School, as well as the theoretical justification for the criteria that was set forth 13 years later by an advisory commission of the US president in a report entitled “Defining Death” (Ad Hoc Committee of the Harvard Medical School, 1968, 85–88; President’s Commission for the Study of Ethical Problems in Medicine and Biomedical and Behavioral Research, 1981). The justification rested on the following line of reasoning: the irreversible loss of the integrated functioning of the organism as a whole constitutes death; the brain is the master regulator of the body’s integrated functioning; one whose brain is irreversibly nonfunctioning cannot perform integrated functioning; therefore, the irreversible cessation of all brain activity constitutes death.

Shewmon presented evidence for many expressions of apparently integrative functioning in ventilated BD bodies (Shewmon, 2007a). The impressive list, which he first published in 2001 in this journal, is worth repeating here (Shewmon, 2001, 470–2):

• •respiration (BD bodies are apneic, so air must be mechanically supplied to the lungs);
• •nutrition;
• •homeostasis;
• •elimination, detoxification, and recycling of cellular wastes throughout the body;
• •energy balance, involving interactions among liver, endocrine systems, muscle, and fat;
• •maintenance of body temperature and fluid and electrolyte balance;
• •wound healing;
• •fighting of infections and foreign bodies through interactions among the immune system, lymphatics, bone marrow, and microvasculature;
• •development of febrile response to infection;
• •cardiovascular and hormonal stress responses to unanesthetized incisions;
• •successful gestation of a fetus in a BD woman;
• •sexual maturation of a BD child;
• •proportional growth of a BD child;
• •resuscitability and stabilizability following cardiac arrest;
• •ability to recover from episodes of hypotension, aspiration, and sepsis;
• •overall ability to maintain physiological stability with little medical intervention (although with much basic nursing care) in a nursing facility or even at home, after discharge from an intensive care unit.

His evidence was so persuasive that the PCBE abandoned the old rationale and went back to the drawing board to formulate a new one. ⁶

Most people are familiar with the fact that the criteria proposed by the 1968 Harvard Committee were enormously influential in shaping national and international consensus and law on the definition of death, indeed for practically altering how the whole world views death. Fewer know, however, the troubling fact that the Committee merely asserted without defense that brain death was human death. ⁷ The opening sentence of the Committee statement reads: “Our primary purpose is to define irreversible coma as a new criterion for death” (emphasis added). Define it as such they did. But the Committee made no effort in the statement to answer—indeed expressed no interest whatsoever in—the question of why neurological death (referred to confusingly as “irreversible coma”) is human death. ⁸ Commentary in the weeks after the statement’s publication made clear that at least one member of the Committee, its chairman Dr. Henry Beecher, did not intend the definition to provide conceptual clarity on the metaphysical reality of death. Since he did not believe death could be pinpointed, he was more interested in supplying a definition that provided determinate boundaries for doctors and families dealing with the messy and contingent facts of the dying process (Belkin, 2014, 84). ⁹ He admitted that the neurological criterion was arbitrary. What he wanted was to define a physiological condition that was irreversible (“the state of no return”; Belkin, 2014, 84), could be clearly determined, and that was useful for minimizing the waste of transplantable organs (Beecher and Dorr, 1971, 120–2). ¹⁰

When it came to the question of why a new definition was needed (not why the definition was adequate), the reasons set forth in the Harvard Committee’s statement were purely utilitarian: to relieve the burden on families and hospitals caring for BD individuals, to open beds occupied by BD patients, and to obtain an increased supply of organs. ¹¹

A decade would pass before the “brain-as-regulator-of-holistic-integration” rationale was introduced. ¹² The rationale was quasi-canonized by the President’s Commission in 1981 and then energetically championed over the next 10 years by Bernat, Culver, and Gert (1981; 1982; 1984; Bernat, 1984; 1989; 1992; 1998; Gert, 1995; Capron et al., 1982). In the 1990s, Shewmon (1992; 1997; 1998a; 1998b) published credible evidence throwing the rationale into doubt.

