Notable for his books on the subject of religious skepticism, Harrison penned 50 Reasons People Give for Believing in a god; 50 Popular Beliefs that People Think are True; and several other similar works. Also a journalist and photographer, he won the 1994 Commonwealth Media Award.
He became a devoted skeptic after reading a book -- Erich von Daniken's Chariots of the Gods? Unsolved Mysteries of the Past -- that was written from quite the opposite perspective.
A philanthropist as well as a writer and skeptic, he established a childhood poverty-fighting organization called Cayman Loves Children.
He completed his undergraduate studies in anthropology and history at the University of South Florida.
He and Australian talk show host Richard Saunders are both well known for their advocacy of skepticism.