In their day to day practice, clinicians make not only scientific judgments about the effectiveness of one intervention in comparison with another but also value judgments. Sometimes such judgments are explicit—for example, when a doctor reflects on his or her own moral views about the permissibility of abortion. In most cases, however, value judgments in medical practice are implicit in what seem, at first glance, to be “clinical” decisions.

Thus doctors may not think of themselves as making value judgments when, for example, considering what would be in an incompetent patient's best interests, weighing up whether harm to a third party is serious enough to justify a breach of patient confidentiality, or assessing quality of life in intensive care. Yet these decisions do indeed entail the making of value judgments, as …