“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.”

“Neel takes a sharp breath and I know exactly what it means. It means: I have waited my whole life to walk through a secret passage built into a bookshelf.”

“Have you ever played Maximum Happy Imagination?""Sounds like a Japanese game show."Kat straightens her shoulders. "Okay, we're going to play. To start, imagine the future. The good future. No nuclear bombs. Pretend you're a science fiction writer."Okay: "World government... no cancer... hover-boards.""Go further. What's the good future after that?""Spaceships. Party on Mars.""Further.""Star Trek. Transporters. You can go anywhere.""Further.""I pause a moment, then realize: "I can't."Kat shakes her head. "It's really hard. And that's, what, a thousand years? What comes after that? What could possibly come after that? Imagination runs out. But it makes sense, right? We probably just imagine things based on what we already know, and we run out of analogies in the thirty-first century.”

“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.”

“Hale." Kat sighed. "The headmaster's car? Really? That's not to cliched for you?"What can I say?" He shrugged. "I'm an old-fashioned guy. Besides, it's a classic for a reason." He leaned against the window. "It's good to see you, Kat."Kat didn't know what to say. It's good to see you, too? Thanks for getting me kicked out? Is it possible you've gotten even hotter? I think I might have missed you?”

“The suburban mind cannot comprehend the emergent complexity of a New York sidewalk.”

“Listen very carefully... listen to everyone and don't say much and think about what they say and how they say it and watch their eyes... it becomes like a big jigsaw, but you're the only one who can see all the pieces. You'll know what they want you to know, and what they don't want you to know, and even what they think no one knows.”