Savant.

Savant is a special ability that only 52 (or more) people have. It is when you have excellents in a curtain thing, like maths, writing e.g.
Gorge Finn is one of these 52 people that have it. But he also has an autistic condition. He has a child like voice while he is answer his questions. He is amazing at calendar and weather questions. Someone will tell him a date for example 19/08/1988 and then he will tell you the day of the week on that curtain date.