the best life possible for him or her with treatment is of sufficiently poor quality that it is worse than no further life at all. Life is no longer considered a benefit by the patient, but has now become a burden. The same judgment underlies a request for euthanasia: continued life is seen by the patient as no longer a benefit, but now a burden. Especially in the often severely compromised and debilitated states of many critically ill or dying patients, there is no objective standard, but only the competent patient's judgment of whether continued life is no longer a benefit.
             Of course, sometimes there are conditions, such as clinical depression, that call into question whether the patient has made a competent choice, either to forgo life-sustaining treatment or to seek euthanasia, and then the patient's choice need not be evidence that continued life is no longer a benefit for him or her. Just as with decision about treatment, a determination of incompetence can warrant not honoring the patient's choice; in the case of treatment, we then
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