It was nine o’clock on a Friday morning when they decided to launch. Prometheus was humming away in its custom-built computer cluster, which resided in long rows of racks in a vast, access-controlled, air-conditioned room. For security reasons, it was completely disconnected from the internet, but it contained a local copy of much of the web (Wikipedia, the Library of Congress,Twitter, a selection from YouTube, much of Facebook, etc.) to use as its training data to learn from. * They’d picked this start time to work undisturbed: their families and friends thought they were on a weekend corporate retreat. The kitchenette was loaded with microwaveable food and energy drinks, and they were ready to roll.