What the Arm Knows

The keeper, whose name was Priya, had told them twice not to put their hands in the tank, and then had walked off to argue with somebody about a broken pump. So Maya and Soren stood alone with the octopus.

It was small, no bigger than a grapefruit with the arms folded in, sitting in a plastic transport tub of seawater on the counter. One arm had crept up over the rim and was moving along the outside of the tub, curling and uncurling, the little suckers opening and shutting like it was reading braille off the plastic.

"It's looking for a way out," Soren said.

"It's not looking," Maya said. "It's not even pointing its eyes that way."

She was right. The octopus had one eye, a strange horizontal pupil, aimed straight at the two of them. The arm was doing its own thing entirely, off exploring, like it hadn't been told the eyes were busy.

Soren leaned in. He had put a paperclip on the counter earlier, and a bottle cap, and a scrap of shrimp Priya had left in a dish. The arm reached the paperclip. Touched it. Moved on. Reached the shrimp scrap. Stopped.

"Watch," Soren said. "It skips the metal."

"Do it again."

He slid the paperclip back into the arm's path and put the shrimp beside it. The arm came out, brushed across both, and folded around the shrimp. It ignored the paperclip completely. Same shape, roughly. Same size, roughly.

"How does it know," Maya said. It wasn't quite a question. She was already staring at the suckers.

"Its eye isn't on the shrimp," said Soren. "So it's not seeing it."

"It's not seeing anything. The arm's around the far side of the tub." Maya put her chin on the counter, level with the water. "The arm found the shrimp with the arm."

They were quiet. Down the corridor, Priya was saying something about impellers.

"Feel it, maybe," Soren said. "Shrimp is soft. Paperclip is hard."

"Then give it two soft things."

Soren looked in the shrimp dish. There was a slice of raw potato in there too, from somebody's lunch, going a little grey at the edges. He cut it with his thumbnail until it was about the size and squish of the shrimp scrap. He set them both down, potato and shrimp, side by side, and nudged the tub so the arm's roaming brought it across the pair.

The arm swept over both. Same softness. Same size. It curled around the shrimp and left the potato sitting there.

"Okay," Soren said slowly. "That's not feeling. That's not shape. It touched both the exact same way."

Maya sat up. "Touching is the same as tasting."

"What?"

"For it. The suckers. It's not feeling the shrimp to find out it's shrimp. It's tasting the shrimp. With its arm. The touch and the taste are the same thing." She said it fast, running past herself, then slowed to check her own work. "That's why the eye can look at us. It doesn't need the eye. The arm already knows what it's holding, because holding it and tasting it are one thing."

Soren reached for the notebook in his back pocket. His hand found the pencil, opened to a clean page, and drew a single sucker, a small ring, with a question mark inside it.

"Test it," he said. "Something that tastes like shrimp but isn't shaped like shrimp."

Maya was already dipping the potato into the shrimp dish, rolling it in the little smear of juice and shrimp bits. She set the shrimp-flavored potato in the path and pulled the plain potato back.

This time the arm brushed the potato, and instead of moving on, it stopped. The suckers spread over it. It gathered the potato in, the wrong shape, the wrong squish, the wrong everything, and drew it toward the underside where the mouth hides.

Then it stopped. Held the potato a moment. And pushed it back out, unhurried, the way you'd put down a book that turned out to be the wrong one.

"It grabbed it," Soren whispered. "It grabbed it because it tasted right. Then it kept tasting and figured out the rest was wrong."

"The whole arm is a tongue," Maya said.

She was looking at all the suckers now, not just the one at the tip. Rows of them, down the entire length of the arm, and it had eight arms, and each sucker was its own small mouth that never ate, just tasted, all of them tasting at once, hundreds of them, thousands across the whole animal.

"Soren." She grabbed his sleeve. "When it reaches into a crack in a reef, in the dark, where its eyes can't go."

"It's tasting the inside of the crack."

"The whole inside. Everywhere the arm touches. All at once. It knows if a crab is hiding in there by what the rock tastes like next to it." Maya's voice had gone up. "It doesn't have to look. It doesn't have to pull anything out to check. It's licking the entire cave the second it walks in."

Soren wrote it down, the words coming out crooked because he wasn't looking at the page, he was looking at the arm still moving along the rim, tasting the plastic, tasting the water, tasting the place where the water met the air.

"Imagine that," he said. "Imagine if your fingers tasted everything they touched. You'd know your whole desk without seeing it. You'd taste a door before you opened it."

"You'd never be bored," Maya said. "Everything you touched would be information. You couldn't turn it off."

They looked at each other, and it was the same look, the one that meant they had both landed somewhere new and were standing on it together.

Priya came back around the corner, wiping her hands. "Alright, you two, I told you, hands out of the tub."

"We didn't," Soren said. It was true. Their hands had stayed on the counter the whole time.

Priya lifted the octopus tub to carry it to the tank. The arm that had been exploring the rim reached out as the tub swung, and its suckers pressed for a second against the back of her hand, then let go.

"It does that," Priya said, not really noticing, moving on down the corridor. "Grabby little thing."

Maya watched her go, watched the arm still tasting the air, and said quietly, to Soren, to nobody, "It just found out what she had for lunch."

The octopus turned one horizontal pupil toward the two children as the tub floated past, while its arm went on reading the whole world it was passing through, one sucker at a time.