In this text, Robert Kaplan explores the peculiar course that the notion of nothing or its mathematical representative, zero, has taken throughout history. Forced into our awareness 4000 years ago by the need to count ever larger multitudes, zero drifted in and out of focus, disappeared for centuries, then swept from the East into the medieval world, with fears and superstitions crouched around it. Did we discover or invent it? Was it the devil's work? Is it a number or a fiction? Its users came to see that it held immense power to unriddle the universe, leading to profound insights into the mind and the world. And now new layers are coming to light: our computers speak only in zeros and ones, and, for a cosmologist, zero alone can be made to generate everything.