British-born journalist and author of books on paranormal subjects (1947-2001). In his 1991 book Hungry Ghosts he described certain disillusioning experiences with mediumistic channelling.  

French astronomer and psychical researcher (1842-1925), notable for his writings on mediumship and psychic phenomena, including case collections. 

Ana Borges Flores is a lawyer by training who has moved into psychology and psi research, and is developing experimental tests in quantum theory.

Swiss psychologist (1854-1920) noted for his book From India to the Planet Mars, a psychological study of the trance medium Hélène Smith. 

Academic psychologist and psi investigator (1934-2010) whose many books covered topics such as transpersonal psychology, dreams and survival of death.

Francis Bacon (1561-1626), a pioneer of science, was widely believed to have been sceptical of psychic phenomena. In fact he believed some were real, but opposed their investigation on theological grounds. 

British psychologist and prominent psi sceptic working at Goldsmiths, University of London. French frequently appears in the media as a critic of psychic claims, but has also carried out laboratory psi research.

American critic of parapsychology and paranormal claims (1914-2010), considered to have been a founding member of the modern sceptical movement. 

Hamlin Garland (1860-1940) was an American writer and psychical researcher, noted for his investigation of the Buried Crosses episode.

British psychologist, well-known in the psi research community for his investigations and commentary, notably in the areas of poltergeists, mediumship and the early history of psychical research.