Arrogance among physicians is, regrettably, common and violates the benevolent spirit of medicine-its very soul -as well the quality of medical care. The need for humility in the physician warrants greater emphasis in medical training, both in the classroom and, more critically, by example. Arrogance persists because of intersecting and mutually enhancing sociologic and psychological pressures. Regarding the sociologic elements, in earlier times, the great respect and prestige accorded physicians could foster arrogance in some. Today, physicians as a group are less likely to be idealized, but the health care system has depersonalized the doctor-patient relationship and created a kind of "system arrogance" in which the patient is seen not as a person but merely as a job to be done cost-effectively. As for psychological aspects, physicians are sometimes drawn to medicine by their unconscious concerns about illness and mortality-they become health experts in the hope of extending their own lives. Such physicians treat death as the enemy, and may practice unwarranted heroic measures. But the most critical variable in the development of arrogance is a physician's knowledge and thereby his or her power over the patient. This can delude some physicians into imagining that they are all-powerful. Seriously ill or injured patients tend to view the physician as an omnipotent parent and savior, and in this way unwittingly tempt physicians to be arrogant. The author concludes by reminding his fellow physicians that "we should not exaggerate our own importance. we are but an instrument of healing and not its source."