Derek Parfit’s view of personal identity raises questions about whether advance decisions refusing life-saving treatment should be honored in cases where a patient loses psychological continuity; it implies that these advance decisions would not be self-determining at all. However, rather than accepting that an unknown metaphysical ‘further fact’ underpins agential unity, one can accept Parfit’s view but offer a different account of what it implies morally. Part II of this article argues that contractual obligations provide a moral basis for honoring advance decisions refusing life-saving and/or life-sustaining medical treatment; advance decisions have similarities to contracts, such as life insurance policies and will-contracts, that come into effect when the psychological discontinuity is through death.

Derek Parfit’s view of ‘personal identity’ raises questions about whether advance decisions refusing life-saving treatment should be honored in cases where a patient loses psychological continuity; it implies that these advance decisions would not be self-determining at all. Part I of this paper argues that this assessment of personal identity undermines the distinction between suicide and homicide. However, rather than accept that an unknown metaphysical ‘further fact’ underpins agential unity, one can accept Parfit’s view but offer a different account of what it implies morally: that the social and legal bases for ascribing a persisting ‘personal identity’ maintain the distinction between homicide and suicide.