Disability
In 19th and early 20th century medicine and psychology, an "idiot" was a person with a very severe mental retardation. In the early 1900s, Dr. Henry H. Goddard proposed a classification system for mental retardation based on the Binet-Simon concept of mental age. Individuals with the lowest mental age level (less than three years) were identified as idiots; imbeciles had a mental age of three to seven years, and morons had a mental age of seven to ten years. The term "idiot" was used to refer to people having an IQ below 30. IQ, or intelligence quotient, was originally determined by dividing a person's mental age, as determined by standardized tests, by their actual age. The concept of mental age has fallen into disfavor, though, and IQ is now determined on the basis of statistical distributions.
In current medical classification, these people are now said to have "profound mental retardation."
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