Dawson pointed out that while this visual memory is a rare gift, Wiltshire's art is something he has had to work at. "The exceptional talent not only comes from the natural inborn abilities but also spending hours and hours practicing that skill."
But everyday life for Wiltshire can pose difficulties. Now 37, he still lives with his mother. His sister runs his business. Wiltshire's autism makes relationships and communication very hard, but he appears to realize the happiness his drawings bring to people.
"They say to me, they use that word genius. In Russian, 'genii.' I remember that sometimes," he said. When asked by ABC News' Nick Watt, "Do you think you're a genius?" Wiltshire offers a sheepish smile and the answer, "Yeah, I am. Of course."
A genius -- and an inspiration to others with autism.
"When people like Stephen can develop their talents, and even use those talents to have a profession where they can earn money, this is a great role model for other young people with autism who can hopefully look up to people like Stephen and say, you know, 'I can do that too,'" Dawson said.
Learn more about disabled people with extraordinary abilities at the Wisconsin Medical Society's Savant Syndrome page.