"What is your name?"
"When were you born?"
"April 7th, 2014."
"What is the date?"
"August 23, 2041."
"What is your password?"
It all began twenty years ago, when we were both seventeen.
We were two best friends in a small town of barely a five thousand, and, like all other small towns in America, there was never anything to do. We spent out time as most teenagers did; hacking into the school records and spending time trolling online message boards. What? there was nothing to do. We had to find some way to amuse ourselves.
Anthony came over every other day, plugging his phone into my other monitor, and we spent many an afternoon there, side by side, running infomining scripts to write our homework while we duelled each other in the latest deathmatch game mode, or raided together in the older MMOs.
And we talked. Girls, games, hardware specs. The latest advancements in computing; the first quantum supercluster opening in Waterloo I remember quite clearly, discussing the impact on the ageing crypto used by governments across the world. We spent an afternoon trying to crack their servers, to no avail. The future, university, philosophy, space colonization, the singularity. Well, he talked. I mostly listened.
Until the day he lugged it in in a backpack.
"What the hell is that?" I asked, as he dropped it with a thud on the floor.
"This," he says, with a grand sweeping gesture, "is the end of death."
I unzip the bag and pull it down, revealing a matte grey cube, almost two feet on each side. The front had a row of indicator LEDs at the bottom, and the opposite face was dominated by a single circular port, circles within circles, like the cybernetic prosthetic interfaces.
"What did you do?" I ask, "steal a undersea cable box?"
"No. It's crystalline storage."
I finally recognize it. "A yottabyte of storage? That has to be at least ten, fifteen grand. How in Turing's name did you manage to afford that? And what the hell are you going to do with a yottabyte of storage?"
Anthony smiled. "I placed an order for the school, and snitched it when it arrived. They're not going to notice until the end of the year, and they'll just think that it's lost like every other thing they try to find. Besides, it's insured. Probably."
"You're going to get in a lot of trouble."
"And it's already full."
"With what? Rainbow tables?"
"Let me ask you a question. How many neurons are there in the human brain?"
"Uhh. Ten billion?"
"Close. Eighty-six billion, but let's round that to a hundred. Ten to the eleven. And how many different ways are there to network those neurons?"
My head began to spin. "I have no fucking idea. Wait, it's a graph problem, right? A hundred billion nodes, and each node can connect to any other. So for every pair of nodes, you have two possibilities, so it's...two to the power of a hundred billion choose two?"
"Yup. About two to the two-hundred ten. And that's what's stored on there."
"You've lost me."
"Well it's not that simple; neurons are directed, which makes it four to the two ten, but I've culled all the isomorphic graphs and those below a lower bound, and put it some constraints; for instance, the input/output nodes must be connected. I've compressed the rest of the data and it barely fits, but it's all there."
"All of what?"
"The brains of every single human being, past, present or future, imagined or real."
I fell back into my chair and stared at the box. "Jesus Christ."
"No hormones or support cells, but I think the graph is sufficient to recapture consciousness. Of course, each node has to simulate a neuron, and we're still waiting on the biologists for that, but the connections are what make us human."
"I'm in that box?"
"You, me, every possible version of us at any point in our lives. You from the future's in there. You from every possible and impossible future is in there, too."
"But just barely. Just the graph." The shock was beginning to wear off, and I was beginning to see clearly again. It's just a box with a bunch of math in it. "There's nothing in there but blueprints, sketches."
"That's all that matters, don't you see? When anyone dies, nothing is lost; their connections are still stored here! We just need to find them to bring them back. I've reduced immortality down to a search problem!"
"And how exactly do you propose that? Wade down into the sea of lost souls, no, sea of all possible souls, and interview them one by one? Excuse me, are you the late Anthony Weever?"
"Well you could do that—"
"Turing." I rolled my eyes.
"—but you could run it on a quantum computing cluster, and by Grover's Algorithm you cut down it down to two to the hundred evaluations. Which isn't all that bad; brute-forcing a 256-bit key takes about the same amount."
"But you don't have to simulate an entire brain to evaluate a key."
Anthony shrugged. "The search space can definitely be reduced, but you have to admit, it's possible. And if it's possible, we're all still immortal."
"Do you even have a name for it?" I kicked the box.
"I call it the Braintrust. It's a trust for brains."
"Hah hah. Very funny." I rolled back to my computer and whipped up a five second logo, a brain from the top down view, and sent it over to the CNC to mill into a scrap piece of acrylic.
