PHYSICIANS must understand the scientific basis of medicine and be able to apply that understanding to the practice of medicine. They must have sufficient knowledge of the structure and function of the body (as an intact organism) and its major organ systems and of the molecular, cellular, and biochemical mechanisms that maintain the body’s homeostasis in order to comprehend disease and to incorporate wisely modern diagnostic and therapeutic modalities in their practice. They must engage in lifelong learning to remain current in their understanding of the scientific basis of medicine.