It didn't start out here. Not with the scramblers or Rorschach, not with Big Ben or Theseus or the vampires. Most people would say it started with the Fireflies, but they'd be wrong. It ended with all those things.

For me, it began with Robert Paglino.

At the age of eight, he was my best and only friend. We were fellow outcasts, bound by complementary misfortune. Mine was developmental. His was genetic: an uncontrolled genotype that left him predisposed to nearsightedness, acne, and (as it later turned out) a susceptibility to narcotics. His parents had never had him optimized. Those few TwenCen relics who still believed in God also held that one shouldn't try to improve upon His handiwork. So although both of us could have been repaired, only one of us had been.

I arrived at the playground to find Pag the center of attention for some half-dozen kids, those lucky few in front punching him in the head, the others making do with taunts of mongrel and polly while waiting their turn. I watched him raise his arms, almost hesitantly, to ward off the worst of the blows. I could see into his head better than I could see into my own; he was scared that his attackers might think those hands were coming up to hit back, that they'd read it as an act of defiance and hurt him even more. Even then, at the tender age of eight and with half my mind gone, I was becoming a superlative observer.

But I didn't know what to do.

I hadn't seen much of Pag lately. I was pretty sure he'd been avoiding me. Still, when your best friend's in trouble you help out, right? Even if the odds are impossible—and how many eight-year-olds would go up against six bigger kids for a sandbox buddy? — at least you call for backup. Flag a sentry. Something.

I just stood there. I didn't even especially want to help him.

That didn't make sense. Even if he hadn't been my best friend, I should at least have empathized. I'd suffered less than Pag in the way of overt violence; my seizures tended to keep the other kids at a distance, scared them even as they incapacitated me. Still. I was no stranger to the taunts and insults, or the foot that appears from nowhere to trip you up en route from A to B. I knew how that felt.

Or I had, once.

But that part of me had been cut out along with the bad wiring. I was still working up the algorithms to get it back, still learning by observation. Pack animals always tear apart the weaklings in their midst. Every child knows that much instinctively. Maybe I should just let that process unfold, maybe I shouldn't try to mess with nature. Then again, Pag's parents hadn't messed with nature, and look what it got them: a son curled up in the dirt while a bunch of engineered superboys kicked in his ribs.

In the end, propaganda worked where empathy failed. Back then I didn't so much think as observe, didn't deduce so much as remember—and what I remembered was a thousand inspirational stories lauding anyone who ever stuck up for the underdog.

So I picked up a rock the size of my fist and hit two of Pag's assailants across the backs of their heads before anyone even knew I was in the game.

A third, turning to face the new threat, took a blow to the face that audibly crunched the bones of his cheek. I remember wondering why I didn't take any satisfaction from that sound, why it meant nothing beyond the fact I had one less opponent to worry about.

The rest of them ran at the sight of blood. One of the braver promised me I was dead, shouted "Fucking zombie!" over his shoulder as he disappeared around the corner.

Three decades it took, to see the irony in that remark.

Two of the enemy twitched at my feet. I kicked one in the head until it stopped moving, turned to the other. Something grabbed my arm and I swung without thinking, without looking until Pag yelped and ducked out of reach.

"Oh," I said. "Sorry."

One thing lay motionless. The other moaned and held its head and curled up in a ball.

"Ohshit," Pag panted. Blood coursed unheeded from his nose and splattered down his shirt. His cheek was turning blue and yellow. "Ohshit oh shit oh shit…"

I thought of something to say. "You all right?"

"Oh shit, you—I mean, you never…" He wiped his mouth. Blood smeared the back of his hand. "Oh man are we in trouble."

"They started it."

"Yeah, but you—I mean, look at them!"

The moaning thing was crawling away on all fours. I wondered how long it would be before it found reinforcements. I wondered if I should kill it before then.

"You'da never done that before," Pag said.

Before the operation, he meant.

I actually did feel something then—faint, distant, but unmistakable. I felt angry. "They started—"

Pag backed away, eyes wide. "What are you doing? Put that down!"

I'd raised my fists. I didn't remember doing that. I unclenched them. It took a while. I had to look at my hands very hard for a long, long time.

The rock dropped to the ground, blood-slick and glistening.

"I was trying to help." I didn't understand why he couldn't see that.

"You're, you're not the same," Pag said from a safe distance. "You're not even Siri any more."

"I am too. Don't be a fuckwad."

"They cut out your brain!"

"Only half. For the ep—"

"I know for the epilepsy! You think I don't know? But you were in that half—or, like, part of you was…" He struggled with the words, with the concept behind them. "And now you're different. It's like, your mom and dad murdered you—"

"My mom and dad," I said, suddenly quiet, "saved my life. I would have died."

"I think you did die," said my best and only friend. "I think Siri died, they scooped him out and threw him away and you're some whole other kid that just, just grew back out of what was left. You're not the same. Ever since. You're not the same."

I still don't know if Pag really knew what he was saying. Maybe his mother had just pulled the plug on whatever game he'd been wired into for the previous eighteen hours, forced him outside for some fresh air. Maybe, after fighting pod people in gamespace, he couldn't help but see them everywhere. Maybe.

But you could make a case for what he said. I do remember Helen telling me (and telling me) how difficult it was to adjust. Like you had a whole new personality, she said, and why not? There's a reason they call it radical hemispherectomy: half the brain thrown out with yesterday's krill, the remaining half press-ganged into double duty. Think of all the rewiring that one lonely hemisphere must have struggled with as it tried to take up the slack. It turned out okay, obviously. The brain's a very flexible piece of meat; it took some doing, but it adapted. I adapted. Still. Think of all that must have been squeezed out, deformed, reshaped by the time the renovations were through. You could argue that I'm a different person than the one who used to occupy this body.