Today that doubt has become an international consensus. Scholars from all over the philosophical spectrum—defenders and critics of the dead donor rule, proponents of “higher” brain death, of the biological definition, and of the Christian definition—are united in thinking that the rationale of the 1981 President’s Commission is unsound. For example, the editor of a 2001 issue of the Journal of Medicine and Philosophy dedicated to BD, after reading Shewmon’s evidence, writes: “Equating brain death with loss of somatic integrative function, while useful for clinical, transplant, and policy purposes, is physiologically inaccurate and theoretically incoherent” (Lustig, 2001, 448). Likewise, John Lizza, defender of the cortical criterion for death, in response to Shewmon’s research, writes: “At bottom, individuals who have lost all brain function but continue to function in such biologically integrated ways for such lengthy time frames are integrated organisms of some sort and cannot be classified as corpses or dead organisms” (Lizza, 2004, 52). Truog, Miller, and Halpern recently stated in a piece in the New England Journal of Medicine: “Patients meeting criteria for brain death were originally considered to be dead because they had lost ‘the integrated functioning of the organism as a ‘whole’. … Over the past several decades, however, it has become clear that patients diagnosed as BD have not lost this homeostatic balance but can maintain extensive integrated functioning for years” (Truog, Miller, and Halpern, 2013, 1288). The list of critics of the 1981 rationale includes: Halevy and Brody (1993), Brody (1999), Youngner and Arnold (2001), Seifert (1993; 2000), Byrne et al. (2000), Taylor (1997), Veatch (1982; 1992; 2005), Gervais (1986), Wickler (1995), and Grisez and Lee (2012), to name just a few.

Three Interpretations of the Evidence

Shewmon offers conclusive evidence that the bodies of reliably diagnosed BD individuals can continue to exhibit a relatively high degree of apparent organized, holistic activity. That evidence has been given three interpretations by defenders of the biological definition of death: first, that the activity is human organismic activity and therefore the BD body is the body of a living human individual, albeit of one who is terribly disabled; this is Shewmon’s own position, as well as that of Nicanor Austriaco (Austriaco, 2009; 2011, 195–202); second, that it is not human organismic activity, but merely a semblance of it, and therefore the BD body is, strictly speaking, a corpse; this is the position of Maureen Condic and Nicolas Tonti-Filipini (2011; 2012); third, that it is organismic activity, but not human organismic activity; when the brain dies, a substantial change takes place such that what was once the body of a living human individual is now a subhuman body; this is the position of Germain Grisez and Patrick Lee (2012).

The Reasonable Doubt Argument

To gain certitude that a BD body is a corpse, doubts against the proposition need to be dispelled. To formulate the chief doubt that needs dispelling, a summary of the argument thus far will be helpful. Humans die when their bodies die. Human bodies die when they irreversibly lose the capacity (or cease) to holistically organize themselves. Any human body (BD or otherwise) that has not lost this capacity is the body of a living human individual. As an event, the precise moment at which the body ceases to self-organize cannot be observed. But the results of the event can be observed. We can establish that a body has lost the capacity to self-organize through observing it under controlled conditions.

Reasonable doubt against the conclusion that a body has lost the capacity exists when the body appears to express it and no evidence to the contrary is sufficient to rule out the conclusion that the apparent expression is a true expression. Another way to formulate this is to say that reasonable doubt exists when the conclusion that what appears to be holistic organization is in fact holistic organization remains a reasonable explanatory hypothesis in light of the best evidence to the contrary (Brugger, 2012a, 264).

III. REPLYING TO ARGUMENTS

I mentioned above that of the three interpretations of Shewmon’s research by defenders of the biological definition of death, two argue that BD individuals are dead. Both arguments deserve careful consideration.

