The Machine That Beat Us at Our Own Rules

The rule list was three pages long, and Soren had written every line of it.

"A bird has two wings," he read. "A bird has a triangle beak. A bird has a round body. A bird has a tail that points."

"Read the next one," said Maya.

"A bird's eye is a dot inside the head, not outside."

They were teaching a little program to look at drawings and say bird or not bird. The contest gave you five hundred drawings that other kids had made, and your program had to sort them. Soren had spent two weeks writing rules. Maya had spent two weeks watching him and frowning.

"Run it," she said.

Soren ran it. The program looked at the practice drawings and started guessing. Bird. Bird. Not bird. It got the neat ones right, the ones that looked like the birds in a coloring book. Then it hit a drawing some kid had made of a fat pigeon with no visible beak and a scribble for a tail.

"Not bird," said the program.

"That's a bird," said Maya.

"The beak rule failed," said Soren. He was already writing. A bird may have a hidden beak. He added it to the list. Now the list was three pages and one line.

They ran it again. It fixed the pigeon and broke on an ostrich, which had a long neck and no wings anybody bothered to draw.

"A bird may have a long neck," said Soren, writing.

"How long is your list going to get," said Maya. It was not really a question.

"As long as it needs to be."

Maya pulled her chair over. "Every kid drew a bird a different way. There's a kid who drew a bird as a letter M with a dot. There's a kid who drew every single feather. Your list is trying to be right about all of them at once."

"That's the whole point of the list."

"The list is you," she said. "It's you deciding what a bird is. But you're not the one who drew these."

Soren stopped writing. That landed somewhere he couldn't argue with right away.

There was another way to do the contest. The club advisor, Mr. Okafor, had shown them at the start and then wandered off to fix the 3D printer, which he loved more than any of them. The other way did not use rules at all. You gave the program thousands of drawings that were already labeled bird or not bird, and you let it look at them, and it found its own way of telling them apart. Nobody wrote it down. Nobody could even read what it found.

"I didn't want to use the second way," Soren admitted, "because I couldn't see inside it. With my rules I know exactly why it says bird. The other way is just a box that gets it right and won't tell you how."

"So it bugs you because you can't check its work."

"It bugs me because it works and I don't know why."

Maya grinned at him, delighted. "Let's race them."

They set it up. Soren's rule program, three pages and now four, on one side. The other kind on the other side, fed a big pile of practice drawings, thousands of them, dumped in from the contest's open folder. It chewed through them for a few minutes while its numbers slid around. Then they gave both programs the same two hundred fresh drawings, ones neither had ever seen.

Soren's rules got a hundred and forty right.

The other one got a hundred and eighty-six.

"Run it again," said Soren.

They ran it again with fresh drawings. Same gap. His careful list, every line of it a true thing about birds, lost to a box that had never been told a single true thing about birds. It had only been shown them.

"Add more data," Maya said quietly. "To the box. Give it more."

They dumped the whole practice folder in, every drawing the contest had. The box's score climbed to a hundred and ninety-one. Soren added three more rules to his list. His score climbed to a hundred and forty-two and stuck there like a wheel in mud.

"It's not fair," said Soren, and then heard himself. "No. It is fair. That's what's strange."

"Your rules are everything you know about birds," said Maya. "That's the ceiling. It can't get smarter than you."

"And the box has no ceiling," Soren said slowly. "It just needs more drawings."

They sat with that. Outside the room the 3D printer whined through a layer. Soren looked at his four pages, every line correct, every line something a person would nod at. A bird has two wings. True. And useless next to the thing that had never heard the word wing.

"Here's what gets me," said Maya. She had her knees pulled up on the chair now. "Nobody wrote the box's rules. So they're in there somewhere, right? It found rules. Better ones than yours. And no human being has ever read them."

"They might not look like rules at all," said Soren. "They might be nothing we'd recognize."

"There's a right way to tell a pigeon from a paper airplane," Maya said, "sitting inside that box right now, and it's better than anything a person figured out, and it's invisible."

Soren reached for his notebook. His hand stopped over the page. He looked at his three-page rule list instead, the one he had been so proud of, and he did something he had not planned. He picked it up and set it face down on the desk.

"What are you doing," said Maya.

"Feeding it the last folder," said Soren. "All of it. Everything we have."

He dragged the whole pile of drawings into the box and let go. The number counter started climbing again, ticking up as it looked at thousands of birds it had never met, teaching itself something neither of them would ever be able to read.

Maya leaned toward the screen. The count kept rising.

"Give it more," she said.