A flap of wings in Beijing

In 1972, the meteorologist Edward Lorenz delivered a paper at the American Association for the Advancement of Science under a title that has long outlived the talk: “Predictability: Does the Flap of a Butterfly’s Wings in Brazil Set Off a Tornado in Texas?” Lorenz had earlier used a seagull. The butterfly stuck. Small perturbations, in a sufficiently complex system, produce disproportionate consequences. It was a useful image for atmospheric science. It was an irresistible one for venture capital. Manus (the artificial intelligence start-up that became China’s most-discussed AI product of 2025 after DeepSeek) was a subsidiary of a parent firm…