Argument 1: Expressions of organization in BD bodies are merely semblances of true somatic organization

The first is a modified version of the argument proposed by the 1981 President’s Commission. It holds that the irreversible cessation of integration at the level of the whole organism constitutes death; that the brain is necessary for true organismal integration; therefore, total brain destruction constitutes death. The view takes seriously the apparent signs of integration in BD bodies, but argues that none of the many expressions can be attributed to the organism as a whole. Each is no more than an expression of localized interactions between cells. Because of the death of the brain, the body is in fact no longer an integrated living whole, but the manifest signs of disintegration are masked by medical technology (Bernat, 1984, 48; Tonti-Filippini, 2011, 310).

Before engaging the argument, it should be said that the general outlines of Shewmon’s list of apparent expressions of integration in BD bodies are not in dispute. ¹³ What is disputed is how they should be interpreted. Maureen Condic’s formulation of the argument seems to me most rigorous (Condic, 2016). ¹⁴ She begins by noting that cellular life may persist in bodies for days after death has occurred. When technological interventions are used, this time period may be much longer. Those interventions enable cells and organs to interact at a local level in complex ways, some of which can appear to be the activities of human bodies. We therefore need a way of distinguishing between expressions of activity founded simply on the biological properties of individual cells and the connections between them formed during organismic life and activities expressive of human life: “What signs can we rely on to indicate with sufficient certainty that a human being has died?” (Condic, 2016, 259) Elaborating this, Condic writes:

[D]etermination of death requires us to discern when a body has completely lost its capacity for global and autonomous self-regulation and integration, versus when a living human being is merely “blocked” from exercising its self-integrating capabilities, as when a head injury causes swelling which temporarily blocks the body’s ability to regulate its own breathing. (Condic, 2016, 263)

Addressing her own questions, she proposes the classical definition of human beings as “rational animals.” She says the definition is useful because it affirms two “essential” qualities of human nature: humans are biological organisms of the kingdom animalia and they are capable of reason (Condic, 2016, 264). Systematizing the insight, she proposes “two clear criteria for human life”: (1) “[P]ersistence of mental function,” and (2) “[P]ersistence of global, autonomous integration of vital function,” what she refers to as “animality” or “organismal function” (Condic, 2016, 264).

She says if we apply these criteria to specific cases, we can distinguish between living human beings and dead bodies. For example, an individual in a persistent vegetative state exhibits “sustained, autonomous integration of bodily functions.” This individual is clearly a living human organism, even if incapable of mental activity. Likewise, one who suffers complete spinal cord transection exhibits little or no autonomous bodily integration, and yet may be conscious. This is an infallible sign that the person is alive.

But when she applies the criteria to BD individuals, she finds no evidence of the persistence of living human beings. Because the brain is necessary to mental function, and BD individuals have lost all brain function, they do not and cannot exhibit any mental activity. Likewise, BD individuals do not and cannot exhibit persistence of somatic integration. Why? Because the brain is necessary for integrative function: “following the irreversible cessation of all brain function including the brain stem … autonomous integration cannot be maintained (i.e., the body is no longer able to function as an organism...)” (Condic, 2016, 265). She does not deny that complex cellular functions continue that may mimic the functions of a living human body. But she thinks that if the whole brain is dead, a body is nothing more than an aggregate of nonintegrated human cells carrying out behaviors that they (as it were) learned before the individual died: behaviors organized to a whole that no longer exists. ¹⁵

The obvious question is how do we know that these activities are not expressions of holistic organization if they appear very similar? The answer is critical to the success of her argument. She says we know because each and every function that takes place in BD bodies is also observed in cells and tissues ex vivo. Homeostasis, energy balance, wound healing, stress response, elimination/detoxification, immune defense, proportional growth, temperature regulation, and limited sexual maturation—all these functions are either observed in isolated cells and tissues supported ex vivo or could easily be reproduced ex vivo. Therefore, none of the functions expressed singly nor all of them together can be used as a reliable measure for determining whether or not a human being is alive: there is no evidence for biologic integration above that seen in human cells.

