ILLUSION DES SOSIES

A French term proposed in 1923 by the French psychiatrist Jean Marie Joseph Capgras (18731950) and his intern Jean Reboul-Lachaux to denote what would later come to be known as "Capgras' syndrome (i.e. illusion of doubles). The expressionillusion des sosieswas inspired by the playAmphytrionby the Roman playwright Titus Maccius Plautus (250?-184 BC), in which the god Mercury takes on the identity of Sosie, one of Amphytrion's servants.

Capgras, J., Reboul-Lachaux, J. (1923). L'illusion des "sosies" dans un delire systematisé.Bulletin de la Société de Médecine Mentale, 11, 6-16.