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Symposium on the Philosophy of Biology Death is a Statistical Matter Buffalo, NY, USA, Saturday October 14th, 2006. Werner CEUSTERS Center of Excellence in Bioinformatics and Life Sciences, and National Center for Biomedical Ontology, University at Buffalo, NY, USA. Referent Tracking.
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Symposium on the Philosophy of BiologyDeath is a Statistical MatterBuffalo, NY, USA,Saturday October 14th, 2006 Werner CEUSTERS Center of Excellence in Bioinformatics and Life Sciences, and National Center for Biomedical Ontology, University at Buffalo, NY, USA
Referent Tracking • Purpose: make clear to what entities in reality data in information systems (IS) refer to • E.g. in EHR: references to a patient, his body parts, presenting symptoms, medical interventions, ... • Method: • assign to each relevant entity in reality a unique ID and use that ID in the IS; • keep a globally accessable inventory of the assignments to particulars, and use a realism-based ontology for reference to universals and defined classes; • formulate descriptions in an IS in such a way that they directly mirror the relationships that obtain between the referents.
instance-of at t1 inst-of at t2 #1 #10 person instance-of at t1 inst-of at t2 #2 #20 liver instance-of at t1 inst-of at t2 #3 #30 tumor instance-of at t1 inst-of at t2 #4 #40 treating clinic #5 #5 instance-of at t1 inst-of at t2 device #6 #6 For example ‘John Doe’s liver tumor was treated with RPCI’s irradiation device’ ‘John Doe’s ‘John Smith’s liver liver tumor tumor was treated was treated with with RPCI’s RPCI’s irradiation device’ irradiation device’
Key question for this presentation • On what entity should I stick an ID when in a description the word ‘death’ is used ? • This one? Remind: ‘referent’ tracking, not ‘reverend’ tracking
More precisely ... (1) • What, if anything at all, are the entities we refer to when using the terms ... • For these entities that are dependent, what do they depend on ? t ‘death’ ‘living’ ‘dying’ ‘being dead’
More precisely ... (2) • What is it thus that ‘is alive’ or ‘is death’ ? • person versus organism • Is being dead equal to non-existence ? • does a corpse preserve the identity of the dead person/organism • How many – or which - parts of an organism must be dead for the organism to be dead ? • Brain death, cardiopulmonary death • Cell death • What are the criteria for something to be dead, or for something not to exist anymore ?
My claim • In trying to answer these questions, one inevitably bumps into issues of • Quantification over multiple entities • Drawing fiat boundaries • And thus, per (by?) definition, issues of probability and statistics.
Credits to … • David B. Hershenov. • “The Definition of Death”. Metaphysics and Medicine Conference (published ?) • "Do Dead Bodies Pose a Problem for the Biological Account of Identity?" Mind 114, January 2005. • "The Metaphysical Problem of Intermittent Existence and the Possibility of Resurrection." Faith and Philosophy. January 2003. Very good overview of the literature
Death from a population perspective Getting referent tracking right on ‘death’ will lead to better mortality and incidence statistics, and more accurate prediction
Death prediction:People clearly worry about their death 1st hit for “death” in Google: www.deathclock.com
Life expectancies Is there an upper bound ?
A wealth of risk factors, a wealth to track ... • Maternal age alone is a risk factor for infant death, with mortality rates highest among infants born to young teens (less than 16 years) and to older mothers (44 years or older). Pillai VK, Bandyopadhyay S. Age effects on infant mortality controlling for race: a meta-analytical study. Health Care Women Int. 1997 Mar-Apr;18(2):115-26. • Fainting during childhood, and whether a teen is going through the male or female changes of puberty, are among the factors that predict whether a genetic defect will suddenly stop the teen's heartbeat. Hobbs et.al. Risk of Aborted Cardiac Arrest or Sudden Cardiac Death During Adolescence in the Long-QT Syndrome.JAMA. 2006;296:1249-1254.
Of course, they mean ‘activities’ Sufficient, but hardly necessary. Epistemic problem: how can we ever know ? “Death” in the Gene Ontology • Name: death • Last updated: 2001-03-30 04:29:44.0 • Definition: A permanent cessation of all vital functions: the end of life; can be applied to a whole organism or to a part of an organism.