To say there is no observable evidence for X does entail the conclusion non-X. The evidence may be elusive. Or the immediately exercisable capacity to exhibit functions that provide evidence for X may be blocked by pathology. Moreover, to argue that because X and Y are similar, and Y is not Z, therefore X is not Z is fallacious. It would only be sound if X and Y were identical. The fact that all the functions observed in BD individuals are also observed in isolated cells and tissue ex vivo, and that isolated cells and tissue are not living human beings, does not entail the conclusion that BD individuals are not living human beings. For that to be true, the premise would also have to be true that BD individuals are identical to isolated cells and tissues ex vivo, which is not obviously true. A BD body may be a human organism whose capacities for higher-level operations are blocked by severe pathology. BD individuals were once alive. Their bodies autonomously carried out vegetative functions that were undeniably an expression of this life. The same vegetative functions are observed after brain death, although the body in which they are observed may not possess the physiological stability it did before. There is uninterrupted continuity of expression in those functions before and after brain death. A healthy human organism autonomously carries out functions at the vegetative, sensory, and rational levels. We know that functioning at all three levels can be impaired, and functions even lost, without loss of the organism. If a body continues autonomously to express functioning at any of the three levels, including at the vegetative, we presume the organism persists. From all appearances, BD bodies continue to express vegetative function. The prima facie conclusion, therefore, is that the organism persists after brain death. But since we have certitude that all higher-level expressions of life (sensory consciousness and rationality) are lost, and (for the sake of argument) we conclude that all remaining somatic functions can be explained in terms of the functions of parts, certitude that the organism persists seems to be excluded. In other words, Condic’s argument is sufficient to exclude moral certitude that BD individuals are alive. But her argument does not yield certitude that they are dead. It does not rule out reasonable doubt that what remains is a very sick person.

Coordination versus Integration

Condic uses an elegant heuristic to distinguish between the order that takes place in parts and the order exhibited by wholes; she refers to the one as “coordination” and the other as “integration.” Coordination is an organized physiologic response mediated by localized intercommunications between cells (i.e., the interactions of parts) for the sake of benefits restricted to the functions of parts. Chemical signals, for example, can elicit inherently restricted functions, even—given blood circulation—throughout the whole body. But because they are stimulated by localized signals, they do no more than elicit harmonious or common action between and among parts. Integration, on the other hand, is a global response elicited by multiple sources of information drawn from the overall state of the body. It combines the information to respond in context to diverse bodily conditions for the sake of the well-being of the whole.

Like the 1981 President’s Commission, Condic holds that the brain is the master regulator of bodily integration. Without its activity, the body is incapable of mounting globally unified “context dependent” responses to information communicated from multiple sources in the body for the sake of the whole. In other words, without the brain, all somatic activity is coordination: no modification, enhancement, or suppression of function in response to information derived from the whole body. Though coordinated processes persisting after brain death can be very complex, they are not functions of an integrated whole.

Outstanding Questions for Condic’s Heuristic

The coordination-integration distinction enables us to conceptualize and name expressions of complex, ordered organization in cells and tissues, and to distinguish them conceptually from organization existing in organisms, even when the expressions appear similar. But we need more than a conceptual schema. Condic says that BD bodies exhibit no integrative functioning beyond the cellular level. But they appear in some cases to express true vegetative function. What signs can we identify to distinguish between coordinated and integrated systems? For example, according to Condic’s classification scheme, the body of a persistently comatose, terminally ill patient, who is suffering from multi-organ failure and dependent on a ventilator, constitutes an integrated system, whereas the body of a cardiovascularly stable BD individual whose non-brain systems are functioning normally is merely a corpse expressing localized coordinated processes. What evidentiary basis do we have for concluding that the one body expresses true integration and the other merely coordination? Without such criteria, how is the heuristic useful for more than formal classification? For example, apart from consciousness, how is an end-stage ALS patient, who cannot move a muscle and cannot breathe, any more integrated than a chronic BD individual? Or again, why are patients who lose neurologically based somatic integration, including cranial nerve reflexes (e.g., rare cases of the autoimmune disease Guillain–Barré syndrome) integrated?

