Esquirol's Definition of Illusons

   In 1845 the French alienist Jean-Etienne Dominique Esquirol (1772-1840) defined illusions as follows: "In illusions ...the sensibility of the nervous extremities is altered: it is exalted, enfeebled, or perverted. The senses are active, and the actual impressions solicit the reactions of the brain. The effects of this reaction being submitted to the influence of the ideas and passions which control the reason of the insane, they deceive themselves in respect both to the nature and cause of their actual sensations."

   References

   Esquirol, J.-E.D. (1965). Mental maladies. A treatise on insanity. A facsimile ofthe English edition of1845. Translated by Hunt, E.K. New York, NY: Hafner Publishing Company.