In situations where experience shows that a particular intervention will not benefit a patient, common sense seems to suggest that the intervention should not be used. Yet it is precisely in these situations that a peculiar ethic begins to operate, an ethic that Eddy calls “the criterion of potential benefit.” According to this ethic, “a treatment is appropriate if it might have some benefit.” Thus, the various maxims learned in medical school instruct physicians that “‘an error of commission is to (...) be preferred to an error of omission,’ or ‘when in doubt, cut it out’ or ‘if but one patient is helped, then the treatment is worthwhile.’”. (shrink)