Argument 2: BD bodies may be organisms, but they are not human organisms

Lee and Grisez begin, too, with the definition of a human being as a rational animal: “anything that entirely lacks the capacity for rational functioning is not a human being” (Lee and Grisez, 2012, 277). By “entirely” they mean it lacks both the present capacity to exercise rational functioning, as well as the capacity to develop that capacity. Since rational functioning in an animal depends on the activity of the senses, to possess either the capacity for rational functioning or the potentiality for it, an individual must possess the capacity, or the potentiality for sentient functioning. And so “anything that entirely lacks the capacity for sentient functioning also lacks the capacity for rational functioning and so is not a human being” (Lee and Grisez, 2012, 277). In mammals, a brain is necessary to exercise the capacity for sentient functioning. “Therefore, any entity that entirely lacks a brain and the capacity to develop a brain is not a human being” (Lee and Grisez, 2012, 278). Individuals who suffer total brain destruction possess neither a functional brain nor the capacity to develop a brain. Therefore, they are not animals and so a fortiori are not rational animals.

This has been called the “radical capacity for sentience” argument (RCS, Austriaco, 2009). Lee, and Grisez do not deny that BD bodies sometimes are—in a qualified sense—living, human, and organized. But what lives after total brain death is not the individual whose brain died or even any member of the human species (Lee and Grisez, 2012, 277). “A substantial change has occurred: the human being has passed away, and although the remains include a large living entity, that entity is not a human organism, and so is not the individual who suffered total brain death” (Lee and Grisez, 2012, 279). It is more like a sustained “waste-down unit” (a torso), “human in the sense that all of its cells would have the human genome, and they would constitute tissues and interact as human cells do,” but not a whole human organism (Lee and Grisez, 2012, 277).

Grisez and Lee acknowledge that it is “rationality” and not sentience that “differentiates human beings from other animals” (Lee and Grisez, 2012, 278). The RCS argument focuses on sentience because it presumes the axiom of scholastic philosophy that the cognitive starting point for all ideas is sensible images. ¹⁶ It follows that if the power of forming sensible images is irretrievably lost, then the power of rationality is also lost. ¹⁷ One who suffers total brain death loses the power and possibility of forming sensible images and so of rationality. The individual is no longer characterized by those operations, and so is no longer either rational or animal. Although integrated living operations may persist in a BD body, the individual who suffered brain death is dead.

Grisez and Lee concede that in principle a conscious individual who has irretrievably lost the capacity to act rationally (“to respond personally”) would no longer be a human being. But they argue that since the loss of this capacity in a conscious individual “cannot be proved,” the possibility is “merely theoretical” and therefore their account “does not warrant treating demented individuals as nonpersons” (Lee and Grisez, 2012, 283).

On what basis do they say it is impossible to prove that a conscious person has irretrievably lost the power of rationality? They do not reply. They say only that “as long as people are conscious, one cannot be sure that they will never again respond personally.” And again, “as long as people who seem to have lost their specifically human capacities are conscious … the completeness of their loss is neither obvious nor demonstrable” (Lee and Grisez, 2012, 283).

But it is not obvious that with the advance of neuroimaging techniques, we will never be able to demonstrate that the regions of a conscious person’s brain requisite for rational thought have been irreversibly damaged. And if one day this becomes a practical possibility, and we are presented with a conscious individual who has demonstrably lost the capacity for rationality, certainly there will be grounds for reasonable doubt that they are not living human beings.

Further, it is not certain that there cannot be an individual who is rational, but has lost the capacity for sensation. Say, for example, an evil neurosurgeon lesioned all inputs to someone’s central nervous system from all sensory modalities, removed all primary sensory cortices of the brain, and lesioned the secondary sensory association cortices. The individual would have lost the capacity for sentience, including the so-called internal senses of memory and imagination, as well as the capacity to develop those capacities. Has this individual lost the “radical capacity for sentience”? Should we consider the individual a living human being? If the answer is yes, then either the radical capacity for sentience is not dependent on the brain, or the status of a living human individual is not contingent on the radical capacity for sentience. ¹⁸

These two scenarios raise the problem of the a priori posture of the RCS argument: if the capacity is lost, one is dead, no matter what empirical evidence may be adduced to the contrary. Since the argument provides no compelling reason for concluding that conscious individuals who are irrecoverably nonrational or nonsentient cannot actually exist, the RCS argument is unpersuasive.