"Also, asking by name won't work. Every version of you is in there, along with every other person ever to share your name. You need to ask for name, date, and a personal identifier, and even that'll only reduce it to a set of all possible yous on that given day..."
I grabbed a can of black spray paint on my desk and rolled over to take the stencil out of the mill. "Not another password. You've already given me at least five to memorize. What's the chance I'll ever need to use the password from my future self?"
"Never hurts to be prepared. But in this case, the longer the better; thirty-six bits should be sufficient."
I sprayed the stencil onto the top of the box, and when I removed it, the brain still shone with the wet paint.
Anthony never did get in trouble, but the school upgraded their crypto the year after, and neither of us tried again. We settled on a series of four questions to sieve our souls from the sea, to separate our real mind from the set of all possible minds. And we memorized yet another password, this one written to disk in encrypted form.
Talk about the Braintrust drifted on for about week, then faded away like everything else we talked about, like every other godawful foolish plan we dreamt up in our youth.
He never brought the Braintrust back over, and, within a month, we both forgot.
We drifted apart after high school, as friends usually do, going to universities on opposite ends of the state. We kept somewhat in touch, meeting up on occasion when we were both in town, but neither of us ever wanted to go back, caught up in the whirlwind of the big city. Anthony majored in comp sci, myself engineering, and once we got our degrees we barely saw each other again. He went to my wedding (he never had one himself) where we resolved to see each other more often.
The next time I saw him was at his funeral, a year later.
Not even him. A fire had gutted his apartment in his sleep; a faulty power supply. He got up, but never made it to the door.
The casket was closed.
It was six months later when the Braintrust arrived, wrapped in brown paper and string, and attached with a note from his mother. It had been sitting in the attic for almost half a decade, untouched, but was specifically to be given to me in his will. I unwrapped the package, and a single sticky note, no longer sticky, sat atop the box, written in Anthony's hand.
The logo was still there, slightly scuffed, drops of paint misted past the stencil.
I couldn't say no.
But before I could access the data stored in the Braintrust, I had to find a cable. The net said that it was an obsolete standard for older computing clusters, designed for massively parallel access to the crystalline data array. I ordered a parallel-to-USB converter off eBay, and when it arrived I plugged it into my glass and powered it on. A green light flickered on at the bottom of the cube, and filled my view with data.
I opened the README first.
If you are reading this, I am most likely dead.
You never really did believe in this endeavor, and within good reason, too. Neuron simulations were finished in the 2039, and even now, and probably by the time you read this, they still won't be simulating human-level intelligences. They're still trying to map the brain, to simulate it, looking to start from smaller animals, cats, dogs, primates.
Sometimes you just need a brute force approach.
I've done it, Dor, by Turing I've done it. I've found a copy of myself, who thinks and acts exactly as I. He's in here, along with everything you need to find someone. It just takes resources.
I've shrunk the sea a bit; cutting out anything that can't pass the Turing-Griffin test. It's more of a river rather than an ocean now, easier to traverse, though it wasn't cheap. But it'll make further searches exponentially easier.
And I'm now lost up that river, and I'm asking you to find me. I know you owe me nothing; I haven't been the best of friends, I've never been good at keeping in touch. But I'm asking you a favor, to find me in this crystalline underworld, to sieve me out from the quntillion souls that are frozen with me and bring me back to the world of the living.
One last thing. My last request. Don't even think of saying no.
I take off my glass and rub my eyes, before diving back in.
Two more files resided in the root directory: Anthony's private key and his password, encrypted, made that afternoon almost twenty years before. Both the key and password fed into the program, a check for each of the souls, meant to be known to no man but its maker. I kept it encrypted, untempted.
I dove into the directory structure next, swimming through the glowing form. The river branched early, snaking off to the programming side of things: the simulation code for the neurons, the parsing of neuronal impulses through simulated vocal folds, feeding the audio into a natural language processor. Responses were then compared to the correct answers, which fed back the script that governed the load distribution between the accessible clusters.
Which left the second branch, the database.
The main trunk was straight and broad, with few rivulets branching off for the main flow; the human brain was similar in basic structure, with little room for variance. But further downstream the trunk forks and spreads, as individuality asserts itself.
A single rivulet glowed red, traced from the root, annotated by Anthony five years prior. It lead to a single graph, labelled with a date, and a cryptic note.
Don't forget to drop in.
