1. Plan for the long term
Once, the ruin was a city called Toronto, and its buildings spread horizon to horizon, a safe habitat for people like Jeydah.
Now it is only the ruin: a maze of collapsed masonry and broken machines. Jeydah visits once a month to gather salvage and pick berries from the sprawling brambles that grow in its once-proud avenues. The people in the plains villages think her strange, but they barter with her all the same, and she stays fed on the tools that she finds, the gadgets she makes.
The best salvage, though, Jeydah keeps for herself: a sphere that gives off light; a pane of glass you can heat with a touch; a small black block that speaks stories of the way the world once was. She keeps these treasures in a weatherproof sack, safely hidden in a hollow tree half-a-day’s walk from the ruin.
Or perhaps not so safely, because when she stops at her tree one chill autumn day, the sack is missing, her treasures gone. The breaks in the long stalks of grass nearby look recent, so Jeydah hikes on without stopping. No matter how badly she wants her things back, few people in the wastes are kind to strangers.
It’s dark when she reaches the ruin, and for the first time in all her visits, she notices something new. Light — pale and steady as her stolen sphere’s — pooled inside a narrow arch at the ruin’s outermost edge.
2. Eliminate barriers to access
The arch leads to a stairwell, which leads to a warren of tunnels. As Jeydah walks, arrows light the floor, pointing her down a path she would never have found without them.
At any other time, she would have marvelled at this ancient tech, but tonight her shoulders ache with tension. Although she has not encountered whoever stole her things, she saw dust rising from the dry road behind her as she fled her tree. She jogs through the tunnels as fast as she dares, hoping her pursuer is more timid than she is.
After countless twists and turns, the arrows dead-end against a wall — solid, smooth and indistinguishable from any other in this place. Jeydah spins around, throat tight, but only manages three steps before the tunnels plunge into darkness.
At least she knows she wasn’t followed.
She laughs once, bleakly, then feels her way back to the dead end and leans against it, head bent, eyes closed. When the wall dissolves, she falls right through.
3. Break down complex tasks
The room behind the wall is large and open, suffused with a pale blue glow that leaves many of its features in shadow. More arrows lead Jeydah to the far wall, which whirrs open to reveal a bowl. The smell of chillies and roasted grain meets her nose, and her stomach growls.
She should be cautious, but she’s tired and hasn’t eaten in nearly a day. Besides, she’d be dead already if whoever built this place wanted it. She lifts the bowl from its platform.
The arrows change, leading her to a chair lurking in the shadows. The instant she sits, the wall flickers to life with staticky symbols. She can’t read them, of course, but there’s a picture of a person in the chair pushing a button and that seems clear enough.
She looks down, finds the button, and pushes it.
The lights in the room increase, and the wall displays more symbols, more pictures: the person in the chair retrieves objects from the wall, puts them together to build tool after tool. The person multiplies until a whole community tills the land, builds structures, rides wagons that move themselves.
Jeydah stares, entranced, until the wall flickers and shows a single picture of the archway, a black panel and a lightning bolt that’s cut in half.
The wall whirs open, revealing a panel. Jeydah picks it up, looks at the picture on the wall, and heads into the labyrinth.
4. Always have a back-up
Jeydah takes a few hesitant steps into the tunnels, relaxing only when she sees the arrows appear beneath her feet, pointing her onwards.
After that, it takes no time at all to reach the stairs and climb to the surface, where the Moon hangs low and full above the ruin. Not much longer to clear the roof behind the arch of the debris that clutters it.
Black panels glimmer in the moonlight, one of which is cracked. She pulls it free and replaces it with the new board, then slips back below the surface.
5. Make past results reproducible
As she follows the arrows back through the tunnel, Jeydah hears hiccupping sobs, high-pitched and desperate, that seem to come from every-where at once.
In all her explorations of the ruin, Jeydah’s never once met a ghost, so she squares her shoulders and follows the sound to a small, hungry-looking girl, hunched over a sack that looks awfully familiar and crying her eyes out. The child looks up as Jeydah approaches, clutches the sack to her bone-thin body, and scurries back against the tunnel wall, chin held up defiantly.
If Jeydah had found the little thief at her clearing, she would have snatched the sack back in an instant. Fought the girl if she had to. Harsh, but the wastes are harsh. The world is.
After the wonders of the labyrinth, though, after the secret room with its hot food and its worlds-ago tech, that seems petty. Unjust. She remembers the pictures on the wall. Remembers how hungry she was as a child.
She squats down next to the girl, relaxes her shoulders, puts on her most disarming grin. “Hey,” she says. “You want something to eat?”
Nature 561, 144 (2018)