The rain came down so hard it turned the museum windows into gray water, and Maya had already seen everything twice. Her mom was reading the panel on sleep for the third time. So Maya wandered to the table in the back, the one nobody stood at, where a rubber hand lay on a black cloth with its palm up like it was waiting for change.
A card said: PUT YOUR HAND IN THE BOX. So she did.
Her real right hand went into an open-sided box, out of sight. The rubber hand sat on the table in front of her, where her hand should have been. A bored museum guide named Devin sat on a stool nearby, tapping his phone.
"You brush both," Devin said without looking up. "Same time. It's a trick. Takes a minute."
He reached over with two small paintbrushes. One brushed the fingers of the rubber hand. The other, inside the box, brushed her hidden real fingers. Same stroke. Same speed.
At first it was just cool bristles on skin she couldn't see, and cool bristles on rubber she could. Two separate things.
Maya kept her eyes on the rubber hand.
Stroke. Stroke. The brush slid down the rubber pinkie, and inside the box the brush slid down her pinkie, and something in her stomach went strange, the way an elevator makes your insides lag behind you.
Stroke across the knuckles. Stroke across her real knuckles, hidden. She watched the paintbrush touch rubber and she felt the touch. Not near the rubber. In it. The feeling had crawled out of the box and climbed into the fake hand on the table.
"That's weird," Maya said. Her voice came out quieter than she meant.
"Told you," said Devin, still tapping.
She wanted to test it. She always wanted to test it. She asked him to stop the brushes and just tap once, on the rubber thumb only, nothing in the box.
Devin sighed and tapped the rubber thumb. Nothing. Just a tap on a fake thumb, dumb and dead.
"Now both again," she said.
Brush and brush, together, together, together, and the rubber warmed into hers again. It was the sameness that did it. When the two touches matched, the hand became her hand. When they didn't, it went back to being a prop.
Maya breathed slow. The rubber fingers were her fingers now. She could almost feel the table under them, cool and flat, though she knew, she absolutely knew, her real fingers were in a box touching nothing but air and a paintbrush.
"Okay," she said. "Do the last part. The card says there's a last part."
Devin looked up for the first time. "Some kids don't like the last part."
"I want it."
He kept the brushing going with one hand. With the other he picked up a little rubber mallet, the toy kind, and without warning he brought it down on the back of the rubber hand.
Maya yanked her real hand out of the box.
She pulled it back before her brain had time to ask her to. It was already halfway to her chest, fingers curled, and her heart was going like she'd touched a hot stove. Nothing had touched her. Nothing at all had touched her real hand. A foam mallet had bopped a piece of rubber on a table.
And her body had flinched to save a hand that was not hers.
"Whoa," said Devin, actually setting the phone down now.
Maya sat there holding her real hand, the one that was fine, the one that had never been in danger, and she felt her pulse in her fingertips. She looked at the rubber hand lying there on the black cloth, harmless, and then at her own hand, safe against her shirt, and she couldn't fully believe that the safe one was the real one. Part of her was still braced for pain that had aimed itself at a thing made in a factory.
She put her hand back in the box.
"You want to go again?" Devin said, like she was strange.
"I want to know how it decided," Maya said.
"Decided what?"
"Which hand was me." She wasn't really asking him. She was watching the paintbrush. "Nobody told it. My eyes said the rubber one. My skin said the box. They both can't be my hand." Stroke, stroke. "So something in there picked. It just took the touches that lined up and built a hand out of them."
Devin nodded slowly, like this had never occurred to him in a whole day of doing it.
Maya thought about her own actual hand, the one that had held a pencil that morning, that had felt the rain-cold window, that she had never once doubted was hers. She had never doubted it because the touches always lined up. Her whole life, every second, the touch and the sight and the feeling from inside had all matched, so smoothly she never noticed a decision was being made. But it was being made. Right now. All the time. Something behind her eyes was quietly voting on which pieces of the world counted as her, and mostly it voted yes on her arms and legs and no on everything else, and it had just been fooled into voting yes on a rubber hand from a paintbrush and a plan.
Which meant the edge of her, the exact line where Maya stopped and the room started, was not a fact.
It was a guess her brain was making. A good guess, updated constantly, usually right. But a guess.
She held very still and looked at the rubber hand, then at the box she couldn't see into, then at the rain making the whole window run like it wasn't glass anymore.
"Do it again," she said, and put both hands flat, one seen, one hidden, and waited for the brushes to start deciding where she was.
Out in the box, in the dark, the bristles touched her fingers, and on the table the rubber fingers felt it too.
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A science-verified short story for curious kids · Curiosity Land