“How much of this is knowledge—and how much is just a very convincing guess?”… In the summer of 2026, Kenji had become accustomed to asking his AI assistant questions before asking anyone else. The assistant lived in his smartphone, listened continuously for commands, and had access to a web of public databases, business directories, government filings, archived websites, customer reviews, and real-time search results. It could summarize a hundred pages faster than Kenji could read a paragraph. Most days, it seemed nearly omniscient. One afternoon, however, a simple phone call exposed a weakness that thousands of engineers had spent years trying to eliminate. The call arrived from an unfamiliar number. Kenji ignored it. A few minutes later he asked his AI: “Who owns this number?” The assistant responded confidently. “It belongs to the customer support center of a rental service you use.” The answer sounded plausible. He was indeed a customer of a vehicle-s...