Hickam's dictum is a counterargument to the use of Occam's razor in the medical profession. While Occam's razor suggests that the simplest explanation is the most likely, implying in medicine that diagnosticians should assume a single cause for multiple symptoms, one form of Hickam's dictum states: "A man can have as many diseases as he damn well pleases." The principle is attributed to John Hickam, MD. When he began saying this is uncertain. In 1946 he was a housestaff member in medicine at Grady Memorial Hospital in Atlanta. Hickam was a faculty member at Duke University in the 1950s, and was later chairman of medicine at Indiana University from 1958 to 1970. He died at age 55 in 1970. 
- See, e.g., "Hickam's Dictum versus Occam's Razor: A Case for Occam." W. Bradley Fields, MD, University of Michigan Health System, Ann Arbor, MI (2005) ( )
- Wallace T. Miller, "Letter From the Editor: Occam Versus Hickam", Seminars in Roentenology, vol. 33 (3), 1998-07, page 213, attributed to "an apocryphal physician named Hickam"
- Journal of Neuro-Ophthalmology: September 2002 - Volume 22 - Issue 3 - pp 240-246 ( )