Advance Directives and Substitute Decision Making

Challenge 3: Loss of Personal Identity
There is usually an underlying continuity of interests between the current and the former selves that can be disrupted by such things as a loss of cognitive capacity which leads to someone not surviving as the same human being anymore. Whatever interests the former self had they cannot take precedence the same way another person’s interests cannot take precedence over mine in terms of what medical treatment I get.

Some might say that the loss of personhood in the current-self means that the former self has a type of a quasi-property right over the current self (which has lesser moral standing) even if you assume it is a separate person.

Challenge 4: Severance of Prudential Concern
Even if we assume the same person exists throughout an illness, we might question the existence of a continuous interest. The importance of not only present but also future and past experiences is called prudential concern. If indeed a person is changed (as they are ) from such things as severe loss of mental capacity, then the connection between the former and the current self becomes very slight. Prudential concern only exists if the current self can be said to fit into the narrative of the former-self’s understanding of herself/himself. Just as we cannot incorporate others into our prudential concern against their will, we cannot incorporate the current self in the interests of the former-self.

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