Seems more to describe ‘dying’ than ‘death’, or the initiation of a process leading to death But if this happens, what is then the result ? ‘Cell death” in the Gene Ontology • The specific activation or halting of processes within a cell • so that its vital functions markedly cease, • rather than simply deteriorating gradually over time, • which culminates in cell death.
James Bernat’s description of death • “the permanent cessation of the critical functions of the organism as a whole” • “the organism as a whole is an old biological concept that refers…to that set of vital functions of integration, control and behavior…and operate in response to demands from the organism’s internal and external milieu to support life and to maintain its health. Implicit in the concept is the primacy of the functional unity of the organism.” • ‘any account of death must respect five assumptions, one of which is that “Death is irreversible”.’ Bernat, James L. “A Defense of the Whole-Brain Concept of Death.” Hastings Center Report. 21. no. 2. (1998) pp. 14-23.
Lawrence Becker’s description of death • “a human organism is dead when, for whatever reason, the system of those reciprocally dependent processes which assimilate oxygen, metabolize food, eliminate wastes, and keep the organism in relative homeostasis are arrested in a way which the organism cannot reverse” Becker, L.C. “Human Being: The Boundaries of the Concept.” Philosophy and Public Affairs. 1975, pp. 353-4.
Problems with these accounts (1) • “Since ‘irreversibility’ adjusts to the times, the proposed statute can incorporate new clinical capabilities. Many patients declared dead fifty years ago because of heart failure would have not experienced an ‘irreversible cessation of circulatory and respiratory functions’ in the hands of a modern hospital.” The President’s Commission for the Study of the Ethical Problems in Medicine, Biomedical and Behavioral Research in their influential 1981 “A Report of the Medical, Legal and Ethical Issues in the Determination of Death.” p. 76. • But: “Imagine someone’s heart and lungs stop and his condition can’t be reversed but then a few moments later the technological breakthrough occurs which can then reverse his condition. Then with the invention or discovery he has come back from the dead despite this change in his state failing to be correlated to any significant change in his body. ” David B. Hershenov. “The Definition of Death”. Metaphysics and Medicine Conference
Problems with these accounts (2) • Cryptobiotic organisms • Cease functioning in some environment and are “revitalised” again in another one • The drowning surfers: • Pulmonary and cardiac stop until thrown on the beach afters which the organs start to function again • Refunctioning only because of resuscitation
David Hershenov’s 1st proposal • “irreversibility” should be dropped and replaced by the concept of “auto-reversion,” i.e.: any organism is dead when it can’t restart its vital life processes David B. Hershenov. “The Definition of Death”. Metaphysics and Medicine Conference
On the meaning of “organism” • Bernat: “higher order” organisms • The death of a dog is similar to the death of a person • “organism” refers to a biological entity; “person” refers to a psychosocial entity • Rather “personhood” than “person” would be a universal • An organism can die, personhood can be lost Bernat, James L. “A Defense of the Whole-Brain Concept of Death.” Hastings Center Report. 21. no. 2. (1998) pp. 14-23.
Other accounts on person / organism :2 notions of “death” required (1) • Robert Veatch: • “Death is the irreversible loss of that which is essentially significant to the nature of humans. Death…is not in any sense a biological statement of cessation of cellular respiration or functioning, as the term might be used in referring to the death of a plant or nonhuman animal. • When we speak of human death, we mean something radically different….we may well find it more plausible to opt for a concept focusing on the irreversible loss of the capacity for experience…rather than the irreversible loss of integrating capacity of the body…”. Veatch. Transplantation Ethics .
