When Apple announced the iPhone 4S on October 4, 2011, the headlines were not about its speedy A5 chip or improved camera. Instead they focused on an unusual new feature: an intelligent assistant, dubbed Siri. At first Siri, endowed with a female voice, seemed almost human in the way she understood what you said to her and responded, an advance in artificial intelligence that seemed to place us on a fast track to the Singularity. She was brilliant at fulfilling certain requests, like “Can you set the alarm for 6:30?” or “Call Diane’s mobile phone.” And she had a personality: If you asked her if there was a God, she would demur with deft wisdom. “My policy is the separation of spirit and silicon,” she’d say. Over the next few months, however, Siri’s limitations became apparent. Ask her to book a plane trip and she would point to travel websites—but she wouldn’t give flight options, let alone secure you a seat.