Even in our age of infinite distraction, life can be oppressively dull. Many scholars argue that boredom is an invention of 18th-century intellectuals who found themselves with overabundant leisure time. A surprising amount of subsequent art, philosophy, and theological writing channels their feelings of existential melancholy. Toohey, however, demonstrates that boredom’s roots are primal—a visceral and useful adaptation that steers us from toxic social situations. So let yourself get bored. It’s good for you.