“They say Shakespeare invented the internal monologue." Oh, I am very familiar with the internal monologue.”

“Our books still do not require batteries. But I am no fool. It is a slender advantage.”

“Then: I google "time-series visualization" and start work on a new version of my model, thinking that maybe I can impress her with a prototype. I am really into the kind of girl you can impress with a prototype.”

“Neel cuts in: "Where'd you grow up?""Palo Alto," she says. From there to Stanford to Google: for a girl obsessed with the outer limits of human potential, Kat has stayed pretty close to home. Neel nods knowingly. "The suburban mind cannot comprehend the emergent complexity of a New York sidewalk.""I don't know about that," Kat says, narrowing her eyes. "I'm pretty good with complexity.""See, I know what you're thinking," Neel says, shaking his head."You're thinking it's just an agent-based simulation, and everybody out here follows a pretty simple set of rules"-- Kat is nodding--"and if you can figure out those rules, you can model it. You can simulate the street, then the neighborhood, then the whole city. Right?""Exactly. I mean, sure, I don't know what the rules are yet, but I could experiment and figure them out, and then it would be trivial--" "Wrong," Neel says, honking like a game-show buzzer. "You can't do it. Even if you know the rules-- and by the way, there are no rules--but even if there were, you can't model it. You know why?"My best friend and my girlfriend are sparring over simulations. I can only sit back and listen. Kat frowns. "Why?""You don't have enough memory.""Oh, come on--""Nope. You could never hold it all in memory. No computer's big enough. Not even your what's-it-called--""The Big Box.""That's the one. It's not big enough. This box--" Neel stretches out his hands, encompasses the sidewalk, the park, the streets beyond--"is bigger."The snaking crowd surges forward.”

“So I guess you could say Neel owes me a few favors, except that so many favors have passed between us now that they are no longer distinguishable as individual acts, just a bright haze of loyalty. Our friendship is a nebula.”

“This girl has the spark of life. This is my primary filter for new friends (girl- and otherwise) and the highest compliment I can pay. I've tried many times to figure out exactly what ignites it -- what cocktail of characteristics come together in the cold, dark cosmos to form a star. I know it's mostly in the face -- not just the eyes, but the brow, the cheeks, the mouth, and the micromuscles that connect them all.Kat's micromuscles are very attractive.”

“I'm going to put the moves on her,' he says gravely. 'Things might get weird.' He says it like a commando setting up a midnight raid. Like: Sure, this is going to be extraordinarily dangerous, but don't worry. I've done it before.”