Our brains work in complex and strange ways.There are some people who can calculate the day of the week for any given date in 40,000 years, but who cannot add two plus two.Others can perform complex classical piano pieces after hearing them once, but they cannot read or write.
Dr.J.Langdon Down first described this condition in 1887.He called these people idiot savants.An idiot savant is a person who has significant mental impairment (损伤) , such as in autism ( 孤独症，自闭症) or retardation.At the same time, the person also exhibits some extraordinary skills, which are unusual for most people.The skills of the savant may vary from being exceptionally gifted in music or in mathematics, or having a photographic memory.
One of the first descriptions of a human who could calculate quickly was written in 1789 by Dr.Benjamin Rush, an American doctor.His patient, Thomas Fuller, was brought to Virginia as a slave in1724.It took Thomas only 90 seconds to work out that a man who has lived 70 years, 17 days, and 12 hours has lived 2,210,500,800 seconds.Despite this ability, he died in 1790 without ever learning to read or write.
Another idiot savant slave became famous as a pianist in the 1860s.Blind Tom had a vocabulary of only 100 words, but he played 5 ,000 musical pieces beautifully.
In the excellent movie Rain Man, made in 1988 and available on video cassette, Dustin Hoffman plays an idiot savant who amazes his brother played by Tom...
