A few years ago, my dad came to visit me while I was living in France. On a night out, we went to the arthouse theater in Montpellier to watch a Chinese movie that had just come out. The movie takes place in Shanxi province, a few hundred kilometers west of Beijing, and when it started, I found I couldn’t understand any of the dialogue. All the words were spoken in the wrong tone, with the wrong stress, and yet they had a maddening similarity to Mandarin that made comprehensibility seem just out of reach. It was as though I’d had a stroke, and a portion of my mind’s speech center had been injured.