Personal identity

10. Personal identity and bioethics

As the field of bioethics has developed, several central bioethical problems have been framed in terms of personal identity (see Bioethics). Issues surrounding abortion, euthanasia, and organ harvesting, for instance, are connected to questions about when we come into existence and cease to be, and worries about enhancement technologies and certain psychotropic drugs are linked to the possibility that their use might alter a patient’s identity. Facts about identity have also been invoked in considering the authority of advance directives in which a patient specifies the level of treatment they wish to receive in a foreseeable period of incapacity or incompetence. Someone in the early stages of Alzheimer’s, for example, may sign a directive instructing that no life-saving interventions be undertaken after they have become severely demented. According to the psychological continuity theory, however, since the severely demented individual is not psychologically connected to the person who signed the directive, they are not the same person as that individual. If the psychological view of identity is correct, then, there is a serious question about whether and why such directives should have authority over a later, distinct individual.

The role of personal identity in these discussions has led to reflection on whether identity - particularly metaphysical identity - is really implicated in these ethical questions, or whether they are better framed in some other way. This reflection has in turn led to some interesting work on more general questions about the connection between metaphysical and practical concerns about personal identity (e.g. DeGrazia 2005; Shoemaker 2007). Questions about the relation between the metaphysical and the practical have, in fact, been a theme throughout the philosophical discussion of personal identity, though they are not always made explicit. Locke, for instance, assumes that personal identity is intimately linked to practical judgements; Parfit complicates this connection; and Olson rejects it. Increasingly it has come to seem as if clarity on the topic of personal identity will require a systematic investigation of the way in which the practical and metaphysical aspects of personhood are (or are not) connected. There is reason to expect a great deal of exciting work on this topic.