IV. FURTHER THOUGHT EXPERIMENT

Headless Body

Lee and Grisez propose a thought experiment about decapitation in support of their argument. The head of a living individual (John) is surgically separated from the rest of the body. Surgeons are able to avert fatal bleeding; oxygenated blood is provided to the head through a heart-lung machine; and the body is sustained on a ventilator. Both the head and the body continue to exhibit appropriate operations. The authors ask whether “the head and headless body, though physically separated, might remain parts of one human organism” (Lee and Grisez, 2012, 277). They reject this possibility, saying “once the two are separated, they can no longer affect one another, cannot interact” (Lee and Grisez, 2012, 277). Lack of interaction, however, may not be a decisive reason. Shewmon has persuasively argued that the somatic pathophysiology of patients with therapeutically compensated diabetes insipidus who suffer complete upper cervical cord transection (spinal cord injury: SCI) and are pharmacologically vagotomized (severing of the vagus nerve) “can be shown to be absolutely identical to that of a BD body” (Shewmon, 2001, 462; cf. Shewmon, 1999; 2004). If this is the case, then Lee and Grisez’s logic leads to the conclusion that the section of body below the spinal cord injury is not part of the patient; that both head and body are not strictly speaking parts of the same whole. Condic argues they are living human beings, but not human organisms (Condic, 2016, figure 2): they are alive, but the brain no longer integrates the rest of the body. She says just as pathology can block a human being’s capacity to exercise reason, so too it can block its capacity to function as an organism; in both cases, the human being can continue to exist.

Despite the plausibility of Condic’s proposal, it still seems inadequate. Integration is not simply a survival-enhancing capacity that can be blocked. It is, to use Shewmon’s terminology, a life-constituting capacity (Shewmon, 2001, 471). Without integration, there is no organismic life. The argument risks falling into anthropological dualism: mental function exists, so the entity is a living human being; but organismic function does not, so the human being is not a body. ¹⁹ Condic might reply: the head is still integrated and the head is part of the body, therefore a living integrated body still exists. If this is the case, then the headless segment is strictly speaking dead. Why then does it continue to look and function like an integrated body? Condic might reply: the activity is merely coordination, not true integration. This may indeed be the case, but it does not overcome reasonable doubt that it is not true integration.

Returning to the thought experiment, a critic might reply that if head and body can be separated and both continue to constitute proper parts of the same living human individual, then the argument proves too much. So long as a part manifests some internal organization, it remains part of the whole. But no one would argue that an amputated leg or arm maintained ex vivo remains a constitutive part of the one from whom it is cut and consequently is due the respect due to a human being.

I agree that John’s amputated leg and arm are not parts of John, other than in the sense that both came from him. But for two reasons I do not think it follows that the body from the neck down is not John and hence not due the respect due to John. First, for defenders of the existence of a rational soul, the soul is that which organizes both head and body, but is reducible to neither. Why cannot this nonmaterial principle organize living parts of the same body that are separated? Khushf replies that, at least for defenders of the biological definition of death, it is because this would imply the absurd conclusion that a biologically individuated organism can be divided into two (Khushf, 2010, 351). But the SCI scenario has already challenged our ordinary ideas about individuality. Pace Condic, it is not unreasonable to conclude that the head and body of the SCI patient belong—in both an organismal and metaphysical sense—to the same individual. If while separated the body segment ceased to express holistic integration and the head continued to exhibit consciousness, we would doubtlessly consider the SCI patient still alive. If the head “died” and the remaining body continued to exhibit living holistic properties, it is not obvious why we should not likewise consider the patient as living in a disabled condition.

