We consider ourselves rational, modern people. Yet, we wear "lucky socks" to job interviews, avoid the number 13, and say "bless you" when someone sneezes. Anthropologist Sarah Jennings explores the persistence of irrational beliefs in "Knock on Wood."Jennings argues that superstition is not a sign of ignorance, but a psychological coping mechanism for uncertainty. When we lack control over an outcome (like in sports, gambling, or war), the brain creates rituals to impose order on chaos. The book draws on Skinner's pigeon experiments and modern neuroscience to explain "magical thinking"-the...