The Demon-Haunted World: Science as a Candle in the Dark

by Carl Sagan

When I was a boy, our house was filled with monsters. They lived in the closets, under the beds, in the attic, in the basement, and—when it was dark—just about everywhere. This book is dedicated to my father, who kept me safe from all of them. Maybe the abduction therapists should be doing more of that. Part of the reason that children are afraid of the dark may be that, in our entire evolutionary history up until just a moment ago, they never slept alone. Instead, they nestled safely, protected by an adult—usually Mom. In the enlightened West we stick them alone in a dark room, say goodnight, and have difficulty understanding why they’re sometimes upset. It makes good evolutionary sense for children to have fantasies of scary monsters. In a world stalked by lions and hyenas, such fantasies help prevent defenseless toddlers from wandering too far from their guardians. How can this safety machinery be effective for a vigorous, curious young animal unless it delivers industrial-strength terror? Those who are not afraid of monsters tend not to leave descendants. Eventually, I imagine, over the course of human evolution, almost all children become afraid of monsters. But if we’re capable of conjuring up terrifying monsters in childhood, why shouldn’t some of us, at least on occasion, be able to fantasize something similar, something truly horrifying, a shared delusion, as adults?