Before their first camping trip, Will made a checklist with forty-seven items. He packed a torch, spare batteries, waterproof matches, an emergency whistle and two kinds of insect repellent.
At the campsite, he laid everything out in careful rows. His wife looked at the pile, then at the empty patch of grass.
“Where’s the tent?” she asked.
Will scanned his list. The last line said CHECK THAT NOTHING IS MISSING.
He ticked it proudly.
“You can’t tick that,” she said. “The tent is missing.”
“Then the checklist worked,” Will replied. “I found out before bedtime.”