something is wrong . . . when we treat formerly competent patients as if they were never competent. Someone who makes a prior directive sees herself as the unified subject of a human life. She sees her concern for her body, her goals, or her family as transcending her incapacity. . . . One . . . component of treating persons with respect [is] that we view them as they view themselves. . . . To do this, we must not ignore their prior choices and values.
