You have heard that the human attention span has fallen below a goldfish's. It is one of the most quoted statistics of the digital age, repeated in TED talks and tenth-grade classrooms, in newspaper trend pieces and the pitch decks of companies selling a cure for the affliction they just named. The claim has a single defect its champions rarely raise. There was never a study. There was never a goldfish. The number was invented, and a century took it as a verdict on itself.

The Eighteen-Minute Lie is the biography of that lie. David Boles tracks a fabricated figure from its murky origin to its grip on the culture, and asks the question its sellers were careful never to ask: who gets rich when a civilization is persuaded it has lost its mind? The trail runs through the survey mills that manufacture certainty by the pound, through the attention merchants who auction a single human glance in the time it takes to blink, and through a long line of people who actually studied how the mind attends, from William James to Herbert Simon to Gloria Mark, who found nothing resembling the collapse being sold in their names.

What surfaces is a portrait of how a useful falsehood outruns the truth, why a frightened public buys the diagnosis along with the remedy, and how the panic over attention became one of the most profitable products of the modern age.

A reckoning with a lie, and with the appetite that made the lie easy to swallow, this book is also a case for taking your attention back from the people who grow rich insisting you have none left to reclaim.