The nurse had said it lightly, on her way past. She said Soren's grandmother would be fine once her gut bacteria settled down again, since the antibiotics had knocked them all sideways.
Then she was gone, and Soren was left holding the sentence.
"Bacteria," he said. "Inside her. She has bacteria and they got knocked sideways and that's why she feels bad."
Maya was sitting on the floor with her back against the wall, because the chairs were the kind that made you slide off. "Everybody has them," she said. "You have them. Right now. Billions."
"That's not the same as thinking about it." Soren sat down next to her. He had his notebook but he did not open it yet. "How many, though. Actually."
"A lot."
"That's not a number."
Maya tipped her head back against the wall and thought. "Okay. I read once that they weigh a couple pounds. Like, if you took them all out and put them on a scale."
"A couple pounds of what, though. A couple pounds of you, or a couple pounds of not-you?"
Maya turned her head to look at him. "Say that again."
"Your grandma is in there. And the nurse is worried about the bacteria. Like the bacteria are part of the patient. Like they're on the chart."
"They kind of are on the chart," Maya said slowly. "That's the weird thing. She didn't say the medicine hurt Grandma. She said it hurt the bacteria and that's why Grandma feels bad."
Soren opened the notebook now. He wrote hospital hallway and then he stopped, because he did not know what he was counting.
"Here's what I don't get," Maya said. "If they're just riding along. If they're just, like, guests. Then who cares if the medicine knocks them sideways. You'd feel fine. But she doesn't feel fine."
"So they're doing something."
"They're doing a job." Maya sat forward. "That's why she feels bad. The workers went on strike."
Soren wrote workers. "What job."
"I don't know. Something we can't do ourselves, or we wouldn't need them." She frowned. "There's stuff in food you can't unlock on your own. Like, your own body doesn't have the tools. Fiber, I think. Certain vitamins. The bacteria have the tools and they hand the stuff back to you."
"How do they have tools we don't."
"Genes," Maya said. "Tools are genes. A gene is a recipe for a tool."
Soren stopped writing. "Wait. How many genes do we have. Us. Humans."
"Like twenty thousand? Something-thousand."
"And them?"
Maya didn't answer right away. She was doing the thing where she chased a shape before she had the words for it. "More," she said finally. "Has to be more. Because there's a ton of different kinds of them, and each kind brought its own recipes. You've got one human genome. But you're carrying, like, thousands of different bacteria and each one has its own book."
"How much more, though. Ballpark."
"I'm not going to guess low," Maya said. "I always guess low and I'm always wrong that direction." She held her hands apart, the way you do when you cannot say a number so you show it instead. "Way more. Like it's not even close. Like your own recipes are a shelf and theirs are a library."
Soren wrote a shelf and a library and looked at it.
"Okay but back up," he said. "You said a couple pounds. That sounds small. A couple pounds is nothing. That's a bag of sugar."
"Pounds is the wrong way to count them," Maya said. "They're tiny. Each one is way smaller than one of your cells. So a couple pounds of something that tiny is a huge number of things."
"Huger than us?"
"Us how?"
"Cells," Soren said. "How many cells are you. The actual you. Skin, blood, brain, all of it."
Maya went quiet. "Trillions."
"And them. If they're tinier and they weigh two pounds anyway."
"Trillions," Maya said again, and her voice did something on the word.
They looked at each other in the hallway.
"So it's a tie," Soren said. "Roughly. Roughly a tie. However many cells are you, about that many cells are them." He wrote it very carefully. Half. He crossed it out. He wrote a tie.
"That can't be right," Maya said, but she was smiling the way she smiled when a thing was too big to be anything but right. "I would have noticed. You'd think you'd notice being half something else."
"You wouldn't, though." Soren was talking fast now. "That's the whole thing. You'd never notice, because they're doing the quiet jobs. The unlocking. The vitamins. All the stuff you can't do with just your own shelf of recipes. They've got the library. And you never see the library because it's inside you being helpful."
"Until the medicine knocks it sideways," Maya said, "and the jobs stop, and Grandma feels it."
They both looked at the closed door.
"She's in there feeling it," Soren said quietly. "The strike."
"She's not just a person feeling sick," Maya said. "She's a whole population. Half of her is waiting to come back to work."
Soren looked down at his own hands. He turned them over. He looked at the backs of them, and then the palms, like there might be something to see, which there wasn't, and he knew there wasn't, and he kept looking anyway.
"Every number I know about myself is wrong," he said. "I've been counting one person this whole time."
Maya held her hand up next to his, palm out, not touching, just measuring the two of them against the hallway light.
"Nobody in this whole building is one person," she said. "Not the nurse. Not the doctors. Not anybody walking around out there thinking they came in alone."
The door opened, and Soren's grandmother's voice said his name, and the two of them scrambled up off the floor, four hands, two children, and everyone else neither of them could see.
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A science-verified short story for curious kids · Curiosity Land