The parable of the doors

"Identical clinics had opened worldwide following the parasite's discovery - a biological oddity colloquially dubbed 'the Slug', despite news broadcasts highlighting the microscopic creature's dendritic shape. How they'd spotted the Slug, Balch couldn't explain. But he understood why it mattered. Apparently, the Slug had been randomly infecting half the population for centuries. It wasn't deadly, supposedly. Yet it dulled its host's every faculty, hampering their ability to do most things - including reasoning cogently, retaining information and even playing sports. How the Slug spread, the World Health Organization couldn't say. Yet that hadn't prevented scientists from developing a cure packaged in bubblegum-flavoured oral lozenges."

""Boring wait, huh?" Balch turned. Behind him stood a youngish, bespectacled man in a tweed suit and bow tie meant for someone four times older. "If you need entertaining," he said, "how about a riddle?" "Why not," said Balch. "Picture a game show," said the man, "involving three doors. One conceals a million dollars. The others, nothing. You'll win whatever's behind the door you choose. With me so far?" "Yup," said Balch. "Guess correctly, make a bundle.""

Balch waits in a long, orderly queue outside a clinic established to detect and cure a pervasive parasite known as the Slug. The Slug infects roughly half the population, dulling cognition, memory, athletic ability and reasoning while remaining supposedly nonlethal. Governments implemented mass screenings and nurses and guards process people for dosing with a bubblegum-flavoured oral lozenge cure. The World Health Organization cannot explain transmission. Balch feels anxious and uncertain whether he carries the parasite, and a bespectacled man in the queue tries to pass time by posing a three-door riddle.

Read at Nature