Pellegrino has argued that end-of-life decisions should be based upon the physician’s assessment of the effectiveness of the treatment and the patient’s assessment of its benefits and burdens. This would seem to imply that conditions for medical futility could be met either if there were a judgment of ineffectiveness, or if the patient were in a state in which he or she were incapable of a subjective judgment of the benefits and burdens of the treatment. I argue that a careful theory of futility would deny that physicians have the moral warrant to withhold treatments from patients unilaterally on the basis of a judgment that the individual patient lacks the cognitive substrate to appreciate the treatment as a benefit or a burden. However, such a careful theory would permit some cases of the unilateral withholding of treatments that, to a reasonable degree of medical certitude, would be ineffective. I call this the "circumspect" view. I argue that medicine should adopt this circumspect view – one that situates the medical futility debate squarely within a philosophy of medicine. Those who would deny that one could distinguish objective from subjective medical judgments challenge the circumspect view. I defend the circumspect view on the basis of a previously neglected aspect of the philosophy of medicine –an examination of varieties of medical judgment. I will then offer some practical applications of this theory in clinical practice.