I rented computation time from the Waterloo cluster, and went in person; the sheer volume of data from the Braintrust couldn't be transmitted through the internet. Their cluster had a matching jack, and I was ushered into a small conference room where I plugged the Braintrust in, and began running the simulation.
Starting with the red graph.
"Hello?" I spoke into the empty room.
"Hey. Dorian, is that you?" the voice in my headphones. The voice was flat, generic. "I'm dead, aren't I?"
"Who is this?"
"Anthony Weever, February 2041, last instantiated April 2041. What year is it now?"
The wheels in my mind spun uselessly. "2047. January. You died last May. Apartment fire."
"A shame. Well, I'm still here. So, how's the past six years been? Miss anything important?"
"My wedding. First permanent lunar base. Korean reunification. Not much on the tech side, unfortunately. Still nowhere near human-level AI. Brain mapping still on idle."
"As expected. Congratulations, by the way."
"Thanks. Wait, how do I know that you're Anthony?"
"Well, I'm assuming that the real Anthony told you to run this graph first, but how do I know I'm real? I don't. I answered the questions, talked with the real Anthony, and apparently that was good enough for him."
"Then how do you still remember?"
"Oh, I'm not an exact copy; the graph changes as I'm simulated. Anthony saved a copy at the end of the simulation, as well as the state of the neurons. I've also been instructed to answer any other questions you may have. I am the documentation, so to speak."
"How long did it take to find you?"
"Running the Turing-Griffith test on all graphs took about two years and a couple million dollars, but that's all done now. He added another password to find the closest copy of himself, which took about a week, but he kept a list of all the copies of himself, so you can sort through those first."
"Why don't you just take his place? You're a sufficient backup, there's no reason to search for the most recent backup. You can just take is place."
"I've asked that question myself. It's about continuity. Not for me, but for the rest of the world. How far back can constitute a sufficient backup? Do we claim that the experiences of the intervening years are invalid? Only one copy can be active at any point, otherwise the rights of everyone in the Braintrust is called into question. Is it right to simulate minds for a few minutes for testing, before shutting them down and consigning them to indefinite slumber? Only if we declare a single canon copy can we reject their right to existence, and only wake them in search of the real copy."
"So you don't have any rights?"
"No right to existence, but as a sentient being, rights against torture and other such things. I would find it morally objectionable to you torturing me, or any graph, but not if you shut me down, or refuse to instantiate one."
"Why didn't you make it public? You are proof that the Braintrust works, an offer of immortality for everyone."
"Does it matter if people are immortal now or later? The processing power for simulation is still out of reach for most individuals, and I release it now, only the rich will benefit, and it'll be kept out of reach of the population forever. Or I can wait until immortality is in the reach of all. Any other questions?"
"Right then. Here's how you start the search."
Anthony shut himself off when the search began; no sense wasting extra cycles. I booked a hotel room and stayed as the cluster continued its search. Name, date of birth, current date, password. Over and over again.
It took two days before the cluster reported a hit. I returned to the cluster, and resumed up the simulation, paused upon hearing the correct answers.
"Hey Dor. Nice talking to you again. I'm dead, aren't I? No other reason for the sudden blindness and the four questions."
"What's the last thing you remember?"
"Going to get coffee. I was at work. How'd I die?"
"Apartment fire. Tomorrow morning. Well, relative for you. It's January now."
"Missed an entire year. How's Liz?"
"Pregnant. She's due in July."
"Yeah. So, are you sufficiently close to your death to count as canon?"
"Sorry? Oh, you talked with the documentation. Well really, it's up to you."
"Well, I might of thought that way five years ago, but really, the mental gymnastics are impossible. The Braintrust holds the continuity of consciousness, the continuity of all consciousnesses, and you're trying to split a continuous process into discrete components, individuals that can be defined as different. That's why there's a human component, to judge whether or not the graph deserves continued existence. Because processing power is limited, and we should designate that towards those who have already existed, rather than those that might.
"So tell me, am I canon?"
"As far as I can tell. Welcome back to the land of the living."
"Thanks. I'll keep in touch."
And with that he was gone.
He had access to the internet, and later analysis would show that he uploaded himself online, onto a distributed botnet. He must have set that up while he was still alive.
I don't know what he's doing, but things are moving quickly now; they're sending a crew of general-purpose AI to Mars, and Moore's Law is back on track. I don't know how much Anthony has to do with it.
I haven't seen him since.