This chapter looks at the history of medicine from the point of view of the diseased and distressed patient; it seems likely that Hippocrates and Galen might well have provided valuable advice, hope, and comfort. Medical theory and practice have changed so profoundly since the end of the nineteenth century that the most knowledgeable physician of that era would be mystified by the diagnostic and therapeutic techniques of twenty-first century medicine. With the development of medical instruments and laboratory tests, physicians could diagnose disease by supposedly objective techniques, rather than the patient's subjective account of symptoms. The pioneers of experimental therapeutics promised that laboratory science would explain the basic physiological principles of health, disease, and the action of remedies. When epidemiologists look at the rise and fall of diseases in a global setting over long periods of time, they provide a perspective quite different from that available to patients and practicing physicians.