Second, although individual limbs, even if expressive of some internal organization, should not be considered personal, it only follows that an entire living body severed from the head is impersonal if we conclude in advance that a functional brain is necessary for human life. But this, of course, is what needs to be demonstrated. One might spin what I am saying into a reductio by asking how large a body segment must be before it moves from the category of mere part to that of constitutive part. And I concede that, when swimming in these murky waters, finding a clear line is very difficult. But the persistent doubt that compromises my moral certainty arises not from the size of a body segment, but from the multiplicity and complexity of unified functions that a body expresses. When functions such as respiration, nutrition, homeostasis, temperature control, detoxification, febrile response, energy balance, and recovery from wounds, sepsis, and congestive heart failure, are all expressed by a body from the neck to the toes, I doubt that that body is a corpse. Saying this only reemphasizes the importance of developing useful criteria for distinguishing between complex coordination in parts and holistic integration in a human whole, something that this paper does not provide, but that participants on all sides of the BD debate would greatly value.

A Philosopher’s Question to Scientists

If we could gather all the organs of a body from the neck down and keep them alive in separate cultures in a laboratory, and then artificially bring them together analogous to the way they exist in a human body, could this artifactual organic body be made to express the complexity and multiplicity of organized function that we see exhibited in BD bodies, where with relatively little external assistance all the parts appear to be working for the good of the whole? ²⁰ A wide consensus of informed members of the scientific community would assist in overcoming reasonable doubts.

V. A FINAL THOUGHT ON THE WIDER BD DEBATE

Some suppose that, given the global consensus on brain death, the burden of proof rests with those who argue that BD individuals are not dead to demonstrate beyond reasonable doubt that they are alive. This is a mistake. No consensus on why brain death is human death existed before the early 1980s, and within a decade, evidence was produced credibly challenging the reasoning underlying the consensus. When Shewmon presented his evidence to the PCBE in 2007, the members quickly abandoned the reasoning. Left with an unsupported conclusion and what it referred to as a “plausible intuition” that a BD body is no longer a whole organism, the PCBE developed a new rationale (PCBE, 2008, 60; cf. 59). I have argued elsewhere that it is unsatisfactory (Brugger, 2013). Whether or not I am correct, no one can claim that a wide consensus exists in favor of the PCBE’s rationale. So although the medical community has presumed for four decades that BD bodies are corpses, and transplant experts have acted in good faith on that presumption, the presumption has never been grounded in an accepted philosophically defensible set of reasons.

The moral principle I am defending is that we should not treat as a corpse what for all we know might be a living human being. The doubt of fact in the brain death debate relates directly to the sanctioning of organ harvesting. The moral certitude necessary to sanction this behavior is that BD bodies are dead. The burden of proof, therefore, lies with those who argue that some apparent expression of holistic organization (or integrative somatic activity) is not a true expression. If one has reasonable doubt as to whether this is the case, then one thinks it might be a true expression and the individual might be alive. ²¹

VI. CONCLUSION

According to the biological definition of death, BD individuals either are or are not dead. Although this essay does not argue that we presently can be certain they are alive, consistently observed signs of complex functioning in the bodies of ventilated BD bodies raise a reasonable doubt against the conclusion that they are dead.

Condic and Grisez-Lee propose the two strongest arguments that they are dead. Condic argues that because all the activities manifested in BD bodies are also observed in individual body parts ex vivo, BD bodies cannot be wholes; and Grisez-Lee argue that because BD individuals have lost the radical capacity for sentience, they cannot be human beings. The first argument is doubtful because the premise does not entail the conclusion. The second is doubtful because a conscious nonrational individual and a conscious nonsentient individual are more likely to be alive than dead.

Since the best evidence does not dispel the doubt that ventilated BD bodies are dead; and since we should not treat as corpses what for all we know might be living human beings, we have an obligation to treat BD individuals as if they were living human beings. ²²