India, Nov. 24 -- Recently, while ordering dinner from the same neighbourhood restaurant I have trusted for years, I noticed something unsettling. The price of my usual dish had risen by nearly twelve rupees. There had been no shortage of ingredients, no sudden rise in wholesale costs, no inflationary jolt worth mentioning. The reason lay elsewhere. At exactly 7:42 pm, an algorithm had calculated that demand in my pin code was likely to rise. When I mentioned this to the restaurant owner the next day, he smiled faintly.

"It's not my rate," he said. "The system decides now."Later that evening, my taxi home cost almost double what I had paid that morning. The weather was calm. Traffic flowed smoothly. Nothing in the physical city had changed...