Advance directives and the personal identity problem.

The value and authority of advance directives such as the living will and the durable power of attorney are discussed, as well as the dangers of loss of personal identity and psychological continuity that these directives present. Differing theories of the degree of psychological continuity necessary for the preservation of personal identity are examined, concluding with the author's "compromise position" that cases of permanent unconsciousness and neurological dementia destroy some of the preconditions for personhood and thereby negate the choice between respecting the wishes of the formerly competent person and the new, different person's life because such beings are not persons at all.