Great Harms from small benefits grow: How death can be outweighed by headaches

Suppose that a very large number of people, say one billion, will suffer a moderately severe headache for the next twenty-four hours. For these billion people, the next twenty-four hours will be fairly unpleasant, though by no means unbearable. However, there will be no side-effects from these headaches; no drop in productivity in the work-place, no lapses in concentration leading to accidents, no unkind words spoken to loved ones that will later fester. Nonetheless, it is clearly desirable that these billion people avoid the headaches. Even though the headaches are moderate, they are impervious to pain-killing drugs, acupuncture, transcendental meditation, and just about any other remedy. In fact, there is only one way in which the headaches can be avoided. In a remote South American village, a young woman, Agnes, is suffering from a fever. A simple dose of antibiotics will save her life, otherwise she will die. If, and only if, she dies, the billion headaches will be prevented. You just happen to be passing through the village, in full knowledge of the circumstances. Although not a doctor (and therefore not bound by codes of professional ethics, Hippocratic oaths, etc.), you possess the requisite dose of antibiotics, for which you have no other use, and which will become useless, if not used in the next two hours.