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.