Other accounts on person / organism :2 notions of “death” required (2) • Jeff McMahan: • distinguishes our death from that of the human animal. • doesn’t believe that the human organism and the person are spatially coincident. • McMahan argues that we are essentially neither souls, human animals, nor persons (defined as self-conscious beings), but rather embodied "minds" (embodied beings with the capacity for consciousness); our identity is a function of the continuation of this capacity. Jeff McMahan, The Ethics of Killing: Problems at the Margins of Life (Oxford: Oxford University Press, 2002)
Death of the person & death of the human • McMahan thus contends that there are two correct conceptualizations of human death: • one for the human organism and • one for the person or, more precisely, the mind (EK, pp. 423-24). • His argument: • Our minds are not identical to our organisms; • both minds and organisms are living substances, • both die when they pass out of existence. • Thus, while you will die when your capacity for consciousness is irreversibly lost, your organism may continue to live in virtue of cardiopulmonary function until it suffers a terminal cardiac arrest (EK, p. 439). Jeff McMahan, The Ethics of Killing: Problems at the Margins of Life (Oxford: Oxford University Press, 2002)
David Hershenov’s 2nd proposal • the word “organism” needs to be dropped from the definition of ‘death’ and replaced with a term like “individual” that can allow both organisms and persons to die when vital life processes can’t be auto-reversed. • When the person ceases to be the subject of life processes due to his living body being replaced with a non-living one or because he no longer exists, then he is dead. David B. Hershenov. “The Definition of Death”. Metaphysics and Medicine Conference
Hershenov’s (short) definition • any entity is dead when it can’t restart its vital life processes • CPR and other resuscitation attempts must then be interpreted not as directly restarting the life processes, but causing the entity to restart these processes. • Otherwise: one could die several times
But ... • Suppose technology advances in such a way that we can ‘re-assemble’ a human out of different parts. • What is the status of the body before the ‘re-animation’ ? 1) What then with this guy ? 2) Tells us ‘when’ an entity is dead, but still not ‘what’ is death, i.e., what ontological entity does ‘death’ refer to. 3) Does not address the question whether something that is dead, does still exist.
Death as a boundary It is clear enough that people die when their lives end, but less clear what constitutes the ending of a person's life. Stanford Encyclopedia of Philosophy, Jan 2006
Death as a boundary B. Smith. Fiat Objects
Taxonomy of fiat and bonafide entities B. Smith. Fiat Objects
What type of boundary is ‘death’? Inner Outer Fiat ? ? Bonafide ? ?
x y z X Key question: when does an organism start and cease to exist ? t father’s sperm cell zygote mother’s ovum morula gastrula fetus person corpse ashes
Elderly persons are not alive ? Children are not alive ? Patients with total paresis are not alive ? Life: the classical view • Anything “alive” participates in: • Reproduction • Nutrition • Respiration • Irritability • Movement • Growth • Excretion
More recent thoughts • Rybicki EP, 1996. • "The phenomenon associated with the replication of self-coding informational systems", (general) • “The phenomenon associated with the replication of nucleic acids". (specific) • Dulbecco R and Ginsberg HS, 1980. Virology, p.854-855 • "Life can be viewed as a complex set of processes resulting from the actuation of the instructions encoded in nucleic acids. • In the nucleic acid of living cells these are actuated all the time; in contrast, • in a virus they are actuated only when the viral nucleic acid, upon entering a host cell, causes the synthesis of virus-specific proteins. Viruses are thus "alive when they replicate in cells, while outside cells viral particles are metabolically inert and are no more alive than fragments of DNA."
“Life” versus “being alive”/”living” • The life of continuant c1: • The processual entity composed of the processes in which c1 participates ? • allows parts of c1’s life being also parts of c2’s life if c1 and c2 engage in activities or relationships together (playing tennis) • Including the processes in which c1’s (undetached) parts participate ? (Is the beating of my heart part of my life?) • would lead to postmortal processes occurring in c1 being part of c1’s life; • then c has a life while not being alive.
Causal-dependence account of organism identity “An organism persists for as long as thearrangement of its particles is caused in an appropriate way by the activitiesof its life” Formally: For any x that is an organism at a time t and any y that exists at a latertime t*, x=y if and only if y's particles at t* are arranged as they are at t*in large part because of the activities of x's life at the last time between tand t* when that life was going on. Mackie, D. 1999. Personal Identity and Dead People, Philosophical Studies 95: 219-42.: 236f.
A counter-argument to the causal-dependence account of organism identity • Suppose ananimal dies and its remains are burnt to ashes, but one finger remains intact • (an ordinary finger, not one magically capable of growing into a completehuman being). • The lone finger's parts will be arranged as they are becauseof the activities of the animal's life when it was last going on. • The causal-dependence account thereforeappears to imply that the animal survives this adventure as a finger. I takethat to be false. Olson, ET (2004) Animalism and the Corpse Problem. Australasian Journal of Philosophy, 82 (2). pp. 265-274.
Death as outer boundary • The termination of the last process in which continuant c participated ? • From that point on, c is dead • Does c still exist ? • If at time t1 c still exists, there might come a time t2 at which c participates again in a process, • e.g. being buried • c’s life would continue without c being existent • If c does not exist from that point on, how is it possible to assign it properties that hold at a time c doesn’t exist ?
