Someone asked Tommy Edison (previously at Neatorama) how much he understands about vision. He’s been blind since birth, so it’s a foreign concept to him, but he’s interacted with sighted people enough to know that we do things that make no sense to him.
Sure, you can explain how stereoscopic vision works to give us depth perception, but never having been able to see it in action, he can’t wrap his head around it. I was a little surprised he didn’t mention colors, but he made a video about colors once, and seems to associate color with different smells. As always, Edison is cheerful, honest, and always ready to make a wisecrack. -via Digg