Sketches of the Philosophy of Apparitions: Or, an Attempt to Trace Such Illusions to their Physical Causes

In this book of 1825, Samuel Hibbert (1782–1848) attempts to uncover the physical or physiological causes which might account for claims of seeing ghosts and other apparitions. Hibbert trained as a doctor, and uses anecdotal and case-study evidence to show that external physical circumstances - such as the use of stimulants, brain inflammation, hallucination during fever, or alcohol withdrawal - are most likely to be the causes of apparent sightings of supernatural phenomena. He explores th...