In 1923, under the title, “The Illusion of Doubles in a Case of Systematized Delusional Insanity” (1), J. Capgras and J. Reboul-Lachaux described for the first time an interesting syndrome of non-recognition. The case was that of a persecuted and megalomanic woman in whom there existed a condition of agnostic identification without disturbance of sensory or memory images. The patient postulated a series of “doubles” replacing the various persons of her environment, even her husband and daughter being included. During the course of a few months she complained that she had been shown one thousand doubles of her daughter. The person confronted was appreciated to resemble exactly the known individual, but on account of some subjective disorder, the ability to identify her was lost and the belief in “doubles” brought forward in order to explain this state of non-recognition.