A retarded individual who shows unusual ability in one or more specialized activitiesThe term is a misnomer. Idiot savants are rarely idiots and never wise in the full sense of the term. The idiot category, which is now abandoned, implies that these individuals have an IQ of less than twenty or twenty-five and can only reach the intellectual and social level of a two-year-old child. The idiot savant is actually of a higher grade, usually on the mildly or moderately retarded level, which are roughly equivalent to the older categories of moron and imbecile. Their “wisdom” is displayed by unexpected and often remarkable skill in a limited area of manual or mental activity, illustrating, as Anastasi (1958) points out, “the extent to which certain intellectual functions may develop independently of others.”One noted idiot savant devoted his life to the construction of ship models that were so accurately reproduced that he received recognition from the King of England. Many others have displayed special aptitude for drawing or music (Anastasi and Levee, 1960) or an amazing memory for detail—for example, one man could not only give the exact dates of all the funerals in his town for many years back, but was able to name every person who marched in the funeral procession. A common feat of idiots savants is to name the day of the week on which any date occurs in any year. They usually give the right answer in a matter of seconds. Studies of idiots savants indicate that these abilities are not natural gifts but are developed through long and single- minded practice. They probably reach a peak of perfection because they lead simple lives and are not distracted by other activities. Moreover, they are highly motivated by the recognition they receive for their unusual feats. These ideas were recently confirmed in a study of identical twins who not only solved the day-of-the-week and other problems, but usually answered in chorus.