 Early in his discussion of automatism, James (1890) includes some remarks about his intellectual development, and refers to his early study of medicine. “Epiphenomenon” has a use in this field, meaning a symptom concurrent with, but not causally contributory to, the course of a disease. Some early twentieth century dictionaries list only this meaning of the term; by mid-twentieth century, the focal philosophical meaning is standardly given. My present surmise is that the term “epiphenomenalism” came into philosophy from medicine in the late nineteenth century, possibly, though less certainly, through William James’s use of the term in his influential Principles of Psychology (1890).