John Eric Holmes M.D. (February 16, 1930 – March 20, 2010) was an associate professor of neurology at the University of Southern California School of Medicine, an author and promoter of fantasy role-playing games, a noted fan and enthusiast of Edgar Rice Burroughs, and an American writer of non-fiction, fantasy and science fiction. His writings appeared under his full name and under variants such as Eric Holmes and J. Eric Holmes.