Medical ethics has traditionally been governed by two guiding,
but sometimes conflicting, principles—autonomy and benevolence.
These principles provide the rationale for the two most commonly used
standards for medical decisionmaking—the Substituted Judgment
Standard shows our concern for autonomy, whereas the Best Interest
Standard shows our commitment to benevolence. Both standards are
vulnerable to criticisms. Further, the principles can seem to offer
conflicting prescriptions for action. The criticisms and conflict
figure prominently in discussion of advance directive decisionmaking
and Alzheimer's disease. After laying out each of the current
standards and its problems, with Alzheimer's issues as my central
concern, I offer a new standard that avoids the problems while honoring
our concerns for both autonomy and benevolence.