A Scientific Study of Extreme Changes in Human Behavior, Psychology, Behavioral Finance, and Human Nature This book was written to answer one deceptively simple question: what, precisely, did COVID-19 change in us? Not in our economies or hospitals alone, but in the wiring of our attention, the architecture of our trust, the math we do when we decide whether to spend or save, and the quiet arithmetic by which we decide who counts as "us" and who does not.