with three-page list of law cases cited. He enjoyed debunking doubtful history and pseudoscientific claims about the supernatural. He conducted extensive research for what was to be a book on magic, witchcraft and occultism, though only the first chapter, "The Unwritten Classics" (March 1947), was published in the Saturday Review of Literature. By May 1976, concerned with what Paul Kurtz described as "an enormous increase in public interest in psychic phenomena, the occult and pseudoscience," de Camp joined the newly formed Committee for the Scientific Investigation of Claims of the Paranormal along with astronomers George Abell, Bart Bok, and Carl Sagan; philosophers Brand Blanshard, Antony Flew, Sidney Hook, and Ernest Nagel; authors Isaac Asimov, Daniel Cohen, Charles Fair, Martin Gardner, and Phillip J. Klass; psychologists Ray Hyman and B.F Skinner; and magician James Randi. Despite being a long-time writer of fantasy, de Camp did not believe in ghosts in the supernatural sense. His ghosts dwelt only in his mind as memories of his parents. His mother, he wrote in a New York Times Magazine article, died of an overdose of faith healing. When considering claims of UFO sightings, astrology, and other subjects considered moot by the scientific community, de Camp would address the circular logic expressed by enthusiasts by insisting on first-hand, unbiased, measurable data to back up the claims. "In the history of cultism," de Camp said in a Science News interview, "one is always experiencing a feeling of deja vu." He explained how ancient civilizations produced structures and architecture that many considered to be impossible for them, such as the Pyramids of Ancient Egypt. Works in this area include Lost Continents, Citadels of Mystery, and The Ancient Engineers. Some others of his many and wide-ranging nonfiction works were The Great Monkey Trial (about the Scopes Trial), The Ragged Edge of Science, Energy and Power, The Heroic Age of American Invention, The Day of the Dinosaur (which argued, among other things, that evolution took hold after Darwin because of the Victorian interest spurred by recently popularized dinosaur remains, corresponding to legends of dragons), Great Cities of the Ancient World and The Evolution of Naval Weapons (a United States government textbook). Published in the July 1938 issue of Astounding Science Fiction, "Language for Time Travelers" won de Camp the first non-fiction readership monthly honor awarded in the magazine for his exploration of the communication difficulties for time travelers as pronunciation