Leslie Lemake only has to hear a piece of music once and he can play it back on the piano note-perfect. Yet he has never had any formal musical training, is blind and with an IQ of only 58 is typical of the majority of autistic savants, who have well-below-average intelligence quotients. If you ask Richard the route of any bus in the London district, he will give you an answer immediately. Stephen Wiltshire has exceptional artistic talents and, like both Leslie and Richard, combines this talent with a remarkable memory, and can draw buildings with complete architectural accuracy, sometimes only hours after seeing them for the first time. Other savants are able to carry out amazing mathematical computations in their heads, but cannot add up simple numbers.