into the patient's double. The syndrome of subjective doubles and its variants were not given the name delusional misidentification syndromes until 1981. Doubles of the self have been reported in literature even before the syndrome was named by Christodoulou. The first patient with symptoms of Capgras syndrome, another delusional misidentification syndrome, was reported in 1923 by Joseph Capgras and Jean Reboul-Lachaux. This patient, however, also experienced the delusion of subjective doubles, but the appearance of doubles of the self were not addressed until Christodoulou's article in 1978. Controversy Due to the rarity of this disorder and its similarities to other delusional misidentification syndromes, it is debated whether or not it should be classified as a unique disease. Because subjective doubles rarely appear as the only psychological symptom, it has been suggested that this syndrome is a rare presentation of symptoms of another psychological disorder. This syndrome is also not defined in the DSM-IV or ICD-10. Additionally, some researchers use varying definitions of the syndrome. While most declare that the double is a physical copy that is psychologically independent, some refer to a definition of a double as being both physically and psychologically identical. This is also known as clonal pluralization of the self, another less common delusion that is grouped with the other delusional misidentification syndromes. See also Capgras delusion Delusional misidentification syndrome Prosopagnosia Autoscopy References Psychosis Delusional disorders Psychopathological syndromes Delusions