Lopsy

A crowd of young animals gathered around, trying to decide which rule was better. They were getting lost. There were so many results. Some of them started adding up totals, some started drawing charts, and everyone was talking at once.

Lopsy hopped up onto the table, flopped ear swinging. "Wait," she said. "Most of these pairs don't matter."

Everyone stopped. "What do you mean, they don't matter?"

Lopsy picked up the first pair. Both rules had won that deal. "Look. This deal was easy. Both rules won it. So does it tell us which rule is better?"

The crowd thought. "No," said a mouse slowly. "They both won. It's a tie."

"Right," said Lopsy, and set the pair on the big pile. She picked up another. Both rules had lost. "This deal was impossible. Both rules lost. Does it tell us anything?"

"No. Another tie."

On to the big pile it went. Lopsy worked quickly now, paws flying. Both won, big pile. Both lost, big pile. Both won, big pile. The big pile grew and grew. Every pair where the rules agreed went there, because a pair that agrees can't show a difference.

Then she found one where the take-back rule had won and the no-take-back rule had lost. She set it apart, carefully, on the small pile. A few more pairs later, she found another like it. And then one the other way around, where only the no-take-back rule won.

When she was finished, almost all forty pairs sat in the big pile. Only five sat in the small one: four where just the take-back rule won, one where just the other rule won.

"There," said Lopsy, and her upright ear quivered with delight. "These are the whole story. On thirty-five deals the rules did exactly the same thing. The only deals where the rule made a difference are these five. And four of them went one way."

The crowd leaned in. Suddenly the answer was simple and clear, when a minute ago it had been a jumble. Taking a card back helped, but only on a few deals, because most of the time it didn't matter at all.