“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.”

“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.”

“If this sounds impressive to you, you’re over thirty.”

“But I kept at it with the help-wanted ads. My standards were sliding swiftly. At first I had insisted I would only work at a company with a mission I believed in. Then I thought maybe it would be fine as long as I was learning something new. After that I decided it just couldn't be evil. Now I was carefully delineating my personal definition of evil.”

“Maybe I'll just go ahead and buy her the Tufte book. I'll bring it wrapped in brown paper. Wait- is that weird? It's an expensive book. Maybe there's a low-key paperback edition. I could buy it on Amazon. That's stupid, I work at a bookstore. (Could Amazon ship it fast enough?)”

“I walk alone in the darkness and wonder how a person would begin to determine the circumference of the earth. I have no idea. I’d probably just google it.”