Death

3. Death as the cessation of life

The most popular analysis of the concept of death is expressed by (D1). One problem with (D1), however, is its obscurity. There is great controversy about the concept of life. Some claim that to be alive is to be able to engage in life processes, such as nutrition, respiration, and reproduction. Others say that life requires the presence of a soul or some other animating substance. Still others define life by appeal to the notion that living things are able to resist the force of entropy. A number of incompatible accounts of the nature of life have been proposed, but none enjoys universal acceptance. Hence, it is not entirely clear that we know precisely what we mean when we say that something is alive. Since in (D1) death is defined by appeal to the concept of life, (D1) inherits the obscurity of the concept of life.

Furthermore, (D1) seems to be inconsistent with certain empirical facts. One fact concerns suspended animation. Freezing, drying and certain other procedures may be used to arrest the life functions of formerly living entities. Viruses, bacteria and other micro-organisms are placed in suspended animation in laboratories as a matter of course. Sperm, eggs and blastulas of horses, cows and even human beings may be held in this state for months or years. Since all the life functions of such entities have been suspended, it seems that they have ceased to live. But since they can return to life again later, it seems that they have not died. (D1) therefore fails, since it implies that when such organisms go into suspended animation, they die.

In light of this difficulty with suspended animation, it might appear that it would be better to define death not as the mere cessation of life, but as the permanent cessation of life:

If an organism goes into suspended animation but will later return to life, (D3) implies that it has not died as its loss of life was not permanent. Thus, (D3) seems to be an improvement over (D1).

Nevertheless, (D3) is still problematic. Suppose two similar organisms go into suspended animation at some time. Suppose one is later brought back to life, whereas the other is not. Then during the period when both were in suspended animation, the first was not dead (since it had not permanently ceased to live) but the second was already dead (since it had permanently ceased to be alive). This may seem odd, since the two organisms might have been cell-for-cell duplicates during the period of suspended animation, yet according to (D3) one was already dead and the other was not. This shows that (D3) conflicts with the intuitively plausible notion that the life and death of an organism depends upon the intrinsic character of that organism. Thus none of the traditional analyses of the concept of death is definitively correct. The fundamental question about death remains unanswered: we do not know precisely what death is.