Inner temporal boundaries • Bona fide: • correspond to some physical discontinuity or intrinsic qualitative differentiation • might be: the point in the flight of the projectile at which it reaches its maximum altitude and begins its descent to earth, • the point in the process of cooling of the liquid at which it first begins to solidify, • the point in the splitting of an amoeba when one substance suddenly becomes two. • Fiat: • the boundary between the fourth and fifth minute of the race, • John’s reaching the age of three, • the scheduled time for the beginning of the meeting. B. Smith. Fiat Objects
X Death as an inner boundary ? t John being a foetus John being a child John being an adult John being a corpse John’s ashes John lives John is dead ?
Death as a fiat or bona fide boundary ? • Fiat boundaries are boundaries which owe their existence to acts of human decisionor fiat, to laws or political decrees, or to related human cognitive phenomena. • Fiat boundaries are ontologically dependent upon human fiat. • Bona fide boundariesare all other boundaries. B. Smith. Fiat Objects
The fiat view of biomedicine • Must the entire brain be dead to diagnose brain death? Doyle DJCan J Anaesth. 2006 Oct;53(10):1061. • Brain Death: Is That Dead Enough? Maurice Bernstein’s Bio-ethics discussion pages (http://www-hsc.usc.edu/~mbernste/) • ‘My reading of the relevant literature is that clinical criteria (supplemented, when appropriate, by diagnostic testing) can accurately identify a situation from which no one has ever recovered.’ anonymous prof in neurology
UK Brain Stem Dead criteria • Meeting clearly defined preconditions • clinical diagnosis compatible with BSD • totally unresponsive patient dependent on a ventilator. • absence of seizures and any limb movements except spinal reflexes • all reversible causes of coma and ventilator dependence must be excluded • all sedative drugs and neuromuscular blockers • metabolic causes of coma • Cranial nerve testing done twice by two experienced clinicians. • The patient is declared dead if, on two occasions there is no respiratory effort and there is total absence of cranial nerve activity. The time of death is legally deemed to be the time when the first set of tests was completed.
Death and death-like situations • Cortical brain death: • No consciousness • Persistent vegetative state: • person is allowed to be awake but is unaware, that is there is no contextual content to consciousness. • “Locked-out syndrome” • Destruction of thalamus without cortical destriction; • “Locked-in syndrome”: • patient virtually unable to move at all even though his level of awareness is there • Total brain death: • Brain stem death plus absence of cortical functions
Some neurological tests Charles S. Yanofsky, M.D.BEYOND BIOLOGY: INSIDE THE NEURON http://www.pneuro.com/publications/insidetheneuron/
The fiat view of Cryonics • The boundaries we draw around “life” and the “self” arearbitrary, motivated by specific interests and purposes. Life and the self have no essential reality which canbe definitively discerned, or boundaries which can be definitively marked. • Instead of having identity, we have degrees of identity, measured by some criteriasuitable to the purpose. • If the freezing preserved enough identity−critical neuralinformation, some future technology might be able to repair the tissue damage and make the frozen liveagain. Ettinger, Robert. 1965. The Prospect of Immortality. http://www.cryonics.org/contents1.html
‘The death of one is the life of another one’in a new context • Hughes proposes: • ‘a gradual redefinition of life and personal identity in terms of psychological continuity’. • ‘If, due to information loss, the reanimated do not meet athreshold of psychological continuity, they may be considered new persons.’. James J. Hughes. The Future of Death: Cryonics and the Telos of Liberal Individualism JOURNAL OF EVOLUTION AND TECHNOLOGY, Volume 6, July 2001. http://jetpress.org/volume6/death.html
The ‘transhumanist project’ • Find opportunities for enhancing the human condition and the human organism opened up by the advancement of technology. • radical extension of human life-span • eradication of disease, • elimination of unnecessary suffering, • augmentation of human intellectual, physical, and emotional capacities. • Ways in achieving this: • From a healthy lifestyle, to • Advanced technologyincluding making provisions for being cryonically suspended in case of de-animation. • Gradually replacing an organism’s cells by nano-devices. Nick Bostrom. Transhumanist Values. Review of Contemporary Philosophy, 2005, Vol. 4, May