- The term deuteroscopy comes from the Greek words deuteros (second) and skopeo (I am looking at). The coiner of the term is unknown, but it was used for centuries in demonology and occultism before taking on a biomedical connotation. From 1837 onwards the German psychiatrist Friedrich Wilhelm Hagen (1814-1888) used the term deuteroscopy to denote a phenomenon that is now known as *heautoscopy (i.e. the occurrence of a *visual hallucination depicting an individual identified as oneself, even though it does not have the exact same physical characteristics). It was the French physician and mesmerist Charles Féré (1852-1907) who criticized the use of the term deuteroscopy, suggesting instead the term * autoscopy (denoting the occurrence of a visual hallucination depicting one's self). The term deuteroscopy is now only used in occultism and parapsychology, where it serves as a synonym for second sight or * clairvoyance, i.e. the ability to evoke hallucinations or other percepts considered to be veritable in nature.ReferencesFéré, Ch. (1891). Note sur les hallucinations autoscopiques ou spéculaires et sur les hallucinations altruistes. Comptes Rendues Heb-domedaires des Séances et Mémoirs de la Société de la Biologie, 3, 451-453.Fraser, J. (1707). Deuteroscopia: A brief discourse concerning second sight. Edinburgh: A. Symson.Hagen, F.W. (1837). Die Sinnestäuschungen in Bezug aufPsychologie, Heilkunde und Rechtspflege. Leipzig: Verlag von Otto Wigand.
Dictionary of Hallucinations. J.D. Blom. 2010.