This might be the best metaphor I have heard about a person’s brain, ever. Jon Stewart on Stephen Colbert:
“[The whole show] depends on Stephen’s ability to process information as this other person,” says Stewart. “I’ve seen talk-show hosts who can’t do that for real. … And then you watch Colbert and it’s like the first time you use broadband: ‘How the fuck did that happen?’ He’s rendering in real time.”
From the Vanity Fair piece, which is good.