Death

[SunKat]

Death

Death is life's ending. Let us say that vital processes are those by which organisms develop or maintain themselves. These processes include chemosynthesis, photosynthesis, cellular respiration, cell generation, and maintenance of homeostasis. Then death is the ending of the vital processes by which an organism sustains itself. However, life's ending is one thing, and the condition of having life over is another. ‘Death’ can refer to either.

Let us add that ‘the ending of life’ is itself potentially ambiguous. On one hand it might be a process wherein our lives are progressively extinguished, until finally they are gone. On the other it might be a momentary event. This event might be understood in three ways. First, it might be the ending of the dying process—the loss of the very last trace of life. Call this ‘denouement death’. Second, it might be the point in the dying process when extinction is assured, no matter what is done to stop it. Call this moment ‘threshold death’. A third possibility is that life ends when the physiological systems of the body irreversibly cease to function as an integrated whole (defended, for example, by Belshaw 2009). Call this ‘integration death’.

Thus death can be a state (being dead), the process of extinction (dying), or one of three events that occur during the dying process. Death in all of these senses can be further distinguished from events—such as being shot with an arrow—that cause death.

The Permanence of Death

‘Death’ is also unclear in at least two ways. First, the concept of life is not entirely clear. For example, suppose we could construct a machine, the HAL 1.01, with (nearly) all of the psychological attributes of persons: would HAL 1.01 be alive? To the extent that we are puzzled about what life entails, we will be puzzled about what is entailed by the ending of life, that is, death. (For accounts of life, see Van Inwagen 1990 or Luper 2009.) Second, it seems somewhat indeterminate whether a temporary ending of life suffices for death, or whether death entails a permanent loss of life. Usually, whenever a creature's life stops, the condition is permanent; so ‘death’, as commonly used, need not be sensitive to the distinction between the temporary and permanent ending of life. Yet life may stop temporarily: a life might be suspended then revived. Or it might be restored. Life in the case of seeds and spores is suspended indefinitely. Freezing frogs and human embryos suspends their lives, too. Suppose that I were frozen and later revived: it is tempting to say that my life stops while I am frozen —I am in a state of suspended animation. But I am not dead. Now imagine a futuristic device, the Disassembler-Reassembler, that reduces me to small cubes, or individual cells, or disconnected atoms, which it stores and later reassembles just as they were before. Many of us will say that I would survive—my life would continue—after Reassembly, but it is quite clear that I would not live during intervals when my atoms are stacked in storage. I would not even exist during such intervals; Disassembly kills me. After I cease to exist, presumably I cannot be revived; nor can my vital processes be revived. If I can be Reassembled, my life would be restored, not revived. Restoration, not revival, is a way of bringing a creature back from the dead.

Assuming that creatures whose lives are suspended are not dead, but creatures who are Disassembled are dead even if later Reassembled, it might be best to say that a creature has died just when its vital processes are irreversibly discontinued, that is, when its vital processes can no longer be revived.

Death and What We Are

Death for you and me is constituted by the irreversible discontinuation of the vital processes by which we are sustained. This characterization of death could be sharpened if we had a clearer idea of what we are, and the conditions under which we persist. However, the latter is a matter of controversy.

There are three main views: animalism, which says that we are human beings (Snowdon 1990, Olson 1997, 2007); personism, which says that we are creatures with the capacity for self-awareness; and mindism, which says that we are minds (which may or may not have the capacity for self-awareness) (McMahan 2002). Animalism suggests that we persist over time just in case we remain the same animal; mindism suggests that we persist just when we remain the same mind. Personism is usually paired with the view that our persistence is determined by our psychological features and the relations among them (Locke 1689, Parfit 1984).

If we are animals, with the persistence conditions of animals, our deaths are constituted by the irreversible cessation of the vital processes that sustain our existence as human beings. If we are minds, our deaths are constituted by the irreversible extinction of the vital processes that sustain our existence as minds. And if persistence is determined by our retaining certain psychological features, then the loss of those features will constitute death.

These three ways of understanding death have very different implications. Severe dementia can destroy a great many psychological features without destroying the mind, which suggests that death as understood by personists can occur even though death as understood by mindists has not. Moreover, human beings sometimes survive the destruction of the mind, as when the cerebrum dies, leaving an individual in a persistent vegetative state. It is also conceivable that the mind can survive the extinction of the human being: this might occur if the brain is removed from the body, kept alive artificially, and the remainder of the body is destroyed (assuming that a bare brain is not a human being). These possibilities suggest that death as understood by mindists can occur even though death as understood by animalists has not (and also that the latter sort of death need not be accompanied by the former.)